Device and method for producing directly reduced iron ore supports and for melting the directly reduced iron ore supports

Abstract

The invention relates to a device (1) and a method for producing directly reduced iron ore carriers (ri) and for melting the directly reduced iron carriers (ri).

Description

[0001] The invention relates to a device and a method for producing directly reduced iron ore carriers and for melting the directly reduced iron carriers.

[0002] With the ongoing decarbonization of the steel industry, the production of pig iron via blast furnaces will be gradually phased out, and existing blast furnaces will be shut down. This will be replaced by modern and more climate-friendly direct reduction technology using hydrogen and downstream electric arc furnaces (ESF), see, for example, EP 3 954 786 A1. Constructing new facilities using these modern technologies is very expensive.

[0003] In DE 37 20 648 A1, a concept idea has been proposed to convert existing blast furnaces into smelting gasifiers in order to utilize these blast furnaces and their further use as smelting gasifiers for the gasification of briquetted household waste, household-like waste, special waste and / or agricultural raw materials.

[0004] It would therefore be desirable to be able to provide comparable technologies with lower investment costs.

[0005] The task is therefore to provide a device and a method for producing directly reduced iron ore carriers and for smelting the directly reduced iron carriers, which are in particular more cost-effective than a comparable new construction.

[0006] The problem is solved with a device according to claim 1 and with a method according to claim 10. Further advantageous embodiments are described in the dependent claims.

[0007] According to a first teaching, the invention relates to a device for producing directly reduced iron ore carriers and for melting the directly reduced iron carriers, in which a direct reduction area is arranged in an upper section of the device and a melting area is arranged in a lower section of the device, wherein a gas-permeable dome shape is arranged above the melting area, which spatially separates the direct reduction area from the melting area, wherein the melting area is divided by a lower liquid area and an upper gas area above it.

[0008] According to a second teaching, the invention relates to a method for producing directly reduced iron ore carriers and for melting the directly reduced iron carriers, wherein a direct reduction area is arranged in an upper section of a device and a melting area is arranged in a lower section of the device, wherein the direct reduction area is spatially separated from the melting area by arranging a gas-permeable dome shape, wherein directly reduced iron carriers are discharged from the direct reduction area into the melting area via at least one discharge opening and / or discharge flap in the dome shape and / or at least one discharge opening and / or discharge flap in the device wall.

[0009] The previously known technologies for producing directly reduced iron ore carriers, such as in direct reduction plants of known design, including shaft furnace direct reduction technology from Midrex or HYL, and for melting the directly reduced iron carriers, such as in electric furnaces of known design, including type EAF or SAF, and thus requiring at least two different units, can be replaced or substituted by one device, thereby providing a more cost-effective alternative to a comparable new building.

[0010] The direct reduction section in the upper part of the device corresponds to a reactor in a substantially comparable direct reduction plant. The division of the melting zone into a lower liquid zone and an upper gas zone above it creates an analogy to an electric arc furnace. The gases generated in the melting zone in the lower part of the device during the melting of the directly reduced iron supports and additives, whether due to the process itself or through the additional supply of external gases, are preferably reducing and thus ideally suited to be passed as reducing gas through the direct reduction zone located in the upper part of the device and through the iron supports to be directly reduced within it. The gas-permeable dome shape therefore allows gases from the melting zone to pass through into the direct reduction zone.The gas-permeable dome shape can be seen as a kind of vault over the melting area.

[0011] According to a preferred embodiment, the device is a shaft furnace. As is already known from the prior art, repurposing existing shaft furnaces is suitable, particularly repurposing blast furnaces, since these can be converted relatively easily to meet the requirements of the process according to the invention. In the known blast furnace process, iron ores are continuously produced into liquid pig iron through reduction and smelting processes. The continuously operating shaft furnace is based on the countercurrent principle. Burden and coke are fed alternately in layers across the furnace cross-section at the top opening of the shaft, the so-called top plate. Due to gravity, the fed material sinks downwards against the rising reduction gases.The burden consists of iron ore carriers (such as lump ore and / or agglomerated ores in the form of sinter and / or pellets) and additives (such as gravel, dolomite, bauxite, and olivine). The added coke serves as an energy carrier and reducing agent. At the top, the reducing gas produced in the blast furnace process and partially consumed through redox reactions with the burden is drawn off as so-called top gas. In the lower part of the blast furnace, the hearth, preheated air, possibly mixed with unheated air, steam, and / or oxygen, is supplied via tuyeres from hot blast stoves. This air provides the necessary oxygen for combustion and sensible heat. Upstream of the tuyeres, the carbon reacts with the supplied oxygen to form carbon monoxide, which rises and reduces the iron ore by forming carbon dioxide.During the descent of the burden, the iron ore is reduced to metallic iron, carburized, and melted. The iron impurities of the ore, known as gangue, such as silicon dioxide, manganese oxide, and phosphorus oxide, are also reduced by the reducing gas and dissolved in the pig iron. Unreduced gangue components, together with the fluxes, form molten slag. This binds unwanted impurities and carries them out of the process. Liquid pig iron and slag are sequentially discharged from the furnace through a taphole in the lower section, the hearth. The products of the blast furnace include pig iron, slag, blast furnace gas, and blast furnace dust. A classic blast furnace, viewed from top to bottom, is divided into the top, the shaft (preheating zone, reduction zone, and carburizing zone), the coal sack, the hearth (melting zone), and the hearth.The transition from the solid to the liquid phase is described by the so-called cohesive zone, in which the melting and softening of the burden and (partially) reduced iron ore carrier occurs. The location of the cohesive zone depends on the prevailing temperature ranges in the blast furnace and is therefore determined by the blast furnace operation and design. The cohesive zone consists of permeable, gas-permeable coke layers interspersed with viscous, molten burden materials and iron, which oppose the gas flow. Therefore, the cohesive zone has a significant influence on the gas distribution in the lower part of the shaft. By installing a gas-permeable dome, the direct reduction zone is spatially separated from the melting zone, so that there is no continuous transition between the individual sections mentioned above during the blast furnace process.Furthermore, there is the possibility of a flow-optimized design of the dome to ensure the best possible gas purging of the shaft, similar to a cohesive zone.

[0012] The use of this technology is particularly advantageous because the dome provides the support structure for the burden column, which in the conventional blast furnace process is provided by the dead man's block (static coke bed). Therefore, when using hydrogen and / or hydrogen-containing gases, no water-gas shift reaction occurs, which reforms the water vapor produced during reduction into hydrogen at the cost of coke / carbon consumption.

[0013] By selectively injecting or otherwise introducing carbon / carbon carriers directly into the melt, efficient carburization of the iron melt occurs. Simultaneously, a chemically reducing atmosphere is created above the iron melt. This chemically reducing atmosphere can also be achieved when carbon is completely omitted, since in this design hydrogen / hydrogen-containing gases can be selectively injected / introduced directly above the melt surface to precisely control the reducing atmosphere.

[0014] Using the above-mentioned methods, it is therefore possible to produce slags that can be processed in a cement plant (low iron oxide content) despite the absence of carbon in the melt.

[0015] With low iron oxide contents in the slag, it is well known to experts that additives / slag formers from the group consisting of MgO, SiO₂, Al₂O₃, and CaO can be used to achieve favorable properties for both process engineering and cement production. Thus, the conditioned slag from the reactor can be used as a substitute for blast furnace slag after appropriate granulation.

[0016] The slag and pig iron produced in the blast furnace according to the invention can be conveyed to existing processing units via existing means, such as existing tapping troughs for filling slag ladles with slag and torpedo ladles with pig iron. The slag produced can be fed in liquid form to a known slag conditioning process as needed. The slag can be wet- or dry-granulated using known methods. The pig iron can also be conveyed to known processing stages, such as vacuum treatment, refining in a converter, and / or in an electric arc furnace, for example, of type EAF. Furthermore, the existing charging equipment of the blast furnace, starting with conveyor systems, bunker systems, and charging systems such as bell-type and / or bellless charging systems (see htt) can be used. ps: / / www.paulwurth.com / wp-content / uploads / 2020 / 08 / Brochure-Bell-Less-Top-Charging-System-en.pdf or https: / / www.danieli-corus.com / ironmaking / top-charging-unit) can be used. Furthermore, the existing blast furnace gas extraction and processing facilities, i.e., raw gas pipelines and processing plants (such as exhaust gas traps, risers, and downstream processing plants for separating solids (blast furnace dust) and processing the blast furnace gas), can continue to be used. Thus, only the upgrading / repurposing of a blast furnace into a modern and environmentally friendly device for producing directly reduced iron ore carriers and for smelting the directly reduced iron carriers according to the invention would be necessary, whereby the entire periphery around the blast furnace with all its existing equipment could be retained.

[0017] According to one embodiment, the dome shape can be self-supporting. For this purpose, the dome shape can be assembled using a tongue-and-groove system, designed to accommodate the pile of iron beams to be directly reduced in the direct reduction zone and, in particular, to withstand mechanical and thermal influences. A connection to and / or contact with the device, or with the inner wall or the (standard) refractory material designed as the inner wall, can be provided in the area of ​​the so-called rest if a blast furnace has been repurposed as a device.

[0018] Depending on the design, either alternatively or additionally, the dome can be constructed with a substructure. This substructure can fully or partially bear the load of the dome and the iron girders supporting the fill above it. Here, too, the dome and substructure are designed to withstand mechanical and thermal stresses.

[0019] The material for the dome shape and the optional substructure can be made of a refractory material. A composite material containing or consisting of steel and a refractory matrix would also be conceivable. Alternatively, a wear-resistant material such as steel or a nickel-chromium superalloy like Inconel could be used. The dome shape and the optional substructure can also be equipped with cooling channels.

[0020] According to one embodiment, the dome shape can be inverted with its apex pointing towards the melting zone. This configuration must be connected to a suitable substructure within the device to ensure stable separation of the melting zone from the direct reduction zone.

[0021] In contrast to the blast furnace process, the approach according to the invention discussed here is not a continuous direct reduction and melting process. The iron carriers to be directly reduced, located in the upper section of the apparatus within the direct reduction zone, are exposed to a reducing gas for a defined period of time. This gas is supplied from the melting zone via the substantially gas-permeable dome. If the directly reduced iron carriers exhibit predefined properties, such as a minimum metallization degree of 70%, in particular 75%, preferably 80%, more preferably 85%, and most preferably 90%, they are transferred to the melting zone and melted in the lower liquid zone of the melting zone, together with the addition of additives, to produce pig iron and a slag floating on the pig iron.The procedure is analogous to that of the individual units direct reduction and electric arc furnace, but integrated into a single device. The tapping of pig iron and slag can be carried out in the lower liquid zone of the melting chamber of the device, similar to the electric arc furnace. If a repurposed blast furnace is used, the existing tapping areas can be adopted, or suitable tapping devices can be added, similar to those used in the electric arc furnace.

[0022] The degree of metallization corresponds to the ratio of pure iron to total iron in the directly reduced iron carrier. The degree of metallization can be determined during the ongoing process based on the FeO content in the slag or the reducing agent consumption in the melting range and can, for example, be taken into account as a control parameter.

[0023] The iron carriers to be directly reduced are provided, for example, in the form of pellets and / or lump ores and / or sinter and are introduced into the direct reduction area in the upper section of the device.

[0024] The directly reduced iron beams can be discharged from the direct reduction area into the melting area via at least one discharge opening and / or discharge flap in the dome shape and / or at least one discharge opening and / or discharge flap in the device wall.

[0025] According to one embodiment, at least one discharge opening and / or discharge flap can be arranged in the dome shape to remove the directly reduced iron ore carriers from the direct reduction area to the smelting area.

[0026] According to a further embodiment, at least one discharge opening and / or discharge flap can be arranged in the device wall for the discharge of the directly reduced iron ore carriers from the direct reduction area into the smelting area.

[0027] According to a further embodiment, at least one discharge opening and / or discharge flap can be arranged in the dome shape and at least one discharge opening and / or discharge flap in the device wall for discharging the directly reduced iron ore carriers from the direct reduction area into the melting area. By providing the combined discharge through the dome shape and device wall, a potential complete blockage caused, for example, by locally occurring agglomeration of the directly reduced iron carriers can advantageously be avoided or counteracted.

[0028] To implement the principle of an electric arc furnace and ensure the melting of the directly reduced iron supports, electrodes are arranged in the melting zone according to a preferred embodiment. In the case of using a repurposed blast furnace, these electrodes can be inserted through suitable openings in the furnace wall, for example, through a portion of the existing wind tuyeres. The openings are to be designed and / or adapted such that a preferably inclined or angled arrangement of the electrodes in the melting zone is possible, preferably at an angle between 30 and 60° to the horizontal. The electrodes can be made of graphite. Alternatively, they can also be made of Söderberg electrodes.The electrodes are positioned through openings in the furnace wall in the upper gaseous zone of the melting zone to prevent the unintentional escape of slag and, optionally, pig iron through these openings. However, the electrodes can extend into the lower liquid zone of the melting zone, allowing contact between the electrode tips and at least the slag. This means the electrodes can protrude into the slag in the liquid phase and / or into the bed before the solids (directly reduced iron carriers and additives) introduced into the melting zone are liquefied, and this may even be desirable depending on the operating mode. Contact between the electrodes and the bed, or at least the slag, is also a known operating mode in a known electric arc furnace (electric reduction furnace) of the SAF type.

[0029] In the case of Söderberg electrodes, the electrode mass can be enhanced, for example, by the addition of metallic wires and / or braids, thereby increasing its strength and / or improving its thermal conductivity. The in-situ fabrication or provision of Söderberg electrodes is state of the art. Additionally, alloying elements could be introduced into the melt by adding metallic wires.

[0030] Alternatively or additionally, ceramic components or ceramic fibers can also be included in the electrode mass to reinforce the electrodes and / or to adjust the wear characteristics.

[0031] Preferably, at least one component from the group consisting of SiO₂, CaO, MgO, and Al₂O₃ can also be included as a ceramic component in the electrode mass. This allows, for example, a reduction in the amount of slag formers required to condition the slag to be produced in the melting zone of the device.

[0032] Slag components, which contain components from the group SiO 2 , CaO, MgO, Al 2 O 3, especially finely ground, may also be added, particularly preferably.

[0033] Furthermore, according to a preferred embodiment, material feed openings are arranged in the melting zone. Additives can be introduced through these openings. If a repurposed blast furnace is used, these additives can be introduced via suitable openings in the furnace wall, for example, through a portion of the existing tuyeres.

[0034] The additives are slag formers comprising or consisting of at least one component from the group consisting of SiO₂, CaO, MgO, and Al₂O₃. Slag formers are preferably added such that a basicity B4 in the processed slag is between 0.7 and 4.5. B4 can be at least 0.8, preferably at least 0.9, and particularly at most 3.7, preferably at most 2.6, and preferably 1.8. The basicity B4 corresponds to the ratio of CaO + MgO to SiO₂ + Al₂O₃, the determination of which characteristic values ​​is generally known to those skilled in the art in solid-state slags. The slag produced during melting can be conditioned by additives to replicate a blast furnace-like slag (such as OBF), which can be subjected to dry / wet granulation and thus, through rapid solidification, yields granulated blast furnace slag with latent hydraulic properties as a product.

[0035] In addition to slag formers, the additives can optionally include carbon-containing materials. Suitable carbon-containing materials include, in principle, all materials in gaseous, liquid, and / or solid form containing reducible free carbon that can be introduced into the melting range of the device. Examples of solid materials include coke, coke dust, coke grit, coke slurry, coal, coal particles, biochar, recycled plastics, biomass, plastics, or mixtures thereof. Examples of liquid materials include ethanol, methanol, and other (suitable) hydrocarbons or mixtures thereof. Examples of gaseous materials include carbon-containing gases such as carbon dioxide, methane (natural gas), carbon monoxide, propane, butane, or mixtures thereof.The optional carbon-containing feedstocks are introduced, for example, in an amount sufficient to achieve a defined carbon content in the pig iron to be produced, which may be between > 0, in particular > 0.50, preferably > 1.0, preferably > 2.0, particularly preferably > 3.0 and 4.8 wt.%.

[0036] The additives can include slag formers, optional carbon-containing feedstocks, and optional iron-containing metallurgical residues and / or recyclable materials. Preferably, iron-containing metallurgical residues and / or recyclable materials containing or consisting of oxygen compounds are present in oxide form. These include, for example, iron-containing agglomerates or oxide recyclable materials generated in a metallurgical complex, particularly dusts. Dusts are defined as substances with a diameter of less than 10 mm, particularly less than 6 mm. Dusts can originate from steelworks, sintering and pelletizing plants, direct reduction plants, electric arc furnaces, coking plants, and blast furnaces. Other metallurgical residues can include scale (rolling scale), slag from secondary metallurgy, or desulfurization.

[0037] To improve or increase the recycling rate, scrap metal can optionally be added as an additive in addition to the slag formers, optional carbon-containing feedstocks, and optional iron-containing metallurgical residues and / or metallurgical recycling materials. This can be achieved, for example, by adding > 0 kg, in particular at least 20 kg, preferably at least 50 kg, preferably at least 80 kg up to 200 kg, in particular up to 150 kg, preferably up to 100 kg of scrap metal per ton of pig iron to be produced.

[0038] If insufficient gas is generated in the melting zone, which accumulates in the upper gas zone of the device and is subsequently passed through the direct reduction zone as reducing gas, additional additive gas, for example in the form of carbon monoxide, hydrogen, natural gas, or CO- and / or H₂-containing blast furnace gases, can be introduced into the upper gas zone of the melting zone. These can also be introduced through suitable openings in the device / blast furnace wall if a repurposed blast furnace is used, for example, via a portion of the existing tuyeres.The additional gas introduced can already have a temperature between 200, in particular 300, preferably 400, preferably 500, particularly preferably 600, more preferably 700 and 1200 °C, which is either heated to temperature via suitable and known process gas heaters or drawn directly from the heat of the preceding process.

[0039] The process gas (blast furnace gas) extracted in the upper section of the apparatus, i.e., above the direct reduction zone, can be dehumidified using known methods. This means that the water (vapor) content is reduced, and unwanted components such as carbon dioxide, etc., are also removed from the process gas using known methods. The dehumidified and / or purified process gas can optionally be reheated and returned to the apparatus as a gas, additive gas, or a portion thereof, thus maintaining a closed loop. The extracted process gas may contain unreacted carbon monoxide and / or hydrogen, which can be reused as a reducing gas or for other purposes.

[0040] The invention will now be explained in more detail using exemplary embodiments.

[0041] Figure 1This document describes an exemplary embodiment of a device (1) and a method for producing directly reduced iron ore carriers (ri) and for melting the directly reduced iron carriers (ri). The device (1) is a shaft furnace, preferably a converted blast furnace. A direct reduction section (2) is arranged in an upper section (1.1) of the device (1), and a melting section (3) is arranged in a lower section (1.2) of the device (1). A gas-permeable dome (4) is arranged above the melting section (3), spatially separating the direct reduction section (2) from the melting section (3). The melting section (3) is subdivided by a lower liquid section (3.2) and an upper gas section (3.1) above it. The dome (4) can be self-supporting or provided with a substructure not shown here. For example, the gas-permeable dome (4) is arranged in the area of ​​the blast furnace's rest.

[0042] The exemplary design in Figure 2 shows in comparison to Figure 1 An arrangement of an inverted dome shape (4') with its apex pointing towards the melting area (3). The inverted dome shape (4') can be provided with a corresponding substructure, not shown here.

[0043] Direct-reducible iron carriers (io) are preferably introduced in the form of pellets and / or sinter and / or lump ores into the upper section (1.1) of the device (1) to remain in the direct reduction zone (2) of the device (1) for a specific period of time. During this period, they are brought into contact with a reduction gas, thereby metallizing to form directly reduced iron carriers (ri) with a degree of metallization of at least 70%.

[0044] The gases generated in the melting zone (3) in the lower section (1.2) of the device (1) during the melting of the directly reduced iron carriers (ri) together with additives, due to the process and / or by the additional supply of additive gases (7) from the outside, are preferably reducing and thus ideally suited to be passed as reducing gas through the direct reduction zone (2) arranged in the upper section (1.1) of the device (1) and the directly reduced iron carrier (io) located therein. The gas-permeable dome shape (4, 4') thus allows gases from the melting zone (3) to pass into the direct reduction zone (2). In the liquid zone (3.2) of the melting zone (3), pig iron (R) and a slag (S) floating on it are produced.

[0045] The directly reduced iron beams (ri) can be discharged from the direct reduction area into the melting area via at least one discharge opening and / or discharge flap (4.1) in the dome shape (4, 4`) and / or at least one discharge opening and / or discharge flap (1.4) in the device wall (1.3), see Figure 3 , which shows an exemplary top view of the dome shape (4) according to Figure 1 shows.

[0046] Figure 4Figure 3 shows an exemplary top view of the gas section (3.1) of the melting section (3), which in a blast furnace can correspond to the plane of the former wind tuyeres, so that existing openings can be used and / or adapted to arrange electrodes (5) in the melting section (3), as well as material feed openings (6) through which slag formers, optional carbon-containing feedstocks, optional scrap, and optional iron-containing metallurgical residues and / or recycled metallurgical materials can be introduced. Additional gases (7), which can serve as additives to the gases generated in the liquid section (3.2) during the process and are introduced as reducing gases for reducing the iron carriers (10) to be directly reduced in the direct reduction section (2) of the device (1), can also be supplied externally. In this example, six electrodes (5), six inlets for the additional gas (7), and twelve material feed openings (6) for solids are provided.Naturally, the number (5) to (7) can be individually adapted to the device (1).

[0047] The process gas (blast furnace gas) drawn off in the upper section (1.2) of the device (1) can be dehumidified using known means (10), i.e., the water (vapor) content is reduced, and undesirable components such as carbon dioxide, etc., are also removed from the process gas using known means (11). The dehumidified and / or purified process gas can optionally be reheated and returned to the device (1) as additive gas (7) to maintain a cycle. If required, the additional additive gas (7) supplied from the outside can be heated to a temperature between 200 and 1200°C by a known process gas heater (12). For example, a portion of the dehumidified and / or purified process gas can be used as fuel gas for the process gas heater, as shown in the dashed lines in the Figures 1 and 2The recycled gas can also be mixed with a fresh gas (FG), for example in the form of carbon monoxide, hydrogen, natural gas, or blast furnace gases containing CO and / or H₂. If the extracted process gas is not recirculated but used for other purposes, only fresh gas (FG), with optional heating in a process gas heater (12), can be introduced as an additional additive gas (7) into the upper gas range (3.1) of the melting range (3), see the example in the Figures 1 and 2 .

[0048] In Figure 5An exemplary longitudinal section through a possible arrangement of an electrode (5), for example a graphite electrode or preferably a Söderberg electrode, is shown. Preferably, the electrodes (5) are arranged at an angle between 30° and 60° to the horizontal in the melting zone (3). The electrodes (5) can be arranged down to the lower liquid zone (3.2) of the melting zone (3), so that contact between the tips of the electrodes (5) and at least with the slag (S) can occur. The electrode material (5.1) can, for example, be enhanced by the additional provision of metallic wires and / or braids (5.2) to increase strength and / or improve thermal conductivity. Baking of Söderberg electrodes (5) is carried out using known means (5.3).

[0049] The invention essentially focuses on the integration of a combination of a direct reduction plant and an electric furnace into a restructured blast furnace, particularly since the existing periphery of the former blast furnace process can still be used.

Claims

1. Device (1) for producing directly reduced iron ore carriers (ri) and for melting the directly reduced iron carriers (ri), in which a direct reduction area (2) is arranged in an upper section (1.1) of the device (1) and a melting area (3) is arranged in a lower section (1.2) of the device (1), characterized by the fact that A gas-permeable dome shape (4, 4`) is arranged above the melting area (3), which spatially separates the direct reduction area (2) from the melting area (3), wherein the melting area (3) is subdivided by a lower liquid area (3.2) and an upper gas area (3.1) above it.

2. Device according to claim 1, wherein the device (1) is a shaft furnace, in particular a repurposed blast furnace.

3. Device according to one of the preceding claims, wherein the dome shape (4) is self-supporting.

4. Device according to one of the preceding claims, wherein the dome shape (4) is provided with a substructure.

5. Device according to one of the preceding claims, wherein the dome shape (4') is arranged inverted with a vertex pointing towards the melting area (3).

6. Device according to one of the preceding claims, wherein at least one discharge opening and / or discharge flap (4.1) is arranged in the dome shape (4, 4`) for discharging the directly reduced iron ore carriers (ri) from the direct reduction area (2) into the melting area (3).

7. Device according to one of the preceding claims, wherein at least one discharge opening and / or discharge flap (1.4) is arranged in the device wall (1.3) for the discharge of the directly reduced iron ore carriers (ri) from the direct reduction area (2) into the melting area (3).

8. Device according to one of the preceding claims, wherein electrodes (5) are arranged in the melting area (3).

9. Device according to one of the preceding claims, wherein material supply openings (6) are arranged in the melting area (3).

10. Method for producing directly reduced iron ore carriers (ri) and for melting the directly reduced iron carriers (ri), wherein a direct reduction area (2) is arranged in an upper section (1.1) of a device (1) and a melting area (3) is arranged in a lower section (1.2) of the device (1), characterized by the fact thatThe direct reduction area (2) is spatially separated from the melting area (3) by arranging a gas-permeable dome shape (4, 4`), wherein directly reduced iron supports (ri) from the direct reduction area (2) are discharged into the melting area (3) via at least one discharge opening and / or discharge flap (4.1) in the dome shape (4, 4`) and / or at least one discharge opening and / or discharge flap (1.4) in the device wall (1.3).

11. Method according to claim 10, wherein the melting area (3) is divided by a lower liquid area (3.2) and an upper gas area (3.1) above it, wherein an additional gas (7) is introduced into the gas area (3.1).

12. Method according to claim 11, wherein the additive gas (7) has a temperature between 200 and 1200 °C, for example in the form of carbon monoxide, hydrogen or CO and / or H2-containing blast furnace gas.

13. Method according to claim 11 or 12, wherein slag formers comprising or consisting of at least one component from the group SiO2, CaO, MgO, Al2O3 are introduced into the gas region (3.1) as an additive.

14. Method according to claim 13, wherein carbon-containing feedstocks are introduced into the gas section (3.1) in addition to slag formers as additives in order to achieve a defined carbon content in the pig iron (R) to be produced, which may be between > 0 and 4.8 wt.%.

15. Method according to claim 13 or 14, wherein scrap is introduced into the gas section (3.1) as an additive alongside slag formers and optionally carbon-containing feedstocks, with > 0 kg up to 200 kg of scrap per tonne of pig iron (R) to be produced.

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