HU209327B - Process for more intensive pirometallurgic refining primere copper materials and copper-wastes containing pb and sn in basic-lined furnace with utilizing impurity-oriented less-corrosive, morestaged iron-oxide-based slag - Google Patents

Description

The present invention relates to a slag-forming mixture for the refining of lead and tin-containing primary copper materials and copper scrap in a basic lining furnace.

It is known that refining of copper in copper was initially carried out in an acid-lined flame furnace (Edmund R. Thews, Metallurgical Verification of the Altmetallen und Rüchstand, Bánd II, Cari Hanser Verlag, Munich, 1951). The quartz lining of the furnace was a major contributor to the development of the slurry, a well-managed metallurgical slag. The natural consequence of this was that due to the extremely intense corrosion caused by chemical reactions, the liner was worn out in a relatively short period of time.

With the introduction of basic linings, the working life of furnaces has been extended. The slag used for the process consisted mainly of oxides of contaminants and was extremely viscous, difficult to handle, and occasionally became flaky. The copper oxide and copper content of the slag generally increased to 50-70%, but sometimes reached 80%. Due to the high content of copper oxide, the infiltration capacity of some of the slag elements has increased and this has caused the wear of the basic lining. Eutectic formation as a result of the interaction between the oxide constituents of the chromium-magnesite liner and the copperocide (F. Harders, S. Kienow, Feuerfestkunde; ).

Occasionally, boron trioxide or boron dioxide-containing substances (colemanite, asharite, boric acid) have been used as a slag generator in order to take advantage of the melting point effect of boron trioxide and to increase the slurry fluidity. This did not affect the copper oxide content of the oxide form while reducing the viscosity, but at the same time significantly hastened the wear of the basic lining.

It is therefore an object of the present invention to provide a solution that reduces the rate of liner corrosion and the copper content of the slag compared to conventional solutions, while being cheap.

The present invention is based on the discovery that slag is not an ideal state of equilibrium, but a so-called redox slag, in which the lower and higher oxides of the constituents, such as Cu ₂ O and CuO, FeO, FeOFe ₂ O ₃ , etc., are present. . The individual phases of the slag consist of these oxides and their chemical compounds, which are converted during the refining of copper as a function of oxygen potential and concentration.

The present invention is further based on the discovery that in the refining of primary copper materials and copper waste containing Pb and Sn in a basic-lined furnace, iron contaminated industrial by-product (red sludge), copper-containing industrial by-product (galvanic sludge), calcium and / or kalciumhidroxidból), quartz _(SiO2), and impurity elements removed for refining dip road copper oxides multistage iron oxide (FeO, Feofan ₂ O _3, Fe ₂ O ₃₎ based slag can be formed having the appropriate time and using a quantity of the fireworks the process of refining can be intensified, ie the dose time decreases at the same level of contamination, and the dose time does not increase at higher contamination levels, and as a result, the copper content of the final slag is can be reduced by 50% below.

A further advantage of the slag former used according to the invention is that it is less corrosive and dirt-oriented towards the basic furnace lining, which results in a significant increase in the life of the furnace lining compared to conventional solutions.

Thus, the object of the present invention has been solved with a slag-forming mixture containing 30-70% by weight of red mud,

10 to 30% by weight of calcium oxide, or stoichiometrically equivalent amounts of calcium carbonate and / or calcium hydroxide,

14-30% by weight of silica and

Contains 0-30% by weight of galvanic sludge. The percentages given are by weight, and in the present specification, the percentages are always to be understood as percentages by weight.

The red sludge used in the present invention is the largest byproduct of alumina production, containing predominantly iron oxide, aluminum oxide, silica, and sodium oxide (Technical Lexicon, Academic Publisher, Budapest, 1974, Vol. 3, p. 1055). The electrolysis or electroplating of the galvanic sludge metals also used in the electrolyte bath contains sludge containing metal oxides. It is used in a form free from toxic substances (dangerous anions).

The basic advantage of the present invention is that all the components of the used slag generator are easily accessible and extremely cheap, and even the red and galvanic sludge components are waste which is harmful to the environment and is therefore environmentally beneficial.

Usually calcium oxide is used directly as the calcium carrier, but it is also possible to add an equivalent amount of calcium carbonate or calcium hydroxide (1% calcium oxide corresponds to 1.32% calcium hydroxide or 1.78% calcium carbonate) because these substances are converted to calcium oxide at refining temperature.

The slag obtained according to the invention is a liquid, easy to handle and has a low melting point. The copper content of the finishing slag is only 50% of the copper content of the classical refinery slag, thus increasing the efficiency of the refining of copper.

The basic advantage of the slag generator according to the invention is that the slag produced with the help of it is non-aggressive against the basic furnace lining, by which the lead and tin content of the copper to be refined can be easily and effectively removed.

The slag generator used according to the invention is cheap,

This also makes copper finishing less expensive and less energy consuming.

Further details of the invention will be described by way of exemplary embodiments.

For the technologies described in the examples, red sludge (a) and galvanic sludge (b) were used as follows:

a) Fe (OH) ₃ 54% Al ₂ O ₃ 20% TiO ₂ 5% Sio ₂ 5.1% MgO 0.02% NiO 0.04% PbO 0.02% Na ₂ O 4.5% Moisture: R b) CuO 23% Cao 3% C ₂ O ₃ 6% SiO ₂ 0.6% FeO 10% NiO 1% ZnO 15% A1 ₂ O ₃ 2% Moisture: R Example 1 To test the effectiveness of lead removal,

Injection was performed in a crucible oven, during which 5000 g of 0.32% Pb and 0.17% Sn were refinished. The copper melt to be refined was prepared by combining cathode copper with lead and tin. Decanting was carried out by decantation.

Slag-forming composition:

54.64% red mud 35

16.39% SiO ₂ 28.95% CaO.

30 g of this was added per decant.

After the melting of one third of the insert, a first slag-forming addition was made and air was blown through a copper tube for 5 minutes. Then we scrambled.

Slag addition, air injection, and slagging were similarly done six more times, and in the final step, reduction with CuP ₁₀ alloy was performed and the material was poured.

The chemical composition of the metal is shown in the table below:

Table 1

Operations Cu% Pb% Sn% % Cr 0% P% assimilation after 99.3 0.32 0.17 0,001 0,025 0,001 1. after decantation 99.03 0.15 0.12 0,001 0.49 0,001 2. after decantation 99.00 0.090 0.046 0,001 0.84 0,002 3. after decantation 99.20 0.073 0.019 0,001 0.68 0,001 4. after decantation 98.96 0,030 0,015 0,001 0.87 0,001 5. after decantation 99.21 0,012 0,015 0,001 0.76 0,002 6. after decantation 99.24 0,008 0,015 0,001 0.72 0,003 7. after decantation 99.34 0,003 0,012 0,001 0.63 0,002 After casting 99.83 0,004 0,012 0,001 0.14 0,002

Example 2

In a flame furnace we refined 30,000 kg of copper scrap. The copper scrap was continuously melted and after about 8 t of melting, 300 kg of slag was added to the surface of the molten metal. The composition of the slag generator was as follows:

54.64% red mud 16.39% SiO ₂ and 28.95% CaO.

After the metal bath for approx. Increased to 15 tons, the bath was continuously oxidized through spears introduced through the furnace vault.

After complete oxidation after complete melting, the metal bath was formed and the oxidized copper melt was drained into a reducing furnace, where it was reduced with logs and then poured into anode donna.

During the process, samples were continuously taken from the oxidation furnace and analyzed. Samples were taken at 100 mm bath depth and hourly thereafter. The chemical composition of the samples is shown in Table 2.

Table 2

Chemical composition of the metal:

Sample Cu% Pb% Sn% Fe% Ni% Zn% 0% Ski% ca% First 99.23 0.098 0,048 0,004 0,040 0,013 0.54 0,001 0,001 Second 99.25 0.22 0.15 0.10 0,035 0.12 0.09 0,001 0,001 Third 99.11 0,094 0,013 0,002 0,021 0,001 0.66 0,001 0,001 4th 98.77 0,040 0,020 0.037 0,024 0,010 0.84 0,001 0,006 5th 98.65 0,027 0,018 0,009 0,035 0,004 1.07 0,001 0,003 6th 98.97 0,012 0,017 0,004 0,024 0,002 0.60 0,001 0,005

HU 209 327 Β

Example 3

In a flame furnace we refined 50,000 kg of extremely high impurity copper melt. The copper melt contained 2.2% lead and 2.7% tin.

In the process, after melting 25% of the insert, the following slag former was added in an amount of 2200 kg:

50.72% red mud 18.81% SiO ₂ 27.00% CaO.

3.51% galvanic sludge.

Following the slagging addition, oxidation followed by slagging and pre-oxidation was performed. Slag generator was then added again in an amount of 2.5 t. The slag-forming composition added for the second time was as follows:

54.64% red mud 16.39% SiO ₂

28.95% CaO.

After the second slag addition, oxidation, slagging, reduction and casting were performed again. Copper and iron-containing industrial by-products were used as the deoxidizing agent and CuP10O alloy as the final deoxidizing agent. The slag formation was carried out in the same way as one addition and one removal.

During the process, the molten metal was sampled every 50 minutes until pre-oxidation and every 30 minutes thereafter. Table 3 shows the change in metal composition.

Table 3

Chemical composition of the metal:

Sample Cu% Pb% Sn% % Cr Fe% Ni% Zn% al% S% P% 3.1% O 3.2 95.05 2.13 2.68 0,001 0,005 0,005 0,007 0.0009 0.0038 0,001 0,033 3.3 95.07 2.22 2.57 0,001 0,004 0,006 0,006 0.0021 0.0057 0,001 0.088 3.4 95.33 2.09 2.39 0,001 0,004 0,007 0,008 0.01 .0047 0,002 0,138 3.5 95.65 1.89 2.25 0,002 0,002 0,005 0,004 0.01 0.0046 0,001 0.148 3.6 95.90 1.98 1.86 0,003 0,003 0,007 0,004 0.01 0.0038 0,003 0,166 3.7 97.12 1.44 0.97 0,001 0,003 0,009 0,003 0,007 0.0020 0,002 0.350 by oxidation 3.8 96.43 1.49 0.74 0,001 1.23 0,009 0,013 0,001 0.0080 0,005 3.9 96.33 1.62 0.73 0,001 1.16 0.011 0,017 0,075 .0117 0,006 3:10 97.16 1.43 0.98 0,001 0.30 0,012 0,012 0,001 .0122 0,022 3:11 97.83 1.10 0.90 0,001 0,004 0,010 0,007 0.0008 .0122 0.102 3:12 98.05 0.80 0.92 0,001 0,004 0,010 0,002 0.0007 0.0094 .179 3133 * 98.60 0.47 0.80 0,001 0,006 0,010 0,004 0.0008 .0088 0,000

* probe of deoxidized metal

Example 4

In a flame furnace, 30 t of copper scrap was refined. The copper scrap was continuously melted and after 6 hours of melting, 300 kg of slag was added to the surface of the molten metal. The composition of the slag generator was as follows:

69.5% red mud 10.1% calcium carbonate equivalent to 19.4% silica.

After the volume of the molten pad had increased to 12 tons, the bath was continuously oxidized through spears introduced through the furnace vault. After complete oxidation after complete melting, the metal bath was formed and the oxidized copper melt was transferred to a reducing furnace, where it was reduced by a log and then poured into anode form. During the process, samples were continuously taken from the oxidation furnace every 45 minutes and analyzed. The chemical composition of the metal is shown in Table 4.

Table 4

Chemical composition of the metal:

Sample Cu% Pb% Sn% Fe% Ni% Zn% 0% Ski% ca% First 99.31 0.062 0,022 0,003 0.05 0,005 0.46 0,001 0,001 Second 99.14 0.18 0,095 0,005 0.04 0.23 0,012 0,001 0,002 Third 98.85 0.11 0,072 0,008 0.05 0,001 0.74 0,001 0,002 4th 98.72 0.083 0,064 0,006 0.04 0,002 0.82 0,002 0,001

HU 209 327 B

Sample Cu% Pb% Sn% Fe% Ni% Zn% 0% Ski% ca% 5th 98.86 0,051 0.041 0,005 0.03 0,001 0.95 0,002 0,003 6th 98.75 0.029 0,033 0,004 0.03 0,001 1.05 0,001 0,001 7th 98.87 0,016 0,025 0,004 0.03 0,001 0.87 0,001 0,001 8th 99.19 0,006 0.019 0,004 0.02 0,001 0.65 0,001 0,002

Example 5

In a flame furnace, 30 t of copper scrap was refined. The copper scrap was continuously melted and after 10 t of melting, 300 kg of slag was added to the surface of the molten metal. The composition of the slag generator was as follows:

30.3% red mud 29.7% SiO ₂ calcium hydroxide equivalent to 10.5% calcium oxide

29.5% galvanic sludge.

After the amount of molten pad had increased to 20 tons, the bath was continuously oxidized through spears introduced through the furnace vault.

After complete oxidation after complete melting, the metal bath was formed and the oxidized copper melt was transferred to a reducing furnace, where it was reduced by a log and then poured into anode form. During the process, samples were continuously taken from the oxidizing furnace every 50 minutes and analyzed. The chemical composition of the metal is shown in Table 5.

Table 5

Chemical composition of the metal:

Sample Cu% Pb% Sn% Fe% Ni% Zn% 0% Ski% ca% First 99.34 0,072 0,014 0,005 0,020 0,002 0.42 0,001 0,002 Second 99.25 0.23 0.11 0,009 0.073 0.23 0.16 0,001 0,002 Third 98.78 0.15 0.082 0,007 0,059 0,001 0.59 0,001 0,003 4th 98.63 0.09 0,065 0.023 0.041 0,001 0.93 0,001 0,001 5th 98.61 0.04 0.032 0,010 0,008 0,005 1.03 0,001 0,001 6th 98.85 0.04 0,017 0,005 0,003 0,005 0.88 0,001 0,002 7th 99.25 0,008 0.011 0,007 0,003 0,004 0.61 0,001 0,002

Example 6

In a flame furnace, 30 t of copper scrap was refined. The copper scrap was continuously melted and, after 8 hours of melting, 300 kg of slag was added to the surface of the metal melt. The composition of the slag generator was as follows:

44.1% red mud 14.7% SiO ₂

29.4% calcium oxide 11.7% galvanic sludge.

After the amount of molten pad had increased to 15 tons, the bath was continuously oxidized through spears introduced through the furnace vault.

After complete oxidation after complete melting, the metal bath was formed and the oxidized copper melt was transferred to a reducing furnace, where it was reduced by a log and then poured into anode form. During the process, samples were continuously taken from the oxidizing furnace every 50 minutes and analyzed. The chemical composition of the metal is shown in Table 6.

Table 6

Chemical composition of the metal:

Sample Cu% Pb% Sn% Fe% Ni% Zn% 0% Ski% ca% First 99.46 0,030 0,045 0,010 0.03 0,004 0.35 0,001 0,001 Second 99.14 0.16 0,084 0,005 0.03 0.31 0.22 0,001 0,001 Third 99.11 0.10 0,063 0,005 0.02 0,003 0.63 0,001 0,001 4th 98.85 0,064 0,052 0,007 0,008 0,003 0.81 0,001 0,001 5th 98.78 0,035 0,048 0,004 0,012 0,001 0.87 0,001 0,002 6th 98.75 0,020 0.037 0,004 0,006 0,002 0.96 0,001 0,001 7th 99.17 0,009 0,012 0,003 0,006 0,002 0.72 0,001 0,001 8th 99.23 0,004 0.011 0,002 0,005 0,002 0.68 0,001 0,001

HU 209 327 Β

With the slag forming mixture shown in the examples, the lead content of the copper to be refined can be reduced from less than 0.1% to 0.005-0.01% within 6-9 hours including the melting time. At the same time, the tin content can be significantly reduced. To achieve the same result, the conventional method requires about 14 hours. Of course, the solution is also suitable for refining materials with a lead content greater than 0.1%, however, both the final lead content and the refining time increase. 10

Using the conventional method, the flame liner had to be replaced in 84 batches, whereas after the introduction of the invention, the flame liner had a refinement of 167 batches.

It can be seen from the foregoing that the bar-forming mixture according to the invention greatly increases the efficiency of the copper refining and at the same time reduces the related costs. Of course, the examples presented illustrate only a few variations of the slag-forming mixture of the present invention, and within the scope of the appended claims there are many other options available to those skilled in the art.

Claims (1)

Patent Claim Point Slag-forming mixture for the refining of lead and tin-containing primary copper materials and copper scrap in a basic lining furnace, characterized in that 30-70% by weight of red sludge, 10 to 30% by weight of calcium oxide, or stoichiometrically equivalent amounts of calcium carbonate and / or calcium hydroxide, 14-30% by weight of silica and Contains 0-30% by weight of galvanic sludge.