Apparatus for producing copper with improved CO2 balance

Abstract

The present invention relates to an apparatus for the pyrometallurgical CO2-neutral production of copper from copper-containing starting materials. According to the invention, during the melting and / or reduction process, a hydrogen-containing gas is supplied in an amount such that the steam content in the exhaust gas is within a specific target value range.

Description

[Technical Field]

[0001] The present invention relates to an apparatus for the pyrometallurgical production of high-purity copper from copper-containing starting materials, the apparatus having an improved CO balance and / or for the CO2-neutral production of high-purity copper or high-purity copper products. Furthermore, the present invention relates to a method for producing high-purity copper or high-purity copper products, in particular using the apparatus according to the invention, and to the use of the apparatus according to the invention. [Background technology]

[0002] High purity copper is produced mainly via two routes: on the one hand, through the extraction and further processing of copper ore (primary production), and on the other hand, through the recycling of, for example, copper-containing scrap, end-of-life products or production residues (secondary production).

[0003] In systems known from the prior art, the melting unit is usually operated using fossil fuel burners, using natural gas, oil, etc. as the energy source. The subsequent refining is also carried out by using (injecting) fossil fuel energy sources, e.g., natural gas, into the refining furnaces. When these fossil fuels are burned, large amounts of CO2 are produced, which are eventually released into the atmosphere. This can represent a significant proportion of the overall balance of a production facility. Summary of the Invention

[0004] The present invention is based on the object of providing an apparatus for improving copper production with improved CO2 balance.

[0005] The object underlying the present invention is achieved by a device having the features of claim 1 and a method according to claim 9. Further preferred embodiments are set out in the dependent claims.

[0006] More specifically, the object underlying the present invention is achieved by an apparatus suitable and / or configured for producing copper having a purity of at least 95% from a copper-containing starting material, the apparatus comprising at least one melting unit for producing a liquid first copper-containing intermediate product and at least one conversion unit for producing a second liquid copper-containing intermediate product from the first copper-containing intermediate product. The apparatus further comprises supply means configured to supply an adjustable volumetric flow rate of a hydrogen-containing gas to the melting unit and / or the conversion unit, the hydrogen-containing gas being selected from the group consisting of H2, NH3, H2-inert gas mixtures, or mixtures of H2 or NH3 with CH4. The inert gas may be argon (Ar) or, preferably, nitrogen (N2). According to the present invention, the volumetric flow rate of the hydrogen-containing gas to the melting unit and / or the conversion unit, set by the supply means, is such that the vapor content in the exhaust gas of the melting unit and / or the conversion unit is within a specific target value range. The vapor content may be an absolute vapor content. The vapor content may preferably be a process parameter during the ongoing operation of the relevant unit under consideration.

[0007] In particular, it may be the vapor content occurring in the stationary phase of the process carried out in the unit under consideration.

[0008] The apparatus according to the invention for producing copper can also be called an apparatus for purifying copper, in particular an apparatus for purifying copper from copper-containing starting materials.

[0009] One of the core concepts of the present invention is the use of hydrogen-containing gas to provide the necessary reaction energy, specifically the targeted control of the oxygen partial pressure in the melting unit, especially in the conversion unit where refining takes place. According to the present invention, the supply of hydrogen-containing gas can be adjusted via the steam content in the exhaust gas of the melting unit and / or conversion unit so that the process is as energy-efficient as possible. On the one hand, this reduces or completely prevents the use of conventional fossil fuels. On the other hand, it ensures that the processes in the melting unit and / or conversion unit are carried out with an optimized supply of hydrogen-containing gas. In both cases, this results in an improved CO2 balance.

[0010] It has been found that in order to ensure the most energy-efficient process possible, the specified target value ranges for the steam content in the exhaust gases from the melting unit and / or conversion unit are specific to the relevant unit under consideration.

[0011] The apparatus according to the present invention may be suitable and / or configured to produce copper having a purity of 95% or more, 97% or more, 98.2% or more, or 98.9% or more. Preferably, the produced copper may be in liquid or solid form. The indicated copper percentages may preferably be in weight percent (wt.%). In particular, the first or second intermediate product that can be produced using the apparatus according to the present invention may be in liquid form, i.e., a liquid substance. As described below, if the state of matter does not change during the conversion of the first intermediate product to the second intermediate product, the production process is advantageously further optimized in terms of energy consumption and thus the CO balance is improved. In other words, according to the present invention, the first copper-containing intermediate product can be converted into the second copper-containing intermediate product by the apparatus without changing the state of matter, in particular the liquid state of the substance.

[0012] The copper-containing starting material can be any suitable copper-containing material. In particular, the copper-containing starting material can be a solid-state material. Furthermore, the copper-containing starting material can be or contain copper concentrate and / or copper scrap. The copper concentrate can have a copper content of 10% to 40%, preferably 15% to 35%. The copper concentrate can be so-called "low-grade," "medium-grade," or "high-grade" copper scrap, particularly scrap according to the WEEE Directive (EU Directive 2012 / 19 / EU). The copper-containing starting material can have a copper content within the range of 10% to 99%, 35% to 99%, or 81% to 98%.

[0013] The apparatus according to the invention comprises at least one melting unit, which may be suitable and / or configured to produce a liquid first copper-containing intermediate product, or which may be suitable and / or configured to produce a liquid first copper-containing intermediate product from a solid copper-containing starting material.

[0014] The melting unit may be any suitable melting unit known to those skilled in the art. In particular, the melting unit may be suitable and / or configured to melt or liquefy a solid copper-containing starting material. The melting unit has an internal space capable of accommodating the copper-containing starting material or the first copper-containing intermediate product. The melting unit may also be suitable and / or configured to separate the first liquid copper-containing intermediate product from undesired materials, e.g., in the form of a slag, from the copper-containing starting material. The melting unit may also be suitable and / or configured to oxidize some accompanying elements contained in the copper-containing starting material, in particular S, C, Al, Zn, Pb, Sn, Ni, Co, As, and / or Fe, which separate from the melt via the slag or gas phase. For this purpose, the melting unit may have a supply means for an oxygen-containing gas. The melting unit may also be suitable and / or configured to perform pyrometallurgical extraction of copper from the copper-containing starting material, in particular two-stage pyrometallurgical extraction.

[0015] The melting unit may in particular be selected from the group consisting of bath melters, arc furnaces, in particular EAF (electric arc furnaces) or SAF (submerged arc furnaces), induction furnaces, TBRC (top-blown rotary converters) (also called culdo converters), TRF (tilt furnaces), ETRF (elliptical tilt furnaces) and ladle furnaces.

[0016] The bath melting apparatus may have a gas burner as a supply means, and may further have an upper lance for supplying oxygen and / or hydrogen-containing gas. The bath melting apparatus may further include a laterally disposed nozzle for introducing oxygen and / or hydrogen-containing gas into the interior space of the bath melting apparatus.

[0017] The EAF or SAF may have as heating device a heating device for generating an (open) arc furnace. Furthermore, the EAF or SAF may have as supply means a gas burner.

[0018] The induction furnace may comprise an induction heater, in particular an induction coil arranged around the crucible.

[0019] The TBRC may have a gas burner and additionally a top lance as supply means for supplying oxygen-containing gas and / or hydrogen-containing gas.

[0020] The TRF or ETRF may have a gas burner, particularly a front wall burner, as a supply means. Furthermore, one or more nozzles may be present to introduce oxygen- and / or hydrogen-containing gas into the interior space of the TRF or ETRF. These nozzles of the TRF or ETRF may be designed to be able to rotate under the bath.

[0021] The ladle furnace may have a gas burner and / or an electrically operated heating device as a supply means, and furthermore, the ladle furnace may have an upper lance as a supply means for supplying oxygen and / or hydrogen-containing gas.

[0022] The first copper-containing intermediate product may have a copper content of 70% or more, preferably 75% or more and 99.8% or less, preferably 99.5% or less, and may further have an oxygen content of 6000 ppm or less, preferably 4000 ppm or less.

[0023] The first copper-containing intermediate product may have a temperature of 1100°C or higher and 1400°C or lower, preferably 1150°C or higher and 1350°C or lower. This temperature may be present, particularly when the first copper-containing intermediate product has the copper content described above. This copper content of the first copper-containing intermediate product may also be referred to as the target copper content of the first copper-containing intermediate product. This temperature may also be present before the first copper-containing intermediate product is transferred to the conversion unit and / or when the first copper-containing intermediate product exits the melting unit.

[0024] The apparatus according to the present invention comprises at least one conversion unit suitable and / or configured to produce a second copper-containing intermediate product in liquid form from a first liquid copper-containing intermediate product, the conversion unit having an internal space capable of accommodating the first copper-containing intermediate product or the second copper-containing intermediate product.

[0025] The conversion unit may be any suitable conversion unit known to those skilled in the art. The conversion unit may also be referred to as a purification unit, particularly a pyrolysis purification unit. In particular, the conversion unit may be suitable and / or configured to reduce and / or oxidize a liquid first copper-containing intermediate product to produce a second liquid copper-containing intermediate product. Preferably, the conversion unit is suitable and / or configured to at least reduce the liquid first copper-containing intermediate product. Also preferably, the conversion unit is suitable and / or configured to first oxidize and then reduce the liquid first copper-containing intermediate product.

[0026] The conversion unit may be suitable and / or configured to increase the oxygen partial pressure in the first liquid copper-containing intermediate product, thereby oxidizing the liquid copper-containing intermediate product. This can be achieved, for example, by supplying an oxygen carrier, such as air and / or O2. For this purpose, the conversion unit may have a supply means for the oxygen carrier. Increasing the oxygen partial pressure in the first liquid copper-containing intermediate product can oxidize and thereby slag its further components, particularly Pb, Sn, Ni, Sb, Zn, Ni, Co, As, and Fe, leading to further purification. Although these components have a substantially higher affinity for oxygen than copper, copper is also oxidized.

[0027] The conversion unit may additionally or alternatively be suitable and / or configured to reduce the oxygen partial pressure in the first liquid copper-containing intermediate product, thereby allowing the reduction of the liquid first copper-containing intermediate product.

[0028] This can be achieved according to the invention by supplying a hydrogen-containing gas selected from the group consisting of H2, NH3, or a mixture of H2, CH4, and / or NH3. For this purpose, the conversion unit can have a supply means for the hydrogen-containing gas.

[0029] The converter unit may in particular be selected from the group consisting of a DSC (Peirce-Smith converter), a ladle furnace, an anode furnace, a TBRC, a TRF, and an ETRF.

[0030] The PSC may include a gas burner, particularly a front wall burner. Additionally, one or more nozzles may be present to introduce oxygen- and / or hydrogen-containing gases into the interior space of the PSC. These nozzles of the PSC may be designed to be able to rotate under the bath.

[0031] The anode furnace may have gas burners, in particular front wall burners. Furthermore, one or more nozzles may be present for introducing oxygen- and / or hydrogen-containing gases into the interior space of the anode furnace. These nozzles of the anode furnace may be designed to be rotatable under the bath.

[0032] The melting unit and the conversion unit can be the same unit. This is particularly the case for TBRC, TRF, ETRF, and ladle furnaces. This achieves several advantages. In particular, no movement of the first copper-containing intermediate is required, which saves energy to counteract the cooling of the first copper-containing intermediate product.

[0033] The apparatus according to the invention may be suitable and / or configured to provide the second liquid copper-containing intermediate product without changing the first copper-containing intermediate product from a liquid state of matter to a solid state of matter, in other words, the apparatus may be suitable and / or configured to carry out the transfer of the first copper-containing intermediate product from the melting unit to the converting unit, wherein the first copper-containing intermediate product retains its liquid state of matter.

[0034] The apparatus may be suitable and / or configured to maintain the temperature of the liquid first copper-containing intermediate product above its melting point. This can be achieved by ensuring that the melting unit and the conversion unit are the same unit, as described above. Alternatively, the apparatus may include a transfer means for transferring the liquid first copper-containing intermediate product from the melting unit to the conversion unit. The transfer means may comprise a heating device, such as an electrically operated heater and / or a gas burner. Alternatively or additionally, the transfer means may be insulated, for example by a cover. The transfer means may be constituted, for example, by a channel and / or a ladle.

[0035] The melting unit and / or the converting unit may have at least one heating device, in particular at least one additional heating device. An "additional" heating device means that an additional heating device is present in addition to the heating device already included as standard in the melting unit and / or the converting unit. For example, an induction furnace has an induction heater, e.g., an induction coil arranged around the crucible, or an arc furnace always has an arc heater. According to the present invention, the unit may have at least one further heating device in addition to this known heating device.

[0036] Preferably, the heating device, in particular the additional heating device, may be an electrically operated heating device and / or a burner, in particular a gas burner.

[0037] If the heating device or the additional heating device comprises a gas burner, this may be identical to the supply means according to the invention for supplying hydrogen-containing gas to the melting unit and / or the conversion unit, or may be different therefrom, i.e. formed by an independent assembly.

[0038] The electrically operated heating device can preferably be operated with electrical energy from renewable sources. Conversely, the device according to the invention can be suitable and / or configured to operate the electrically operated heating device using electrical energy from renewable sources. This advantageously achieves a further improved CO2 balance. The term "electrical energy from renewable sources" can be used to describe CO2-neutral supplied electrical energy and / or "green power". Electrical energy from renewable sources can include, for example, electrical energy from hydroelectric power, biomass, biogas, geothermal energy, wind power, and / or solar power.

[0039] The electrically operated heating device may be selected from the group consisting of an electrically operated radiant heater, an electrically operated convection heater, a resistance heater, an induction heater, an arc heater, and combinations thereof. Preferably, the heating device may be designed as an induction heater and / or an arc heater, and even more preferably, the heating device may be designed as an induction heater.

[0040] The gas burner may preferably be operated using hydrogen-containing gas produced from a renewable source. Conversely, the apparatus may be suitable and / or configured to operate the gas burner using hydrogen-containing gas produced from a renewable source.

[0041] This also advantageously results in a further improved CO balance being achieved. The term "hydrogen-containing gas produced from renewable sources" can be used to describe hydrogen-containing gas that is supplied CO2-neutral and / or "green gas". An example of this is hydrogen produced by splitting water using an electrolyzer, where the energy required for electrolysis was fully covered by renewable energy such as wind energy, geothermal energy, or solar energy.

[0042] In the case of an induction furnace or an arc furnace, the heating device of the melting unit may preferably be an additional non-electrically operated heating device, in particular a gas burner. In this case, the melting unit has at least one electric heating device and at least one non-electric heating device, in particular a gas burner. In the case of a bath melting device, a TBRC, a TRF, or an ETRF, the heating device of the melting unit may preferably be an additional electrically operated heating device, in particular an induction heater. In this case, the melting unit has at least one non-electric heating device and at least one electric heating device, in particular an induction heater.

[0043] The heating device of the conversion unit may also be an additional electrically operated heating device, in particular an induction heater, in which case the conversion unit comprises at least one non-electrical heating device, in particular a gas burner, and at least one electric heating device.

[0044] The second copper-containing intermediate product may have a copper content in the range of 95.0% to 99.9%, preferably 98.0% to 99.9%, or 98.2% to 99.8%. The second copper-containing intermediate product may have an oxygen content of 2500 ppm or less, preferably 2000 ppm or less.

[0045] The supply means according to the invention can be any suitable supply means known to those skilled in the art, capable of supplying or injecting a hydrogen-containing gas into the melting unit and / or the conversion unit. The supply means (for both hydrogen and oxygen-containing gas) can, for example, be designed as a burner, in particular a gas burner and / or a front burner, or can be in the form of a gas lance or injector. The supply means can include a valve, a proportional valve, or a process controller.

[0046] The supply means may open into the interior space of the melting unit and / or the conversion unit (receiving the first or second copper-containing intermediate product) and / or may be at least partially or completely located therein, thereby ensuring that a hydrogen-containing gas can be introduced into the melting unit and / or the conversion unit. The supply means may further be fluidly connected to at least one reservoir for the hydrogen-containing gas. In particular, if the hydrogen-containing gas is a gas mixture, several reservoirs with different hydrogen-containing gases may be fluidly connected to the supply means. At least one mixing means for adjusting the gas mixture may be located between the reservoir and the supply means. This / these reservoirs and / or mixing means may be components of the device according to the invention.

[0047] The supply means may comprise a nozzle, in particular a refining nozzle. The supply means may also be selected from the group consisting of a nozzle, in particular a refining nozzle, a gas burner, a lance, in particular a gas lance, a purging stone, and an impeller.

[0048] Preferably, the hydrogen-containing gas can be a gas mixture, particularly an H2-inert gas mixture, or more preferably a gas mixture of H2 or NH3 with CH4. Here, a gas mixture of H2 and CH4 is particularly preferred. Advantageously, the CO2 balance improves with increasing substitution of H2 and / or NH3 as the energy source, which means that carbon-containing energy sources such as CH4 can be omitted. This is particularly true when H2 and / or NH3 are gases produced in a "green" manner. It is also preferred that the hydrogen-containing gas is carbon-free. These gas mixtures, particularly gas mixtures consisting of H2 and CH4, can have an H2 proportion (volume percent) in the range of 10% to 80%, more preferably 25% to 70%, 25% to 50%, and even more preferably 25% to 35%. These gas mixtures, in particular those consisting of NH3 and CH4, can have an NH3 proportion (volume percent) in the range of 10% to 80%, more preferably 25% to 70%, 25% to 50%, and even more preferably 25% to 35%. These proportions of H2 or NH3 have proven particularly advantageous and therefore suitable for the apparatus according to the invention for producing copper with an improved CO2 balance.

[0049] The gas mixture of H2 or NH3 with CH4 or the H2-inert gas mixture may be a gas mixture containing or consisting of the above-mentioned components.

[0050] The supply means may be a controllable supply means, and the apparatus may be configured to determine the steam content in the exhaust gas of the melting unit and / or the conversion unit and control the supply means in response to the determined steam content. The term "controllable" means that the amount of hydrogen-containing gas supplied to the melting unit and / or the conversion unit is variable over time during operation of the apparatus according to the present invention. In other words, the volumetric flow rate of hydrogen-containing gas to the unit and / or the partial pressure of hydrogen-containing gas in the first or second liquid copper-containing intermediate product can be changed during operation of the apparatus. Such control of the gas flow introduced into the melting unit and / or the conversion unit can be achieved, for example, via a controllable valve or a process controller.

[0051] The device according to the present invention may further be configured to determine the steam content in the exhaust gas of the melting unit and / or the conversion unit. For this purpose, the device may have at least one means for determining the steam content in the exhaust gas of the melting unit and / or the conversion unit. The measurement of the steam content in the exhaust gas may preferably be performed using an FTIR spectrometer. Alternatively or additionally, the steam content may be determined by measuring the oxygen content, hydrogen content, and / or temperature in the exhaust gas. The device according to the present invention and / or the means for determining the steam content may have at least one sensor selected from the group consisting of an oxygen sensor, a hydrogen sensor, a temperature sensor, or a combination thereof.

[0052] The at least one sensor can be arranged at least partly or completely in the exhaust gas volume flow of the melting unit and / or the conversion unit.

[0053] A suitable sensor for determining the steam content and / or O2 content in the exhaust gas may be an FTIR spectrometer. A suitable sensor / probe for measuring temperature may be a thermocouple, for example a PT100 thermocouple, in particular type K, type S, or type B.

[0054] The regulation and / or control of the supply means can be performed via a calculation unit, which can be a component of the device according to the invention. The calculation unit can be configured to regulate and / or control the supply means. The calculation unit can further be connected to means for determining the vapor content, in particular at least one or all of an FTIR spectrometer, an oxygen sensor, a hydrogen sensor, a temperature sensor, and combinations thereof. The calculation unit can further be configured to determine the vapor content in the exhaust gas from the sensor measurements, in particular from the measured oxygen content, hydrogen content, and / or temperature.

[0055] As previously mentioned, the specified target ranges for the steam content in the exhaust gas from the melting unit and / or the converting unit are specific to the unit under consideration. These target ranges, and preferred target ranges, are disclosed below.

[0056] The target value of the steam content in the exhaust gas of the melting unit during melting can be in the range of 0% to 99%, 20% to 99%, 50% to 99%, 0% to 51%, or more than 0% to 5%.

[0057] In the case of a bath melting apparatus as the melting unit, the target value of the steam content in the off-gas during melting can be in the range of 15% to 80%, preferably 15% to 45%, or, in the case of a bath melting apparatus, particularly with a supersonic injector for hydrogen-containing gas, the target value during melting can be in the range of 40% to 99%, preferably 80% to 99%.

[0058] In the case of an electric arc furnace as melting unit, in particular an SAF, the target value for the steam content during melting can be in the range of 0% to 10%, preferably 0% to 5%.

[0059] In the case of an induction furnace as melting unit, the target value for the steam content in the off-gas during melting can be in the range of 0% to 10%, preferably 0% to 5%.

[0060] In the case of a TBRC as a melting unit, the target value of the steam content in the off-gas during melting may be in the range of 40% to 99%, preferably 80% to 99%.

[0061] In the case of a TRF or ETRF as the melting unit, the target value of the steam content in the off-gas during melting may be in the range of 20% to 99%, preferably 50% to 99%.

[0062] In the case of a ladle furnace as the melting unit, the target value of the steam content in the off-gas during melting can be in the range of 40% to 99%, preferably 80% to 99%.

[0063] The target value of the steam content in the exhaust gas of the conversion unit during reduction may be in the range of 15% to 99%, preferably 15% to 45%.

[0064] In the case of a PSC as the conversion unit, the target value of the steam content in the exhaust gas during reduction can be in the range of 20% to 99%, preferably 50% to 99%. If a PSC is used to oxidize the first copper-containing intermediate product before reduction, the target value of the steam content during oxidation can be in the range of 0% to 25%, preferably 0% to 15%.

[0065] In the case of a ladle furnace as the conversion unit, the target value of the steam content in the off-gas during reduction can be in the range of 15% to 45%, preferably 15% to 35%. When a ladle furnace is used to oxidize the first copper-containing intermediate product before reduction, the target value of the steam content during oxidation can be in the range of 0% to 25%, preferably 0% to 15%.

[0066] In the case of an anode furnace as the conversion unit, the target value of the steam content in the exhaust gas during reduction can be in the range of 15% to 45%, preferably 15% to 35%. In the case of an anode furnace used to oxidize the first copper-containing intermediate product before reduction, the target value of the steam content in the exhaust gas during oxidation can be in the range of 0% to 10%, preferably 0% to 5%.

[0067] In the case of a TBRC as the conversion unit, the target value of the steam content in the exhaust gas during reduction may be in the range of 15% to 45%, preferably 15% to 35%. When a TBRC is used to oxidize the first copper-containing intermediate product before reduction, the target value of the steam content in the exhaust gas during oxidation may be in the range of 0% to 15%, preferably 0% to 10%.

[0068] In the case of a TRF or ETRF as the conversion unit, the target value of the steam content in the exhaust gas during reduction can be in the range of 15% to 45%, preferably 15% to 35%. In the case of a TRF or ETRF used to oxidize the first copper-containing intermediate product prior to reduction, the target value of the steam content in the exhaust gas during oxidation can be in the range of 0% to 25%, preferably 0% to 15%.

[0069] The apparatus according to the present invention may further include an anode casting wheel or granulation means for converting the second copper-containing intermediate product into a third copper-containing intermediate product. The third copper-containing intermediate product may have a solid state material. The third copper-containing intermediate product may be copper granules or copper anodes, each having a copper content of 95% or more. The anode casting wheel may have insulation and / or a heating device, particularly a gas burner, preferably a hydrogen burner.

[0070] The apparatus may include a transfer means for transferring the liquid second copper-containing intermediate product from the conversion unit to the anode casting wheel or granulator. The transfer means may include a heating device, such as an electrically operated heater and / or a gas burner, particularly a hydrogen burner. Alternatively or additionally, the transfer means may be insulated, for example, by a cover. The transfer means may be constituted, for example, by a channel and / or a ladle.

[0071] The apparatus can include a refinement electrolysis unit, particularly a copper anode, for the electrolytic conversion of the copper-containing intermediate product. The electrical energy required for the refinement electrolysis can be obtained from a renewable source. After the refinement electrolysis, the copper-containing product, particularly the copper cathode, can have a copper content of 99.9% or more, preferably 99.99% or more.

[0072] The apparatus may include a unit for leaching and / or hydrometallurgical treatment and a recovery electrolysis unit for electrolytic conversion of the copper-containing intermediate product, in particular copper particulates. The leaching and / or hydrometallurgical conversion unit may have a supply of hydrogen-containing gas, in particular hydrogen. The hydrogen-containing gas may be produced from a renewable source. The electrical energy required to perform the recovery electrolysis may be obtained from a renewable source. After recovery electrolysis, the copper-containing product, in particular the copper cathode, may have a copper content of 99.9% or more, preferably 99.99% or more.

[0073] In the following, some particularly preferred combinations of melting units and converting units are disclosed.

[0074] Preferably, the apparatus according to the present invention may comprise an induction furnace as a melting unit and a TRF or ETRF as a conversion unit. The volumetric flow rate of hydrogen-containing gas to the induction furnace is set by the supply means such that the steam content in the induction furnace off-gas when melting the copper-containing starting material is within a specific target value range of 0% to 10%, preferably 0% to 5%. The volumetric flow rate of hydrogen-containing gas to the TRF or ETRF is adjusted by the supply means such that the steam content in the TRF or ETRF off-gas when reducing the first copper-containing intermediate product is within a specific target value range of 15% to 45%, preferably 15% to 35%. When a TRF or ETRF is used in addition to oxidizing the first copper-containing intermediate product before reduction, the target value of the steam content during oxidation may be within a range of 0% to 25%, preferably 0% to 15%.

[0075] Preferably, the apparatus according to the present invention comprises an induction furnace as a melting unit and a ladle furnace as a conversion unit. The volumetric flow rate of hydrogen-containing gas to the induction furnace is set by the supply means such that the steam content in the induction furnace off-gas during melting of the copper-containing starting material is within a specified target value range of 0% to 10%, preferably 0% to 5%. The volumetric flow rate of hydrogen-containing gas to the ladle furnace is adjusted by the supply means such that the steam content in the ladle furnace off-gas during reduction of the first copper-containing intermediate product is within a specified target value range of 15% to 45%, preferably 15% to 35%. If a ladle furnace is used in addition to oxidizing the first copper-containing intermediate product before reduction, the target value of the steam content during oxidation may be within a range of 0% to 25%, preferably 0% to 15%.

[0076] Preferably, the apparatus according to the present invention can have a TRF as both the melting unit and the converting unit. The volumetric flow rate of the hydrogen-containing gas to the TRF, set by the supply means, is such that the steam content in the TRF off-gas during melting of the copper-containing starting material is within a specific target value range of 20% to 99%, preferably 50% to 99%. The volumetric flow rate of the hydrogen-containing gas to the TRF, adjusted by the supply means, is such that the steam content in the ladle furnace off-gas during reduction of the first copper-containing intermediate product is within a specific target value range of 15% to 45%, preferably 15% to 35%. If a TRF is used in addition to oxidizing the first copper-containing intermediate product before reduction, the target value of the steam content during oxidation may be within a range of 0% to 25%, preferably 0% to 15%.

[0077] Preferably, the apparatus according to the present invention can include an ETRF as both the melting unit and the converting unit. The volumetric flow rate of hydrogen-containing gas to the ETRF, set by the supply means, is such that the steam content in the ETRF off-gas during melting of the copper-containing starting material is within a specific target value range of 20% to 99%, preferably 50% to 99%. The volumetric flow rate of hydrogen-containing gas to the ETRF, adjusted by the supply means, is such that the steam content in the ladle furnace off-gas during reduction of the first copper-containing intermediate product is within a specific target value range of 15% to 45%, preferably 15% to 35%. If an ETRF is used in addition to oxidizing the first copper-containing intermediate product before reduction, the target value of the steam content during oxidation can be within a range of 0% to 25%, preferably 0% to 15%.

[0078] Preferably, the apparatus according to the present invention comprises a bath melter as the melting unit and a TBRC as the conversion unit. The volumetric flow rate of hydrogen-containing gas to the bath melter, set by the supply means, is such that the steam content in the off-gas from the bath melter during melting of the copper-containing starting material is within a specified target value range of 15% to 80%, preferably 15% to 45%. If the bath melter has an ultrasonic injector, the target value range is 40% to 99%, preferably 80% to 99%. The volumetric flow rate of hydrogen-containing gas to the TBRC, adjusted by the supply means, is such that the steam content in the off-gas from the ladle furnace during reduction of the first copper-containing intermediate product is within a specified target value range of 15% to 45%, preferably 15% to 35%. If a TBRC is used in addition to oxidizing the first copper-containing intermediate product before reduction, the target value of the steam content during oxidation may be within a range of 0% to 15%, preferably 0% to 10%.

[0079] Preferably, the apparatus according to the present invention comprises an arc furnace, in particular an EAF or SAF, as the melting unit, and a TRF or ETRF as the conversion unit. The volumetric flow rate of hydrogen-containing gas to the arc furnace, set by the supply means, is such that the steam content in the arc furnace off-gas during melting of the copper-containing starting material is within a specific target value range of 0% to 10%, preferably 0% to 5%. The volumetric flow rate of hydrogen-containing gas to the TRF or ETRF, adjusted by the supply means, is such that the steam content in the TRF or ETRF off-gas during reduction of the first copper-containing intermediate product is within a specific target value range of 15% to 45%, preferably 15% to 35%. If a TRF or ETRF is used in addition to oxidizing the first copper-containing intermediate product before reduction, the target value of the steam content during oxidation may be within a range of 0% to 25%, preferably 0% to 15%.

[0080] Preferably, the apparatus according to the present invention may comprise a bath melter as the melting unit and a TRF or ETRF as the conversion unit. The volumetric flow rate of hydrogen-containing gas to the bath melter, set by the supply means, is such that the steam content in the exhaust gas from the bath melter when melting the copper-containing starting material is within a specified target value range of 15% to 80%, preferably 15% to 45%. If the bath melter has an ultrasonic injector, the target value range is 40% to 99%, preferably 80% to 99%. The volumetric flow rate of hydrogen-containing gas to the TRF or ETRF, adjusted by the supply means, is such that the steam content in the exhaust gas from the TRF or ETRF when reducing the first copper-containing intermediate product is within a specified target value range of 15% to 45%, preferably 15% to 35%. If a TRF or ETRF is used in addition to oxidizing the first copper-containing intermediate product before reduction, the target value of the steam content during oxidation may be within a range of 0% to 25%, preferably 0% to 15%.

[0081] Preferably, the apparatus according to the present invention comprises an arc furnace, in particular an EAF or SAF, as the melting unit and an anode furnace as the conversion unit. The volumetric flow rate of hydrogen-containing gas to the arc furnace, set by the supply means, is such that the steam content in the arc furnace off-gas during melting of the copper-containing starting material is within a specific target value range of 0% to 10%, preferably 0% to 5%. The volumetric flow rate of hydrogen-containing gas to the anode furnace, adjusted by the supply means, is such that the steam content in the anode furnace off-gas during reduction of the first copper-containing intermediate product is within a specified target value range of 15% to 45%, preferably 15% to 35%. If the anode furnace is used in addition to oxidizing the first copper-containing intermediate product before reduction, the target value of the steam content during oxidation can be within a range of 0% to 10%, preferably 0% to 5%.

[0082] The second liquid copper-containing intermediate product can be transferred to at least one further unit for further processing into a third copper-containing intermediate product, which is a solid material. Such a unit can preferably be an anode casting wheel or a granulator. The anode casting wheel can have a heating device designed as an electric heater or a gas burner. The heating device can preferably be powered by green gas or green electricity.

[0083] A refinery electrolysis facility can be connected to the anode casting wheel, which can also preferably be powered by green electricity.

[0084] The object underlying the present invention is also achieved by the method according to the present invention and the use according to the present invention of the device according to the present invention, which are described below. To avoid repetition, only the important aspects of the present invention are explicitly stated again. The described features of the device according to the present invention apply equally to the method or the use, and vice versa.

[0085] The method according to the invention for producing copper or copper products with a purity of at least 95% comprises the following method steps: a) providing a copper-containing starting material; b) melting a copper-containing starting material in a melting unit to produce a first liquid copper-containing intermediate product having a copper content of 70% or more; c) reducing the first copper-containing intermediate product in a conversion unit to produce a second copper-containing intermediate product having a copper content of 95% or greater.

[0086] The method according to the invention is further characterized in that during melting and / or reduction, a hydrogen-containing gas is supplied to the melting unit and / or the conversion unit, so that the steam content in the off-gas of the melting unit and / or the conversion unit is within a certain target value range. The hydrogen-containing gas is selected from the group consisting of H2, NH3, H2-inert gas mixtures, or mixtures of H2 or NH3 with CH4.

[0087] The method according to the invention can preferably be carried out using the device according to the invention.

[0088] According to the invention, the copper-containing starting material is melted in a melting unit after its provision in step a) and is converted into a first liquid copper-containing intermediate product.

[0089] The first liquid copper-containing intermediate product is then converted to a second liquid copper-containing intermediate product in a conversion unit in step b). Note again that in some embodiments, the melting unit and the conversion unit can be the same unit. During the conversion of the first liquid copper-containing intermediate product to the second liquid copper-containing intermediate product in the conversion unit, at least a reduction of the first liquid copper-containing intermediate product can be performed.

[0090] During the melting and / or reduction of the first copper-containing intermediate product, a hydrogen-containing gas is supplied to the melting unit and / or the conversion unit. As mentioned above, this may be, in particular, at least one hydrogen-containing gas produced from a renewable source. The hydrogen-containing gas is supplied to the melting unit and / or the conversion unit in an amount or volume flow rate such that the steam content in the exhaust gas of the melting unit and / or the conversion unit is within the specified target value range.

[0091] The copper-containing starting material can be at least partially oxidized during melting, i.e., in process step b), by supplying an oxygen-containing gas, in particular O2 and / or air, to the melting unit via the melting unit's supply means, during which, for example, S, C, Al, Zn, Pb, Sn, Ni, Co, As, Co, As, and / or Fe are oxidized in the copper-containing starting material.

[0092] As mentioned above, some of the disclosed conversion units are configured to not only reduce the copper-containing intermediate product but also oxidize it. Such oxidation is preferably carried out before reduction. Thus, the first copper-containing intermediate product can be at least partially oxidized by the conversion unit before reduction, i.e., after process step b) but before process step c). This can also be achieved by supplying an oxygen-containing gas, in particular O2 and / or air, to the conversion unit via the supply means of the conversion unit. During this oxidation, for example, S, C, Al, Zn, Pb, Sn, Ni, Co, As, and / or Fe in the first copper-containing intermediate product are oxidized.

[0093] Process step b) of the process according to the invention, i.e., melting, can be carried out until the oxygen content of the first copper-containing intermediate product is 6000 ppm or less. Alternatively or additionally, process step c) of the process according to the invention, i.e., reduction, can be carried out until the oxygen content of the second copper-containing intermediate product is 2500 ppm or less.

[0094] Also disclosed is a method for producing copper having a purity of at least 95%, comprising reducing a first copper-containing intermediate product in a conversion unit to produce a second copper-containing intermediate product having a copper content of 95% or more, wherein during the reduction, a hydrogen-containing gas selected from the group consisting of H, NH, an H-inert gas mixture, or a mixture of H or NH with CH is supplied to the conversion unit so that the steam content in the exhaust gas of the conversion unit is within a specified target value range.

[0095] Furthermore, the use of an apparatus according to the invention, in particular according to one of the apparatus claims, for producing copper having a purity of at least 95% from a copper-containing starting material is disclosed.

[0096] Further advantages, details and features of the invention can be found in the embodiments described below. [Brief explanation of the drawings]

[0097] [Figure 1] 1 is a schematic diagram of a first embodiment of an apparatus according to the invention having an induction furnace as a melting unit and a TRF or ETRF as a conversion unit; FIG. [Figure 2] FIG. 1 is a schematic diagram of a further embodiment of an apparatus according to the invention having a TRF or ETRF functioning as both a melting unit and a converting unit. DETAILED DESCRIPTION OF THE INVENTION

[0098] In the following description, the same reference numerals represent the same components or features, so that a description of a component with reference to one drawing also applies to other drawings.

[0099] FIG. 1 is a schematic diagram of a first embodiment of a device 1 according to the invention.

[0100] The apparatus 1 comprises a melting unit 3 in the form of an induction furnace and a conversion unit 4 in the form of a tilted refining furnace (TRF). In an alternative embodiment, an elliptical tilted refining furnace (ETRF) can be used instead of the TRF.

[0101] Within the interior space of induction furnace 3 can be found a first liquid copper-containing intermediate product 5 produced from copper-containing starting material 2 in the solid state of matter. The interior space of TRF 4 contains a second liquid copper-containing intermediate product 6 produced by oxidation and reduction of first copper-containing intermediate product 5.

[0102] The induction furnace 3 is connected to the TRF 4 by a transfer means 7 in the form of an insulated channel. This ensures that the first liquid copper-containing intermediate product 5 can be transferred from the melting unit 3 to the conversion unit 4 without changing its (liquid) state of matter. The device 1 according to the invention can have a further transfer means 12, which can also be designed in the form of a channel or ladle. This further transfer means 12 serves to transfer the second liquid copper-containing intermediate product 5 from the conversion unit 4, i.e. the TRF, to at least one additional unit, for example an anode casting wheel, for further processing of the copper-containing intermediate product.

[0103] The first copper-containing intermediate product has a copper content in the range of 75% to 99.5%. The second copper-containing intermediate product has a copper content in the range of 98.2% to 99.8%.

[0104] The induction furnace 3 has an electric heating unit in the form of an induction heater formed by an induction coil arranged around the crucible. The energy supply of the electric heating unit of the induction furnace 3 is provided by a power supply 11 providing electric energy from a renewable source.

[0105] The induction furnace 3 further comprises a supply means (not shown) with a gas lance for supplying an adjustable volumetric flow of a hydrogen-containing gas mixture to the induction furnace. Preferably, the supply means is designed to be controllable and is controlled depending on the steam content in the exhaust gas of the induction furnace. The volumetric flow of the hydrogen-containing gas mixture through the supply means is adjusted, in particular controlled, during the steady state phase of the melting operation so that the steam content in the exhaust gas of the induction furnace is not more than 10%, preferably not more than 5%.

[0106] The supply means of the induction furnace 3 is connected to a storage or supply connection 9 for a hydrogen-containing gas mixture. The gas mixture is a mixture of CH4 and H2 in a percentage ratio of 65:35, which is also used in the conversion unit 4.

[0107] The TRF 4 also has a supply means 10 connected to a storage or supply connection 9 for a hydrogen-containing gas mixture, which can introduce the hydrogen-containing gas mixture into the TRF. The supply means 10 is designed here as a gas burner, in particular as a front wall burner. The TRF 4 can further comprise an additional electric heating device, which can also be supplied with energy via a power supply 11. Furthermore, the TRF has supply means in the form of two to eight nozzles 13, through which an oxygen-containing gas, preferably O2 and / or air, can be introduced into the interior space of the TRF 4. For reduction, a hydrogen-containing gas selected from the group consisting of H2, NH3, H2-inert gas mixtures, or mixtures of H2 or NH3 with CH4 can also be introduced through the same nozzles 13.

[0108] Preferably, the supply means 10 and 13 of the TRF are designed to be controllable and are controlled depending on the steam content in the exhaust gas of the TRF. The volumetric flow rate of the hydrogen-containing gas mixture through the supply means is adjusted, preferably controlled, so that in the oxidation operation of the TRF, the steam content in the exhaust gas of the TRF is in the range of more than 0% to less than 25%, preferably in the range of more than 0% to less than 20%. However, in the reduction operation of the TRF following the oxidation operation, the volumetric flow rate is adjusted, preferably controlled, so that the steam content in the exhaust gas of the TRF is in the range of more than 15% to less than 45%, preferably in the range of more than 15% to less than 35%.

[0109] FIG. 2 is a schematic diagram of a further embodiment of the device 1 according to the invention.

[0110] Apparatus 1 has only one TRF that functions as both melting unit 3 and converting unit 4. In an alternative embodiment, it is an ETRF that functions as both melting unit 3 and converting unit 4. The TRF and ETRF correspond to those in FIG. 1 . Thus, copper-containing starting product 2 is first converted to a first liquid copper-containing intermediate product 5 in TRF 4 in its function as melting unit 3. Subsequently, first liquid copper-containing intermediate product 5 is converted to a second liquid copper-containing intermediate product 6 in TRF 4. Therefore, the transfer means shown in FIG. 1 for transferring liquid first copper-containing intermediate product 7 is omitted.

[0111] The TRF 4 has a supply means 10 connected to a storage or supply connection 9 for a hydrogen-containing gas mixture and capable of introducing the hydrogen-containing gas mixture into the TRF. The supply means 10 is designed here as a gas burner, in particular as a front wall burner. The TRF 4 can optionally be equipped with an additional electric heating device, which can also be supplied with energy via a power supply 11. Furthermore, the TRF has supply means in the form of two to eight nozzles 13, through which an oxygen-containing gas, preferably O2 and / or air, can be introduced into the interior space of the TRF 4. For the reduction, a hydrogen-containing gas selected from the group consisting of H2, NH3, H2-inert gas mixtures, or mixtures of H2 or NH3 with CH4 can also be introduced through the same nozzles 13.

[0112] The gas mixture introduced via the supply means may be a mixture of CH4 and H2 in a percentage ratio of 60:40.

[0113] Preferably, the TRF supply means 10 and 13 are designed to be controllable and are controlled depending on the steam content in the TRF exhaust gas. The volumetric flow rate of the gas mixture through supply means 10 is adjusted, preferably controlled, in the melting operation of the TRF, so that the steam content in the TRF exhaust gas is in the range of 20% to 99%, preferably 50% to 99%. The volumetric flow rate of the gas mixture through supply means 13 is adjusted, preferably controlled, in the oxidation operation of the TRF, so that the steam content in the TRF exhaust gas is in the range of 0% to 25%, preferably 0% to 15%. However, in the reduction operation of the TRF following the oxidation operation, the volumetric flow rate is adjusted, preferably controlled, in the range of 15% to 45%, preferably 15% to 35%.

[0114] The apparatus 1 of Figure 2 may also have a further transfer means 12, which may be designed in the form of a channel or ladle, which serves to transfer the second liquid copper-containing intermediate product 5 from the conversion unit 4, i.e. the TRF, to at least one additional unit, for example an anode casting wheel, for further processing of the copper-containing intermediate product. [Explanation of symbols]

[0115] 1 Copper production equipment 2. Copper-containing starting materials 3 Melting Unit 4. Conversion unit, purification unit 5. The first copper-containing intermediate product in the liquid state within the internal space of the melting unit 6. A liquid second copper-containing intermediate product within the internal space of the conversion unit. 7. Transfer means for transferring the liquid first copper-containing intermediate product; channel or ladle 8. Transfer means for transferring the liquid second copper-containing intermediate product; channel or ladle 9 Hydrogen-containing gas storage or supply connections 10. Supply means for supplying a hydrogen-containing gas, in particular from a renewable source, to the melting unit and / or the conversion unit. 11 Power source; electrical energy from renewable sources 12 Transfer means for transferring the liquid second copper-containing intermediate product; channel or ladle 13 Supply means for supplying hydrogen-containing gas or air / O2, especially from renewable sources, to the melting unit and / or the conversion unit; nozzles

Claims

1. An apparatus (1) for producing copper having a purity of at least 95% from a copper-containing starting material (2), comprising: at least one melting unit (3) for producing a liquid first copper-containing intermediate product (5), at least one conversion unit (4) for producing a second liquid copper-containing intermediate product (6) from said first copper-containing intermediate product; - H ２ , N.H. ３ , H ２ - inert gas mixture, or H ２ or NH ３ and CH ４ and at least one supply means (10, 11) configured to supply an adjustable volumetric flow rate of a hydrogen-containing gas selected from the group consisting of a mixture of 1. The apparatus (1), wherein the volumetric flow rate of the hydrogen-containing gas to the melting unit and / or the conversion unit, set by the supply means, is such that the steam content in the exhaust gas of the melting unit and / or the conversion unit is within a specified target value range.

2. 2. The apparatus according to claim 1, wherein the supply means is a controllable supply means, and the apparatus is configured to determine the steam content in the exhaust gas of the melting unit and / or the converting unit and to control the supply means depending on the determined steam content.

3. 3. The apparatus of claim 1, wherein the apparatus is configured to provide the second liquid copper-containing intermediate product without changing the first copper-containing intermediate product from the liquid to a solid state substance.

4. 4. Apparatus according to any one of claims 1 to 3, wherein the melting unit and / or the converting unit comprises at least one heating device, in particular at least one additional heating device.

5. 5. The device according to claim 4, wherein the heating device and / or the additional heating device are electric heating devices and / or comprise a burner, in particular a gas burner.

6. 6. Apparatus according to claim 4 or 5, wherein the supply means for supplying the melting unit / or the converting unit with a hydrogen-containing gas are formed by the heating device.

7. 7. Apparatus according to any one of claims 1 to 6, wherein the supply means comprises a nozzle, in particular a refining nozzle, and / or is selected from the group consisting of a nozzle, in particular a refining nozzle, a gas burner, a lance, a purging stone, and an impeller.

8. 8. The apparatus according to any one of claims 1 to 7, wherein the apparatus comprises at least one means for determining the vapor content, preferably said means being an FTIR spectrometer and / or comprising an oxygen sensor, a hydrogen sensor, a temperature sensor, or a combination thereof.

9. 1. A method for producing copper having a purity of at least 95%, comprising: a) providing a copper-containing starting material; b) melting the copper-containing starting material in a melting unit to produce a first liquid copper-containing intermediate product having a copper content of 70% or more; c) reducing the first copper-containing intermediate product in a conversion unit to produce a second copper-containing intermediate product having a copper content of 95% or more; During melting and / or reduction, H ２ , N.H. ３ , H ２ - inert gas mixture, or H ２ or NH ３ and CH ４ and a mixture of hydrogen-containing gas and hydrogen-containing gas is supplied to the melting unit and / or the converting unit; 10. The method according to claim 9, wherein the steam content in the off-gas of the melting unit and / or the conversion unit is within a specified target value range.

10. 10. The method of claim 9, wherein the copper-containing starting material is oxidized during melting by supplying an oxygen-containing gas to the melting unit.

11. 11. The method of claim 9 or 10, wherein the first copper-containing intermediate product is oxidized by the conversion unit prior to the reduction in step b) by supplying an oxygen-containing gas to the conversion unit.

12. 12. The apparatus of claim 1 or the method of claim 9, wherein the first copper-containing intermediate product has an oxygen content of 6000 ppm or less and / or the second copper-containing intermediate product has an oxygen content of 2500 ppm or less.

13. 13. The apparatus of any one of claims 1 to 8 or the method of any one of claims 9 to 12, wherein the copper-containing starting material is selected from the group consisting of copper concentrate, copper scrap, or combinations thereof.

14. 14. The apparatus of any one of claims 1 to 8 or the method of any one of claims 9 to 13, wherein the melting unit is selected from the group consisting of a bath melter, an arc furnace, an induction furnace, a TBRC, a TRF, an ETRF, and a ladle furnace.

15. The apparatus of any one of claims 1 to 8 or the method of any one of claims 9 to 14, wherein the converting unit is selected from the group consisting of a PSC, a ladle furnace, an anode furnace, a TBRC, a TRF, and an ETRF.

16. The hydrogen-containing gas is H ２ and CH ４ It is a mixture of ２ The ratio of the hydrogen-containing gas is in the range of 10% to 80%, preferably 25% to 35%, or ３ and CH ４ and NH ３ The device according to any one of claims 1 to 8 or the method according to any one of claims 9 to 15, wherein the ratio of is in the range of 10% to 80%, preferably 25% to 35%.

17. 17. The apparatus of any one of claims 1 to 8 or the method of any one of claims 9 to 16, wherein the second copper-containing intermediate product has a copper content in the range of ≧97.0% to ≦99.9%, preferably ≧98.0% to ≦99.9%, or ≧98.2% to ≦99.8%.

18. the target value of the steam content in the exhaust gas of the melting unit is in the range of 0% to 99%, 50% to 99%, or 0% to 5%; and / or The apparatus according to any one of claims 1 to 8 or the method according to any one of claims 9 to 17, wherein the target value of the steam content in the exhaust gas of the conversion unit during reduction is in the range of 15% to 45% or 15% to 35%.

19. A method according to any one of claims 9 to 18, using a device according to any one of claims 1 to 8.

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