ZA200308040B

ZA200308040B - Cooling element for cooling a metallurgical furnace.

Info

Publication number: ZA200308040B
Application number: ZA200308040A
Authority: ZA
Inventors: Peter Heinrich; Luciano Ambrosi
Original assignee: Sms Demag Ag
Priority date: 2001-04-18
Filing date: 2003-10-16
Publication date: 2004-06-07
Also published as: WO2002084192A1; ES2242855T3; ATE295521T1; RU2281974C2; DE10119034A1; RU2003133461A; DE50203089D1; EP1381817A1; PT1381817E; CN1518657A; EP1381817B1; CN100342194C

Abstract

The invention relates to a cooling element for cooling a metallurgical furnace, in which the side of the furnace shell (113, 213, 313) that faces the interior of the furnace (Oi) is lined with fireproof material (114, 214, 314). Said element has a cooling part (2, 102, 202, 302) and a heating part that is cooled by thermal conduction (4, 104, 204, 304), and allows a protective layer against further clinker ("freeze-line") to form immediately in operating mode. The entire heating part consists only of a thin plate (5, 105, 205, 305), to which a separate cooling part (2, 102, 202, 302) is allocated on the cold side in the form of a pipe. The invention also relates to corresponding cooling systems and to a melting furnace.

Description

COOLING ELEMENT FOR COOLING A METALLURGICAL FURNACE

] The invention relates to a cooling element for cooling a metallurgical furnace, in particular the slag zone and/or the metal zone of this furnace, wherein the side ) of the furnace shell that faces the interior of the furnace is lined with refractory material, and wherein the cooling element comprises a cooling part through which coolant flows, with said cooling part comprising a coolant inlet and a coolant outlet, as well as a heating part that is cooled by thermal conduction, wherein in the installed state the heating part of the cooling element is arranged so as to be flush with the front of the refractory material which faces the interior of the furnace. Furthermore, the invention relates to a system for cooling a } metallurgical furnace which comprises at least one of these cooling elements, as well as a melting furnace comprising such a system.

Such metallurgical furnaces are used in the production of non-ferrous metals and raw iron. For this purpose, round or rectangular furnaces are used in which the required energy is fed in by way of self-baking electrodes of the Séderberg type. In many cases, the melting process starts by feeding in the energy by way of a freely burning arc which, after foamed slag has been formed, is immersed in said foamed slag. When the electrodes are immersed in the conductive liquid slag, the radiated energy is transferred completely to the metal bath as a result of resistance heating of the slag. In other cases, only part of the energy is fed to the metal bath by means of resistance heating. Energy transfer is achieved by way of small arcs which form between the electrode and the surrounding stock / column (brush arcing). In both cases there is a hot, liquid slag of approx. 1,400 to 1,700 °C which circulates in the furnace vessel due to thermal and magnetic effects. Thermal circulation is stimulated in particular by lifting forces due to changes in density as a result of cooling at the furnace wall.

Due to this circulation of the slag in the direction of the furnace wall — and also due to the chemical attack by the slag — the refractory material at the furnace wall, which refractory material forms the lining of the furnace, is subject to particularly severe wear. This wear only ceases when at a given heat load, the furnace wall which comprises refractory material is cooled to such an extent that a crust of solidified slag forms on its hot side, i.e. the side facing the interior of the furace. Such a crust is referred to as a freeze line. This solidified slag layer protects the refractory material against further slag erosion or slag corrosion and is thus a desirable protective layer. However, the higher the melting rate of the furnace and thus the heat flows, the thinner is the remaining wall thickness of the refractory material.

Higher melting-rate densities (kW/m? hearth area) occur in particular when in the case of existing furnaces the infeed of electrical power is to be increased in order to improve productivity, without, however, the hearth area being increased accordingly for reasons of cost-savings. This problem is not only encountered when upgrading existing furnaces, but also in the case of building new furnaces which are to have an increased power density. ; In order to generate and maintain this protective layer (freeze line) so that it is as thick as possible in spite of high heat flows, the conference report "Furnace

Cooling Design for Modern High-Intensity Pyrometallurgical Processes” of the

Copper 99-Cobre 99 International Conference, Vol. V, The Minerals, Metals &

Materials Society, 1999 by N. Voermann, F. Ham, J. Merry, R. Veenstra and K.

Hutchinson proposes the insertion of cooled copper bodies into the refractory furnace wall. Apart from so-called "fingers" and "plate coolers", in particular the use of so-called "waffle coolers” is proposed. Such waffle coolers are plate- shaped bodies, made with poured-in pipes, which on their hot side comprise dovetailed grooves and ribs. Refractory bricks are inserted into these grooves, or refractory ramming compound is rammed into said grooves. The cooling effect of the ribs in the waffle coolers results in the desired freeze line forming if there is direct contact between the refractory material and liquid slag. While / such waffle coolers advantageously assume a load-bearing function, they have the disadvantage of being very heavy and thus costly to produce.

Fingers and plate coolers are described by D. Tisdale, D. Briand, R. Sriram and

R. McMeekin, in "Upgrading Falconbridge’s No. 2 furnace crucible", published in "Challenges in Process Intensification”, Montreal PQ, Canada, Canadian

Institute of Mining, Metallurgy and Petroleum, 1996. The term "fingers" refers to copper pipes of round cross-section. It has however been proven difficult to place such pipes into the cuboid refractory bricks. This disadvantage does not apply to known plate coolers. However, said known plate coolers — as is also the case with fingers — have to be heavy and solid since their dimensions are determined by the diameter of the boreholes for the coolant, which boreholes are integrated in said plate coolers or fingers. This makes their production i a expensive. In their new state, fingers, plate coolers and waffle coolers do not penetrate the entire thickness of the refractory furnace wall, but instead they require additional masonry from their front facing the furnace. Furthermore, ) they are not connected to the outer wall of the furnace, the so-called furnace shell, in order to prevent jamming as a result of different thermal expansion ’ between the refractory brickwork and the furnace shell.

From E. Granberg, G. Carlsson, "Development of a device for cooling of the safety-zone in the electric arc furnace”, presented and published at the 3rd

European Electric Steel Congress, 2 - 4 October 1989, Bournemouth, cooling elements for the safety zone in electric arc furnaces for steel production are ; known whose effect is based on thermal conveyance from the hot side in the interior of the furnace to a cooling medium outside the furnace shell.

The cooling element made of cast copper comprises a water-cooled connector on which several solid plate coolers are arranged in a comb-like manner, with said plate coolers projecting into the interior of the furnace. Refractory material is arranged between the plate coolers. The connector is arranged outside the furnace shell. The thickness and centre distance of the plate coolers can be varied. This solution is associated with a disadvantage in that in an embodiment comprising thin plate coolers the load on the heat side becomes very substantial, combined with the danger of the copper oxidising which leads to a loss of thermal conductivity, while in an embodiment comprising thicker plate coolers, the cost of materials increases, and cooling is asymmetrical. i

It is thus the object of the invention to provide a cooling element and a cooling system for a metallurgical furnace, which cooling element and system avoids the above-mentioned disadvantages and comprises a hot side which in the operating state immediately forms a freeze line. Furthermore, a furnace is to be provided which when equipped with such a system provides excellent mechanical stability.

This object is met by a cooling element with the characteristics of claim 1, by cooling systems with the characteristics of claims 9 and 10, as well as by a furnace with the characteristics according to claims 16 and 17. Advantageous embodiments are disclosed in the subordinate claims.

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According to the invention it is proposed that the entire heating part be designed as a single plate and that on the cold side of the plate, i.e. on its side facing away from the interior of the furnace, a separate single cooling part ) which comprises a coolant inlet and a coolant outlet be associated with said plate.

In a way that is different from the designs of known solutions, in the design according to the invention, a cooling element is formed from a single plate which is associated with a separate cooling part which is independent of other cooling elements. In this way a favourable ratio of the surface of the heating part to the area of the cooling part is achieved, combined with favourable ; cooling properties. For this reason, in the operating state a protective layer or freeze line quickly forms immediately on the hot side of the cooling element, i.e. on the front of the refractory material facing the interior of the furnace and on the front of the plate.

According to a particularly preferred embodiment of the invention, the cooling part is a pipe, with that side of the plate which faces away from the interior of the furnace being non-detachably fixed to the pipe so as to be parallel to the longitudinal axis of the pipe. The joint is achieved by way of a full connection, preferably a weld connection, so as to ensure good thermal conduction.

Advantageously, the cooling element comprises a copper plate and a copper pipe, with these components being of a standard dimension which is readily available from stock. This will considerably reduce the cost of materials and above all the costs of processing. Overall, a versatile, economical and reliable cooling element is created in this way. It is also particularly advantageous if the components that are being used (plate, pipe), due to the way they are produced (rolling, extrusion) do not have a coarse-grained cast microstructure, but instead an evenly distributed fine-grained microstructure. This will ensure improved thermal conduction properties as well as a reduced tendency to crack formation or crack propagation.

Preferably, the plate is very thin, in the manner of sheet metal. The plate thickness comprises regions of between 10 and 40 mm, preferably between 20 and 40 mm.

In order to prevent warping of the thin plate or sheet as a result of different thermal expansion over the area of the plate, it is proposed that the plate or sheet comprise slots perpendicular to the longitudinal axis of the cooing pipe. i Due to this separation into individual independent plate strips, and also due to the reduced thickness, flexible adaptation to expansion movements in the ’ refractory material is achieved. This is associated with an additional special advantage in that it prevents the formation of insulating air gaps between the refractory material or refractory brickwork and the plate.

Preferably, the spacing between the slots is even. Spacing arrangements of approx. 100 to 400 mm at slot widths of 2-5 mm are recommended.

The proposed cooling systems comprise the following possible types: cooling system of type | with vertically arranged cooling elements, with the cooling part or pipe being arranged outside the furnace shell; cooling system of type Il with vertically arranged cooling elements, with the cooling part or pipe being arranged within the furnace shell; cooling system of type Ill with horizontally arranged cooling elements, with the cooling part or pipe being arranged outside the furnace shell; and cooling system of type IV with horizontally arranged cooling elements, with the cooling part or pipe being arranged within the furnace shell.

The cooling systems are designed depending on the melting-rate density and the distance between the electrode and the furnace wall, namely by selecting / the geometry of the plates and/or the spacing between the hot side and the cooling part and/or the spacing between the plates. When compared to known plate coolers, the plate of the heating part is thin. The spacing between the hot side and the cooling part, i.e. the pipe, is relatively small. Preferably, the geometry of the plate is rectangular. in such cooling systems, the vertical or horizontal spacing between the cooling elements and their adjacent cooling element is designed according to the multiple or a multiple of the height format or width format of refractory bricks which are used as the refractory material. In a horizontal arrangement this provides the advantage that the number of the cooling elements arranged one on top of the other can be flexibly matched to the height of the slag zone or the metal zone. In this way the refractory bricks do not require any cutting work, and installation expenditure can be kept low. ) It is proposed that preferably the cooling elements of a cooling system be connected in series on the water side, wherein the coolant outlet of a cooling element is connected to the coolant inlet of an adjacent cooling element, with said connections being established either by way of a rigid connection pipe or by way of flexible connection lines. The number of cooling elements which can be connected in series depends on the quality of the available cooling water and/or the maximum permissible temperature of the cooling water. ! According to the invention, the furnace design, in particular the furmace wall, must match the individual cooling systems and their characteristics. For a cooling system of type lll, a round or rectangular melting furnace is proposed, whose furnace shell, in the region of the cooling zone, is recessed in the direction of the interior of the furnace, comprising bulkhead plating to provide support for the now protruding upper region of the furnace part. Such a design of the fumace shell compensates for the weakening of its mechanical load- bearing capacity due to the horizontal slot arrangement at relatively short vertical spacing, which arrangement is necessary for the cooling elements.

In the case of a horizontal arrangement, the furnace shell comprises slots whose length corresponds to the horizontal extension of the cooling element.

The height of the slots is preferably selected such that the respective cooling / element can partake in the unavoidable thermal expansion of the refractory material, without being hindered in this movement by the upper or lower edge of the slot. Accordingly, the slots are relatively high.

When compared to the cooling system of type lll, the cooling system of type IV requires smaller apertures and thus smaller weaknesses in the fumace shell for coolant outlets and inlets of the cooling part or the pipe. This solution results in only a small decrease in the static load-bearing capacity of the furnace shell.

However, the load-bearing capacity can be increased still further in that the cooling elements are arranged one above the other so as to be offset in relation to each other.

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Cooling systems of type | and Il are worth considering in particular for round furnaces. The geometric shape of the plates, specifically their length, is preferably matched to the height of the slag zone. In type | where the plate of ) the heating part extends through the furnace shell and where the cooling part or the pipe is situated outside the furnace shell, a furnace shell whose stability has ‘ been weakened as a result of its vertical slots can be mechanically reinforced by means of ribs or rings so as to absorb the ring stress resulting from thermal expansion of the refractory material. It must be ensured that the vertical slots in the fumace shell allow unrestricted movement, in particular upward movement, of the cooling elements integrated in the refractory material. ; Further details and advantages of the invention are provided in the subordinate claims and in the following description, in which the embodiments of the invention, as shown in the figures, are explained in more detail. Apart from the combinations of characteristics mentioned above, characteristics on their own or in other combinations are also significant in the context of the invention. The drawing shows the following:

Fig. 1 a lateral view of a section of a cooling element proposed according to the invention, comprising a plate and a pipe;

Fig. 2 a cross-section of the cooling element according to Fig. 1 along the line A-A; : Fig. 3 a vertical section of a furnace wall with integrated cooling system of type lll and formed-in furnace shell;

Fig. 4 a horizontal section B-B of a furnace wall comprising a cooling system according to Fig. 3;

Fig. 5 a vertical section of a furnace wall with integrated cooling system of type IV;

Fig. 6 a horizontal section B-B of a furnace wall comprising a cooling system according to Fig. 5;

Fig. 7 a view of a cooling system of type IV, with the cooling elements, which are positioned one above the other, being arranged so as to be offset; and

Fig. 8 a vertical section of a furnace wall with integrated cooling system of type I.

Fig. 1 shows a section of a cooling element 1 which comprises a cooling part 2, through which coolant, for example water, flows, in the shape of a tube 3 with an interior diameter d; and a wall thickness d,, and comprises a heating part 4 which is only cooled by thermal conduction. The heating part 4, through which j cooling water does not flow, comprises a thin plate 5 of copper, which hereinafter is referred to as copper sheet. The pipe 3 is also made of copper; it is made to a standard dimension for copper pipe. The longitudinal side 6 on the cold side of the copper sheet is welded to the pipe jacket 7, parallel to the longitudinal axis of the pipe. Said copper sheet comprises slots 9, starting from the hot side 8, with said slots 9 in the embodiment shown extending as far as the weld seam 10. The heat from the interior of the furnace O; which heat reaches the hot side 8, is transferred by means of thermal conduction through the copper sheet to the pipe 3 and at this point to the coolant which flows through the pipe 3. The full connection, which makes possible unhindered thermal conveyance, between the copper sheet and the pipe 3, which in this embodiment is a weld seam 10, is also shown in Fig. 2. The copper sheet is relatively thin, preferably between 20 and 40 mm. Advantageously, copper

J sheet of a standard size is used. In combination with the slots 9, a flexible copper sheet results which makes for good thermal conveyance and at the same time can partake in the thermal expansion of the refractory material.

Fig. 3 shows an arrangement of a multitude of cooling elements 101 to form a cooling system. In the cooling system of type Ill (11) shown, the cooling elements 101 are arranged horizontally, i.e. the heating part 104, which is a copper sheet, is incorporated in the furnace wall 112 such that the plane of the plate extends perpendicularly to the longitudinal axis of the furnace.

The furnace wall 112 comprises the furnace shell 113 and refractory material 114 with which the side of the furnace facing towards the interior of the furnace

O; is lined. In the embodiment shown, the furnace shell 113 is made of masonry work which comprises refractory bricks 115 of a particular height He, with the transition to the refractory bricks 115 comprising refractory ramming compound 116. The individual cooling elements 101 are arranged in the cooling zone in ) such a way that the hot side 108 of the thin copperplate 105 or of the copper sheet, i.e. the front which is directly exposed to the furnace atmosphere, in its } installed state is flush with the front 117 of the refractory bricks 115, which front faces the interior of the furnace O,. In other words, no refractory material is necessary in front of the face of the copper plates.

In this embodiment, the cooling elements 101 are arranged one on top of the other, spaced apart by the distance taken up by two refractory bricks 115, ; wherein in each instance the masonry work is held to the furnace shell 113 by a brick anchor 118. Due to their design and their arrangement between the refractory bricks, the cooling elements are largely structurally self-supporting, which means that fastening elements can be saved.

The copper pipes 103 which are associated with each individual copper sheet and which form a cooling channel 119 are arranged outside the furnace shell 113. At the end of each pipe 103, pipe sections 120, 121 or transitions to coolant inlets 122 or coolant outlets 123 are provided; compare also Fig. 4.

Overall, as a result of the favourable ratio of the area of the heating part 104 to the area of the cooling part 102 of the individual cooling elements 101, a protective layer or freeze line 124 quickly forms along the hot part of the masonry work (only a section of the freeze line is shown). In this way, the

J residual wall strength of the refractory bricks 115 which are not affected by erosion is good.

Since the copper pipes 103 of the individual cooling elements 101 are situated outside the furnace shell 113, the furnace shell 113 comprises respective apertures 125 or slots which are somewhat longer than the lengths of the copper sheets. The height Hs of said apertures or slots must be sufficient to prevent the copper sheet from being restricted in the slot aperture 125 as a result of movement of the refractory bricks 115. In order to compensate for the weakness of the furnace shell 113 as a result of the aperture, said furnace shell 113 is curved inward (compare Fig. 3) in the region of the cooling zone formed by the cooling system 11, which region can approximately correspond to the slag zone. Forces from higher-positioned components of the fumace structure ol

126, which forces act on the furnace shell 113, are absorbed by means of bulkhead plating 127 and/or transferred downward. ) The metal zone which joins underneath the slag zone can also comprise such a cooling system 11 or - as shown - can comprise a cascade cooling system 128 ) which acts from the outside on the furnace shell 113. To this effect, the side of the furnace shell 113 which faces away from the interior of the furnace is encased such that there is a gap 129. Cooling water is fed into the gap 129 by means of a feed pipe 130 so that it cascades down along the outside of the furnace shell 113. ; The arrangement of the above-mentioned bulkhead plating 127 is particularly evident in Fig. 4 which shows a horizontal section, along the line B-B, of the cooling system 11 in the furnace wall 112 of a melting furnace. The length of the copper pipes 103 can be between one metre and several metres, but also less than one metre; it approximately corresponds to the length of the copper sheet.

The cooling system of type Ill (11) described above, which comprises copper pipes situated outside the furnace shell, is used in particular in melting fumaces which are lined with refractory material which reacts with water at high temperature, such as for example magnesium oxide. If an arrangement of pipes that carry cooling water is acceptable within the furnace shell, a cooling element system of type IV (12) is used, as shown in more detail in Figs 5 and 6. Fig. 5 } shows a vertical section of a fumace wall 212, while Fig. 6 shows a horizontal section.

The copper pipes 203 with the cooling channel 219 of the cooling elements 201 are arranged within the refractory ramming compound 216 which is located between the furnace shell 213 and the refractory bricks 215. As is the case in the cooling system of type lll (11), the thin plates 205 or copper sheets are arranged between the individual refractory bricks 215. The furnace shell 213 comprises apertures 225 to accommodate the two pipe sections 220, 221 for the respective coolant inlet 222 and the respective coolant outlet 223 of each copper pipe 203. Although in this cooling system 12 the furnace shell 213 is weakened to a far lesser extent, bulkhead plating 227 for increasing the stability

S11 - can be provided (compare Fig. 6), which bulkhead plating 227 extends within the furnace vessel 230 on the cold side of the furnace shell 213. ) In the cooling system of type IV (12), an increase in stability is achieved by arranging the layers of cooling elements 201 so that they are offset one above ’ the other, as shown in Fig. 7. Fig. 7 shows a cooling system of type IV (12), viewed from the cold side of the furnace shell, comprising internally arranged copper pipes 2083 of horizontally arranged cooling elements 201, arranged one on top of the other, of a first, second, third and fourth level. By way of a mutual feed channel 231, cooling water enters through the inlet pipe sections 220, which protrude through the respective apertures in the furnace shell, into the ; copper pipes 203 of the cooling elements 201 of the first or lowermost level, and leaves again through the respective outlet pipe sections 221. However, in the embodiment shown, the cooling water does not exit immediately, but instead is conveyed, by way of internal connection pipes 232 which are also embedded in the refractory ramming compound, to the inlet pipe sections 220 of the copper pipe 203 of the cooling elements 201 of the next-higher level.

This conveying of cooling water is continued until the cooling water has passed through the copper pipes 203 of the cooling elements 201 of the fourth or uppermost level, and the cooling water, by way of outlet pipe sections 221 and cooling water outlets 223 flows into a mutual return channel from which said cooling water is conveyed into a cooling water recooling system (not shown).

Cooling systems of types Ill (11) and (IV (12) are used in particular in the case / of rectangular furnaces, while cooling systems of types | and ll are used in particular in the case of round furnaces. Fig. 8 shows a vertical section of cooling elements of a system of type | (13). In this type of cooling system, the cooling elements 301 are arranged in the furnace wall such that the plane of the plates 305 or the longitudinal axis of the copper pipes 303 extends parallel to the longitudinal axis of the furnace. The cooling part 302 or the copper pipe 303 of each cooling element 301 is situated outside the furnace shell 313.

Preferably, the length of the copper sheets corresponds to the height of the slag zone. The slots of the copper sheet are designated 309. For the purpose of installing the cooling elements 301, the furnace shell 313 comprises long narrow apertures 325 or slots which extend in vertical direction. Preferably, the furnace shell 313 is reinforced by ribs or rings 335a, b.

Claims

1. A cooling element for cooling a metallurgical furnace, wherein the side of the furnace shell (113, 213, 313) that faces the interior of the furnace (O;) is lined with refractory material (114, 214, 314), comprising a cooling part (2, 102, 202, 302) through which coolant flows, with said i cooling part (2, 102, 202, 302) comprising a coolant inlet (122, 222, 322) and a coolant outlet (123, 223, 323), as well as a heating part (4, 104, 204, 304) that is cooled by thermal conduction, wherein in the installed state the heating part of the cooling element is arranged so as to be flush with the front (117) of the refractory material (114, 214, 314) which faces the interior of the furnace (O)), characterised in that the entire heating part is designed as a plate (5, 105, 205, 305) and that on the cold side, a separate cooling part (2, 102, 202, 302) is associated with this plate (5, 105, 205, 305).

2. The cooling element according to claim 1, characterised in that the cooling part is a pipe (3, 103, 203, 303) and that the side of the plate (5, 105, 205, 305) which faces away from the interior of the furnace (Oy) is non-detachably fixed to the pipe (3, 103, 203, 303) so as to be parallel to the longitudinal axis of the pipe.

3. The cooling element according to claim 2, characterised in that

} _ the plate (5, 105, 205, 305) is connected to the pipe (3, 103, 203, 303) with a full connection.

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4. The cooling element according to any one of claims 1 to 3, ) characterised in that the thickness of the plate (5, 105, 205, 305) is between 10 and 40 mm, preferably between 20 and 40 mm.

5. The cooling element according to any one of claims 2 to 4, characterised in that the plate (5, 105, 205, 305) comprises slots (9, 309), which extend perpendicularly to the longitudinal axis of the pipe (3, 103, 203, 303), which slots, starting from the side of the plate that is not connected to the pipe, have been formed in the plate in the direction of the pipe.

6. The cooling element according to claim 5, characterised in that the slots (9, 309) are evenly spaced apart and extend up to the pipe (3, ! 103, 203, 303).

7. The cooling element according to any one of claims 2 to 6, characterised in that the length of the pipe (3, 103, 203, 303) is between one metre and several metres.

8. The cooling element according to any one of claims 1 to 7, characterised in that

: C5 both the plate (5, 105, 205, 305) constituting the heating part, and the pipe (3, 103, 203, 303) constituting the cooling part are made from copper or some other thermoconducting material.

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9. A system for cooling a metallurgical furnace comprising at least one : cooling element according to any one of claims 1 to 8, wherein the side of the furnace shell (113, 213) that faces the interior of the furnace (Oy) is lined with refractory material (114, 214,), and wherein the respective cooling element comprises a cooling part (102, 202) through which coolant flows, with said cooling part (102, 202) comprising ! a coolant inlet (122, 222) and a coolant outlet (123, 223), as well as a heating part (104, 204) that is cooled by thermal conduction, and wherein in the installed state the heating part of the cooling element is arranged SO as to be flush with the front (117) of the refractory material (114, 214) which faces the interior of the furnace, characterised in that the heating part, which is designed as a single plate (105, 205), is installed in the furnace wall (112) that is constituted by the furnace shell (113, 213) and the refractory material (114, 214) such that the plane of the plate extends perpendicularly in relation to the longitudinal axis of the furnace (horizontal arrangement).

10. The system for cooling a metallurgical furnace comprising at least one cooling element according to any one of claims 1 to 8, wherein the side of the furnace shell (313) that faces the interior of the furnace (Oy) is lined with refractory material (314), and wherein the respective cooling element comprises a cooling part (302) through which coolant flows, with said cooling part (302) comprising a coolant inlet (822) and a coolant outlet (323), as well as a heating part (304) that is cooled by thermal conduction, and wherein in the installed state the heating part of the cooling element is arranged so as to be flush with the front of the refractory material which faces the interior of the furnace,

i Co. characterised in that the heating part, which is designed as a single plate (305), is installed in : the furnace wall that is constituted by the furnace shell (314) and the refractory material (314) such that the plane of the plate extends parallel ) in relation to the longitudinal axis of the furnace (vertical arrangement).

11. The system according to claim 9 or 10, characterised in that ; the cooling part (202) of the respective cooling element (201) through which cooling part (202) coolant flows is arranged on the side of the furnace shell (213) which faces the interior of the furnace (0).

12. The system according to claim 9 or 10, characterised in that the cooling part (102, 302) through which coolant flows is arranged on the side of the furnace shell (113, 313) which faces away from the interior of the furnace (Oy).

13. The system according to any one of claims 9 to 12, characterised in that the geometry of the plates (105, 205, 305) and/or the spacing between the hot side (108) and the cooling part (102) and/or the spacing between the plates (105, 205, 305) of the cooling elements in relation to each other are/is designed according to the melting-rate density.

14. The system according to any one of claims 9 to 13, characterised in that

: Ce the spacing between the plates (105, 205, 305) and adjacent cooling elements (101, 201, 301) is dimensioned according to the multiple or a multiple of the height format (Hr) or width format of refractory bricks ) (115, 215) which are used as the refractory material. ; 15. The system according to any one of claims 9 to 14, characterised in that the coolant outlet of a cooling element is connected to the coolant inlet of an adjacent cooling element (201).

16. A melting furnace comprising a system according to claims 9 and 12 for cooling the slag zone and/or metal zone with at least one cooling element according to any one of claims 1 to 8, characterised in that in the case of a horizontal arrangement of several layers of cooling elements (101) which constitute a cooling zone, and in an arrangement of the cooling part (102) through which coolant flows, on the side of the furnace shell (113) which faces away from the interior of the furnace (Oy), the furnace shell (113) in the region of this cooling zone is recessed in the direction of the interior of the furnace (O;), and in that said furnace s shell (113) is supported above the cooling zone by means of a metal plate structure, in particular by means of bulkhead plating (127), for transferring vertical forces.

17. The melting furnace comprising a system according to claims 10 and 12 for cooling the slag zone and/or metal zone with at least one cooling element according to any one of claims 1 to 8, characterised in that in the case of a vertical arrangement of several cooling elements (301) which constitute a cooling zone, and in an arrangement of the cooling part (302) through which coolant flows, on the side of the furnace shell i Ce

(313) which faces away from the interior of the furnace (Oy), the furnace shell (313) is reinforced by means of ribs (335a, b) or rings.

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18. The melting furnace according to claim 16 or 17,

) characterised by a round fumace (Og) or a rectangular furnace (Oge) for producing non- ferrous metal or raw iron, or by an arc furnace for the production of steel.

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