Electric stove

Abstract

1. An electric stove for heating a reducing gas, comprising: a hollow metal shell body extending along a longitudinal direction; a refractory lining disposed on an inner surface portion of the shell body; and a plurality of bricks disposed in adjacent layers extending along the longitudinal direction, each brick including a plurality of cavities extending straight along the longitudinal direction through a respective layer, the cavities of adjacent layers being aligned with one another, thereby forming a plurality of channels for directing the reducing gas; wherein the electric stove further comprises a plurality of heating wires for heating the reducing gas, each heating wire having a diameter smaller than a diameter of the channels, each heating wire extending at least partially through at least one corresponding channel of the plurality of channels such that, when the electric stove is operating, a predetermined amount of heat is dissipated by each heating wire into the reducing gas flowing around the heating wire.

Description

[Technical Field]

[0001] The present invention relates to an electric stove, and in particular to an electric stove for heating reducing gases to be injected into a metallurgical furnace. [Background technology]

[0002] According to recent developments in the metallurgical industry, steelmakers aim to reduce greenhouse gas emissions that are considered harmful to the environment, such as carbon dioxide. As a result, steelmakers aim to use "green" (electrical) energy sources in the manufacture of metallurgical products. Indeed, future steel production will likely focus on the use of low-carbon production methods combined with the use of sustainable energy sources. In this context, the use of direct reduction processes based on reducing gases, including H and / or syngas, is also envisioned.

[0003] In the prior art, combustion heaters and regenerative heat exchangers (such as hot air stoves) are known for heating process gases on an industrial scale. However, these heaters require the combustion of fuel. Furthermore, most commercially available devices powered by electrical energy appear to be unsuitable for heating reducing gases to sufficient temperatures or do not address the requirements of "heavy" industry. For example, most of these devices are not scalable to the multi-MW sizes required to process large volumes of gas. Furthermore, most devices are not suitable for heating dusty gases (i.e., gases containing between 0 mg and 5 mg solids / Nm3). Therefore, no known devices address the requirements for electrical heating of gases in terms of flow rate, power scale, dust content, output temperature, or other specific layout requirements. Therefore, it is desirable to provide a solution to overcome these drawbacks. Object of the invention

[0004] It is an object of the present invention to provide a heater that is configured or suitable for heating gas on an industrial scale. This object is achieved by an electric stove as defined by the independent claims. Summary of the Invention

[0005] The proposed electric stove, configured or suitable for heating a (reducing) gas, includes a hollow metal shell body extending along a longitudinal direction, a refractory lining disposed within the shell body, and a plurality of bricks disposed in adjacent layers extending along the longitudinal direction. Each brick includes a plurality of cavities extending straight along the longitudinal direction through its respective layer. The cavities in adjacent layers align with each other to form a plurality of channels for guiding the (reducing) gas. The electric stove further includes a plurality of heating wires for heating the (reducing) gas, each heating wire having a diameter smaller than the diameter of the channel. Each heating wire extends at least partially through at least one corresponding channel of the plurality of channels such that a predetermined amount of heat is dissipated by each heating wire into the reducing gas flowing around the heating wire when the electric stove is operating.

[0006] It has been found that the proposed arrangement makes it possible to provide a heating stove for heating (reducing) gases with a particularly compact design, which in turn allows for a space-saving installation in industrial facilities. Furthermore, it has been found that the present arrangement is also scalable as needed and / or when certain amounts of (reducing) gases have to be heated.

[0007] The proposed configuration also allows for the introduction of gases together with other compounds, such as dust-containing gases. For example, no known prior art device allows for the heating of reducing gases containing dust. In order for the dust-containing gases flowing through the bricks to be heated in the stove, a certain minimum size of the cavity must be ensured.

[0008] Furthermore, the proposed configuration may operate in direct reduced iron (DRI) production and / or (blast) furnace plants, especially those with syngas injection systems. As a result, the proposed configuration allows for heating process gases based on sustainable (e.g., "green") energy sources, thereby replacing conventional fuel-based systems. Therefore, the negative environmental impact caused by classical heaters may be significantly reduced.

[0009] "Reducing gas" generally refers to any chemical medium with reducing properties. For example, the reducing gas may be a gas containing hydrogen and / or carbon monoxide, correspondingly, a synthesis gas. It should be noted that the electric heater is not limited to the treatment of reducing gases. It can also heat other gases, particularly process gases, such as CO2, CO, N2, O2, H2O, and H2, for different industrial processes.

[0010] "Hollow metal shell body" may generally refer to the frame or reservoir of an apparatus or reactor in which the (reducing) gas is heated.

[0011] The "longitudinal direction" may generally refer to the main length direction along which the shell body extends. In other words, the longitudinal direction may be defined by the direction along which the electric heater extends. For example, when the electric heater is installed horizontally, the longitudinal direction may be horizontal or parallel to a horizontal surface such as the ground.

[0012] The term "refractory lining" may generally refer to one or more layers of high-temperature resistant material, such as refractory bricks. The refractory lining may be disposed on at least a portion or the entire inner surface of the shell body. Alternatively, one or more layers of insulating lining may be disposed between the refractory lining and the steel shell, and the insulating lining may include a layer of insulating bricks and a layer of castable ceramic. Furthermore, for example, the refractory lining may include one or more layers of different bricks having insulating and / or insulating properties. Note that the refractory lining may generally be selected based on the operating temperature, which may also allow for the use of different materials along the heater length, correspondingly, the longitudinal direction. In particular, the refractory material may include various grades of high-alumina refractories that do not tend to react with hydrogen. The bricks of the refractory lining may be specifically configured to support multiple bricks, correspondingly, checker bricks, that guide the heating wire.

[0013] "Multiple bricks" may generally refer to the quantity of checkered bricks or similar brick-like elements. Each brick may have multiple cavities, correspondingly through holes or openings. The cavities may have a circular or semicircular shape. Additionally or alternatively, each brick may also have so-called "half cavities" located at the edge of the brick and representing half of the overall cavity shape. Two half cavities or half cavities of two adjacent bricks may be used to form an entire cavity. It is understood that the cavities may also have other shapes. All cavities may extend along a direction parallel to the longitudinal direction. This configuration may allow the cavities of adjacent bricks in adjacent layers to be aligned with each other, thereby forming multiple channels for guiding (reducing) gases. In this context, "channel" generally refers to a linear passage extending through several brick layers, where the channel is formed from adjacently arranged cavities and / or half cavities.

[0014] A "layer" may generally refer to a course, correspondingly a level, correspondingly a structure, including a predetermined amount of bricks, the bricks defining the structure being aligned with one another. It is understood that layers may have the same length along their length. However, there may be embodiments in which layers have different lengths.

[0015] The term "multiple heating wires" generally refers to metal threads or rods configured to heat by electrical conduction. The wires may be disposed within channels formed by the bricks. Therefore, the heating wires may preferably have a diameter smaller than the diameter of the channel or cavity. This configuration allows the gas to flow substantially around the wires. When the electric heater is operating, each heating wire extends at least partially through at least one of the multiple channels so that a predetermined amount of heat is dissipated by each heating wire into the (reducing) gas flowing around the heating wire. In this context, it should be noted that the heating wire material may be selected from a wide range of materials. In particular, the wire material may be suitable for withstanding high temperatures and / or reactions with the component(s) of the process gas, correspondingly the reducing gas. For example, it is known that the lifespan of wires is shortened when the wires are frequently exposed to gases with a high nitrogen concentration. The nitrogen content in the (reducing) gas may still be kept low (≦10%) and the maximum gas temperature may be kept in the range of 800° C. to 1000° C., preferably 900° C. Alternatively, the heating wires may be configured to operate at other temperatures, for example lower temperatures.

[0016] In one embodiment, at least two adjacent bricks in a corresponding layer each have a half-cavity, and the at least two adjacent bricks are aligned with each other such that the half-cavities of the respective bricks form an entire cavity. The half-cavities may be located in the edge regions of the bricks.

[0017] The term "corresponding layer" generally refers to a layer in which two bricks with half cavities at the edge regions are placed adjacent to each other so that two half cavities form openings corresponding to one cavity. By arranging the half cavities, efficient use of space within the shell body can be achieved.

[0018] In one embodiment, the diameter of the channel is between 1 and 5 times larger than the diameter of the heating wire. A channel with a diameter larger than the diameter of the heating wire allows the dust gas to be heated efficiently and without the risk of clogging the channel with dust that may have settled in the channel. Thus, the gap between the wire and the refractory lining may have a size in the range of 4 millimeters to 40 millimeters.

[0019] In one embodiment, an insulating lining is disposed between a portion of the interior surface of the metal shell body and the refractory lining. The insulating lining may include one or more layers of insulating material or insulating structural elements. For example, the insulating lining may include a first layer of insulating castable ceramic and a second layer of refractory brick.

[0020] In one embodiment, the electric stove has a gas inlet fluidly connected to a distribution ring, the distribution ring including a plurality of supply ports configured to direct (reducing) gas to a first end of the shell body, and a gas outlet at a second end of the shell body, the gas outlet extending along the longitudinal direction. The term "end" refers to the leading end of the shell body. By placing the distribution ring at the first end, the incoming heated gas is uniformly distributed and directed into the channels. In alternative embodiments, for example, embodiments with smaller dimensions, the installation of a distribution ring may not be necessary.

[0021] In one embodiment, one or more of the multiple heating wires or each electric heating wire has a U-shaped portion positioned opposite or at the gas outlet. "U-shaped" generally refers to the shape of the wire section, i.e., a shape that allows two parallel-extending wires to be connected to each other. By providing a U-shaped portion, which may be integral with the wire or alternatively applied / positioned on the wire, it is possible to provide the electrical contact module at only one position within the shell body, preferably near the gas inlet. This ensures that the electrical contact module is not exposed to the significantly higher temperature of the heated (reducing) gas near the gas outlet. Therefore, the U-shaped portion is preferably positioned opposite or at the gas outlet. In this context, the term "opposite" means that the apex of the U-shaped portion can face the direction of the gas outlet. In this context, the term "at" means that the U-shaped portion can be positioned proximate to the gas outlet.

[0022] In one embodiment, multiple electric heating wires are arranged in series and / or parallel, and since the arrangement may be connected in series and / or parallel, an optimum electrical resistance may be established to achieve a suitable Joule effect.

[0023] In one embodiment, the electric heater is configured to operate at low voltage using one of single-phase AC, three-phase AC, or DC. In particular, three-phase or single-phase AC may be readily available from the power distribution network. Alternatively, a suitable design may be configured for DC. If DC is used, dedicated equipment may be provided upstream of the electric heater to convert the AC from the network into DC.

[0024] In one embodiment, the electric heater further comprises a centering element for preventing the electric heating wire from contacting the wall of the channel in which it is located. Each channel may preferably include one or more such centering elements, which may be longitudinally spaced apart from one another by, for example, 25 cm to 150 cm. It should be noted that the centering elements may alternatively be closer to one another or farther apart from one another.

[0025] The term "centering element" refers to an element that may have a brick-like structure, excluding cavities and corresponding semi-cavities. The cavities and / or semi-cavities of the centering element may have a different form from the cavities and / or semi-cavities of the brick. For example, the cavities of the centering element may have pins, protrusions, projections, bulges, etc., to mount the electric heating thereon while at the same time limiting the channel as much as possible. Alternatively, the cavities of the centering element may have a circular shape with a diameter slightly smaller than that of the brick cavity. The centering element may hold the heating wire in a substantially central position in the channel. Alternatively, the term "centering element" may also refer to a device placed on the wire that supports and centers the wire relative to the channel walls. In this case, the centering element may be an element made of one of the following materials: metal, plastic, resin, or a mixture thereof. The centering element prevents excessive bending and / or creep deformation of the wire by ensuring proper support. As a result, uniform cooling of the wire may occur. As a further result, the occurrence of hot spots may be prevented, resulting in a significantly extended lifespan of the wire. It should be noted that the centering element may have a high electrical resistance and / or be selected from and / or include a highly electrically resistive material to avoid short circuits between the wires in adjacent cavities.

[0026] In an embodiment, the shell body has a diameter in the range of 0.5 m to 4 m, preferably in the range of 1.50 m to 2.50 m, and most preferably 2 m, and the shell body has a length in the range of 5 m to 12 m, preferably in the range of 6 m to 10 m, and most preferably 7 m. The dimensions of the shell body may be adjusted to suit requirements by scaling.

[0027] In an embodiment, the electric heater further includes an electrical connection module for providing electrical contacts to the electric heating wire, the electrical connection module being disposed in the first end portion near the plurality of supply ports and spaced apart from the layer. By locating the electrical connection module at a cooler end of the shell body, the temperature load on the electrical connection module is kept relatively low, which may lead to a longer life.

[0028] In an embodiment, the shell body of the electric stove is arranged horizontally relative to the ground. "Horizontally arranged" refers to an arrangement in which the central axis of the shell and / or shell body extends along a direction parallel to the ground. A horizontal arrangement may avoid the need for heavy support structures. A horizontally arranged stove may also be easily accessible to an operator. In an alternative embodiment, the electric stove may be arranged vertically, which allows for a relatively space-saving installation. The term "horizontally" may also refer to a direction or plane parallel to the longitudinal direction.

[0029] In an embodiment, the shell body is configured to contain pressurized (reducing) gas, and the maximum pressure supported by the shell body is in the range of 0.0 bar(g) to 5.0 bar(g), preferably 1.5 bar(g) to 4.0 bar(g), and most preferably 3.6 bar(g). The width of the shell may be in a range defined depending on the pressure to be applied.

[0030] In embodiments, the shell body includes one of the following: carbon steel, a coating, a chromium-based alloy, or a mixture thereof. For example, the carbon steel may be a steel such as AISI 316L. The coating and chromium-based alloy may prevent hydrogen embrittlement and metal dusting that would otherwise occur in the presence of CO / CO or carbon compounds at high temperatures.

[0031] Further aspects and features of the invention emerge from the dependent claims, the accompanying drawings and the following description of embodiments. [Brief explanation of the drawings]

[0032] Embodiments of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: [Figure 1] 1 is a schematic perspective view of an embodiment of an electric heater; [Figure 2] 1 is a schematic transparent perspective view of an embodiment of an electric heater. [Figure 2A] FIG. 3 is an enlarged view of the cross section of FIG. 2. [Figure 3] 10 is a schematic diagram of a plurality of wires extending along a channel in a brick positioned opposite a gas outlet. FIG. [Figure 4] 1 is a schematic cross-sectional view of an embodiment of an electric heater with a centering element. DETAILED DESCRIPTION OF THE INVENTION

[0033] 1, there is shown one embodiment of an electric heater 10. The electric heater 10 comprises a hollow metal body made of steel, correspondingly a shell 12, extending along a longitudinal direction X. The electric heater 10 is placed horizontally relative to the ground, which may be referred to as a plane defined by the longitudinal direction X and the width direction Z.

[0034] Due to its horizontal arrangement, no internal support structure for the refractory is required. As a result, the risk of short circuits with the electrical connection module is avoided due to the horizontal arrangement due to the fact that a dedicated refractory support structure is not required. In contrast, a vertical arrangement (not shown) would require the refractory support structure and the electrical connection module to share the same space inside the stove, correspondingly the appliance, which would be prone to short circuits.

[0035] The electric stove 10 has a gas inlet 30 in fluid communication with a distribution ring 32, which includes a plurality of supply ports 34 configured to direct (reducing) gas to a first end 36 of the shell body 12, as best seen in FIG. 4. The support ports 34 are arranged concentrically with respect to a shell axis extending along the longitudinal direction X. A gas outlet 38, also extending along the shell axis, is arranged at a second end 40 facing the shell body 12.

[0036] As can be seen in FIGS. 2 and 4, a plurality of bricks 16 are arranged in adjacent layers 18, 20 extending along a longitudinal direction X.

[0037] The insulating lining 14 is provided on the inner surface of the shell body 12. The insulating lining 14 is formed by two layers of insulating linings 14.1 and 14.2. The first layer 14.1 of the insulating lining 14 is made of castable ceramic and is disposed on the inner surface of the steel shell 12. The second layer 14.2 of the insulating lining 14 is disposed on the first layer 14.1 and is formed of refractory bricks 14.2. As can be derived from FIG. 4, the specially shaped refractory lining Gu's A further layer is placed between the bricks 16 and the insulating lining 14. Gu is Also, some fireproof bricks Moth Fireproof lining Gu is The steel shell 12 is arranged and shaped so that a rectangular brick 16 can be inserted into the center of the steel shell 12. Gu is , supporting rectangular bricks 16. Figures 2 and 2A show the refractory lining within shell 12, which is shown transparently for the purpose of better understanding. Gu's It should be noted that the layers are merely illustrative. The embodiment shown in Figure 4 includes both layers 14.1 and 14.2 of the insulating lining 14, as well as the fire-resistant Lining Shows layers.

[0038] As shown in Figure 4, the specially shaped refractory lining Gu's Ren Moth 4, are not aligned with the layers of bricks 16 along the longitudinal direction X. However, in alternative embodiments, the layers of refractory bricks may be aligned with each other along the longitudinal direction X. Moth , it should be noted that the bricks 16 may be flush longitudinally with the layer of bricks 16.

[0039] As shown in FIG. 3 , each brick 16 includes a plurality of cavities 22 and semi-cavities 24 that extend linearly through the respective layer 20 along the longitudinal direction X. The brick 16 shown in FIG. 3 forms a portion of the outermost layer 20 opposite the gas outlet 38. The cavities 22 and semi-cavities 24 of different bricks 16 are aligned with the cavities 22 and semi-cavities 24 of bricks in adjacent layers 18 (not shown), such that the cavities 22 and semi-cavities 24 form channels 26 that extend through the different layers 18, 20, as shown in FIG. 4 . In other words, the bricks 16 form distinct linear paths that are parallel to each other along the longitudinal direction X. In addition, because the semi-cavities 24 are located in the edge regions of each brick 16, adjacent bricks 16 in the same layer 18, 20 may be aligned with each other such that the respective semi-cavities 24, 24 of adjacent bricks form an entire cavity 22, as also shown in FIG. 3 .

[0040] As shown in FIG. 3 , multiple heating wires 28 are guided through the cavities 22 and semi-cavities 24 of the brick 16. Each wire 28 has a diameter smaller than the diameter of the cavity 22 and corresponding channel 26. In other words, a single wire 28 is disposed within the cavity 22. Each electric heating wire 28 of the multiple heating wires has a U-shaped portion 42 disposed opposite the gas outlet 38. With this arrangement, the single wire 28 may cross two adjacently disposed channels 26. Thus, the wire 28 extends at least partially through the corresponding channel 26 and the corresponding cavities 24 and semi-cavities 26 that form the channel 26. When the electric stove is operating, the wire 28 dissipates a predetermined amount of heat energy while in contact with the (reducing) gas. This arrangement ensures rapid cooling of the heating wire 28, even in the wire portion disposed near or adjacent to the gas outlet.

[0041] FIG. 4 shows an embodiment of the electric heater 10 that includes a centering element 44. The centering element 44 has a structure similar to that of the brick 16, except for the geometric shape of the cavity (not shown), which is smaller compared to the brick cavity 22. This allows the wire 28 to be placed in a substantially central position within the channel 26. As a result, the heat dissipated by the wire 28 is uniformly distributed to the gas flowing around the wire 28. The centering elements 44 are spaced apart from one another by several layers of the brick 16. In other words, the positioning of the centering elements can be considered to represent a regular pattern within the matrix-like structure formed by the layers of the brick 16. Therefore, the centering elements 44 are spaced apart from one another by a predetermined distance.

[0042] Figure 4 also shows a schematic representation of the internal structure of the electric heater 10. The steel shell is designated by the reference numeral 12. Furthermore, the fireproof brick Moth Fireproof lining Gu is , and is disposed adjacent to the insulating lining 14. Moth, a cylindrical device, specially shaped to provide an arrangement of rectangular bricks 16 with corresponding cavities 22, 24 inside the cylindrical shell 12. It should be noted that the cylindrical shape allows for a more uniform distribution of stresses resulting from internal pressure.

[0043] An intermediate section 54 extends between the first end 36 and the second end 40. The intermediate section 54 includes different layers 18, 20 of the bricks 16.

[0044] Both layers 14.1 and 14.2 of the insulating lining 14 disposed below the surface of the shell 12 extend along the middle portion 54 and the second end portion 40. In the embodiment shown in FIG. 4, the ends 36, 40 do not require bricks 16 to guide the wires, and therefore the refractory lining Gu is The refractory lining simply extends along the middle portion 54 and supports the bricks 16. Gu is The ends 36, 40 are not required to have a heat insulating lining 14 and a refractory lining. Gu is , may include aluminum compound based materials.

[0045] In the embodiment shown in Figure 4, the first end 32 is not equipped with the complete insulating lining 14, but only with a first layer of insulating lining 14.1, due to the fact that the temperature is lower at the first end and less insulation is required.

[0046] As can be further deduced from FIG. 4 , the electric stove 10 also includes an electrical connection module 46 for providing electrical contacts to the electric heating wire 28. In the embodiment shown in FIG. 4 , the electrical connection module 46 is connected to a three-phase current-carrying cable connection having three cores 48, 50, and 52. The electrical connection module 46 is located within the first end 36 near the supply ports 34. By locating the connection module 46 at the first end 36, sufficient space is provided between the electrical connection module 46 and the different layers of bricks. In other words, the electrical connection module 46 is located outside the matrix-like structure formed by the layers of bricks 16. In this region, heat transfer is less effective compared to the channels within the matrix-like structure. The support ports 34 for introducing pressurized gas are arranged radially around the central longitudinal axis of the shell 12 (along the longitudinal direction X), thereby avoiding the appearance of prioritized / neglected regions that could lead to hot spots and / or low-temperature regions. On the other hand, the gas outlets 38 are arranged around the longitudinal axis.

[0047] Each of the electric heaters 10 shown in Figures 1 to 4 has a capacity of approximately 25 MW. t In the illustrated embodiment, the electric heater has a length of approximately 10 m and a diameter of 2 m. Features of the device, and correspondingly components of the electric heater, are configurable to allow for scaling of the power range.

[0048] The described embodiments are examples of the present invention. In the case of the embodiments, each of the described components of the respective embodiments should be considered independently of one another and represent individual features of the present invention that further develop the present invention independently of one another. Therefore, features should also be considered as elements of the present invention individually or in combinations other than those shown. Furthermore, the described embodiments can be supplemented by further features of the present invention that have already been described. Further features and embodiments of the present invention will occur to those skilled in the art in the context of this disclosure and the claims. [Explanation of symbols]

[0049] 10 Electric stove 12 shells 14. Insulating lining G 16 bricks 18 layers 20 layers 22 Cavity 24 semi-hollow 26 channels 28 heating wire 30 Gas inlet 32 Distribution Ring 34 Supply Port 36 First end 38 Gas outlet 40 second end 42 U-shaped part 44 Centering Elements 46 connection modules 48 cores 50 cores 52 cores 54 Middle section

Claims

1. An electric stove (10) for heating a reducing gas, comprising: a hollow metal shell body (12) extending along a longitudinal direction (X); a refractory lining disposed within the shell body (12); a plurality of bricks (16) arranged in adjacent layers (18, 20) extending along the longitudinal direction (X), each brick (16) including a plurality of cavities (22, 24) extending straight through the respective layer (18, 20) along the longitudinal direction (X), the cavities (22, 24) of adjacent layers (18, 20) being aligned with one another to thereby form a plurality of channels (26) having a diameter for conducting the reducing gas; The electric heater (10) The electric heater (10) further comprises a plurality of heating wires (28) for heating the reducing gas, each of the heating wires (28) having a diameter smaller than the diameter of one of the channels (26), and each of the heating wires (28) extending at least partially through at least one corresponding channel (26) of the plurality of channels such that a predetermined amount of heat is dissipated by each heating wire (28) to the reducing gas flowing around the heating wire when the electric heater (10) is operating.

2. 2. The electric stove (10) of claim 1, wherein at least two adjacent bricks (16) in a corresponding layer (18, 20) are each provided with a half-cavity (24), and the at least two adjacent bricks are aligned with each other such that the half-cavities (24) of the respective bricks form an entire cavity (22).

3. 2. The electric heater (10) of claim 1, wherein the diameter of said one channel (26) is between more than 1 and 5 times larger than the diameter of said heating wire (28).

4. 2. The electric heater (10) of claim 1, wherein a heat insulating lining (14) is disposed between a portion of the inner surface of the metal shell body and the refractory lining.

5. 5. The electric stove (10) according to claim 1, wherein the electric stove has a gas inlet (30) in fluid communication with a distribution ring (32), the distribution ring (32) having a plurality of supply ports (34) configured to direct the reducing gas to a first end (36) of the shell body (12), and the electric stove has a gas outlet (38) at a second end (40) of the shell body, the gas outlet (38) extending along the longitudinal direction (X).

6. 6. The electric heater (10) of claim 5, wherein each electric heating wire (28) of the plurality of heating wires has a U-shaped portion (42) positioned opposite or at the gas outlet (38).

7. 5. An electric heater (10) according to any one of claims 1 to 4, wherein the plurality of electric heating wires (28) are arranged in series and / or in parallel.

8. 5. The electric heater (10) according to any one of claims 1 to 4, wherein the electric heater (10) is configured to operate at low voltage with one of single-phase AC, three-phase AC, or DC.

9. 5. The electric stove (10) according to claim 1, further comprising centering elements (44), wherein the centering elements (44) forming part of the same channel (26) are aligned with one another along the longitudinal direction (X) in spaced layers, whereby the centering elements (44) are positioned at specific distances from one another.

10. 5. The electric stove (10) according to any one of claims 1 to 4, wherein the shell body (12) has a diameter in the range of 0.5 m to 4 m, and the shell body (12) has a length in the range of 5 m to 12 m.

11. 6. The electric stove (10) of claim 5, further comprising an electrical connection module (46) for providing electrical contacts to the electric heating wires (28), the electrical connection module (46) being positioned at the first end (36) spaced from the layers (18, 20) near the plurality of supply ports (34).

12. The electric heater (10) according to any one of claims 1 to 4, wherein the shell body (12) of the electric heater (10) is arranged horizontally with respect to the ground.

13. 5. The electric stove (10) according to any one of claims 1 to 4, wherein the shell body (12) is configured to contain pressurized reducing gas, and the maximum pressure supported by the shell body is in the range of 0.0 bar (g) to 5.0 bar (g).

14. 5. The electric stove (10) according to any one of claims 1 to 4, wherein the shell body (12) comprises one of the following: carbon steel, a coating, a chromium-based alloy, or a mixture thereof.

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