WO2025099777A1

WO2025099777A1 - Cooling apparatus for a metallurgical furnace and corresponding furnace

Info

Publication number: WO2025099777A1
Application number: PCT/IT2024/050220
Authority: WO
Inventors: Massimo VARUTTI; Marco Ansoldi; Stefano Terlicher; Luca BLARZINO
Original assignee: Danieli and C Officine Meccaniche SpA
Current assignee: Danieli and C Officine Meccaniche SpA
Priority date: 2023-11-09
Filing date: 2024-10-30
Publication date: 2025-05-15
Anticipated expiration: 2026-05-09
Also published as: IT202300023610A1

Abstract

Cooling apparatus (10) for a metallurgical furnace (100), in which at least one container (110) is provided with at least one perimeter wall (130), the apparatus (10) comprising at least one cooling module (11) associated at least with the perimeter wall (130) and provided inside with a plurality of nozzles (15) arranged to spray the coolant fluid with which they are fed against a first element (200) of the perimeter wall (130) directly facing the melting chamber (160); each of said nozzles (15) is arranged to define a spraying cone (16) of the coolant fluid against the first element (200) with a certain angle (a) of amplitude and is positioned at a first distance (DI) from an adjacent nozzle (15), at least the ratio between the angle (a) and the first distance (DI) is such that each spraying cone (16) defines a spray area (17) on the first element (200) and an intersection portion (19) with the spraying cone (16) of the adjacent nozzle (15).

Description

“COOLING APPARATUS FOR A METALLURGICAL FURNACE AND CORRESPONDING FURNACE”

FIELD OF THE INVENTION

The present invention concerns a cooling apparatus for a metallurgical furnace, such as for example an electric arc furnace (EAF), and the furnace itself. More specifically, the present invention concens a cooling apparatus integrated with the walls, and possibly with the vault, of the metallurgical furnace. This apparatus is formed by a containing structure inside which nozzles, fed with a coolant fluid, are installed which, through spraying, define a certain heat exchange, keeping the temperature of the wall that faces toward the inside of the metallurgical furnace within adequate limits.

BACKGROUND OF THE INVENTION

A traditional metallurgical furnace, such as a known electric arc furnace for example, has a perimeter wall and a vault, both made of refractory material, on which cooling apparatuses are installed, provided to perform a desired heat exchange.

Generally, known cooling apparatuses are fed with a coolant fluid, normally water, in turn fed by a suitable feeding system.

The cooling apparatuses can comprise coils of pipes inside which the coolant fluid flows, or they can have one or more box-shaped elements to house a plurality of nozzles inside them, which are capable of spraying the coolant fluid against a surface of the furnace’s wall, the latter directly facing the furnace’s melting chamber.

In both cases, over time a certain amount of slag adheres to the side facing toward the melting chamber, this slag acting as an insulator thanks to its low thermal conductivity, protecting the cooling apparatus and increasing the efficiency of the process that is taking place inside the furnace.

The solution with the pipe coils, however effective in terms of heat exchange, requires a coolant fluid pressure higher than atmospheric pressure inside the circuit, thus proving to be unattractive for some markets because, in addition to the need to provide accessory pressure pumping equipment, in the event of holes in the pipes, in extreme conditions any leakages could result in hazardous situations; therefore there is a preference for solutions that work at atmospheric pressures, such as solutions with nozzles for example.

In fact, the solution with nozzles provides that the coolant fluid is fed at low pressure, approximately around atmospheric pressure, so even in the event of fluid leakages, the risks are more controlled than in the case of leakages from the coil panels where the fluid is at high pressure.

In order to guarantee this type of solution operates optimally, it is necessary for the coolant fluid to be sprayed substantially uniformly against the walls of the panels, in order to obtain a removal of the heat above a desired minimum value. However, since the nozzles are housed inside the box-shaped elements, and therefore not directly in view, in the event of malfunction, or obstruction, of one or more nozzles, a localized cooling loss can occur in one or more areas, not immediately identifiable.

Known solutions are disclosed for example in document EP0393970B2, which concerns the cooling of hot bodies, in document JPHO755363A, which concerns pipes for high-temperature gasses, in document EP00445I2AI, which concerns a method and an apparatus for cooling parts of receptacles of a metallurgical furnace, in particular of an electric arc furnace, in document US5601427A, which concerns a furnace and a method for melting waste, and in document JPH0395391 A, which concerns a cover for a furnace.

To date, there is no immediate way to detect a possible loss of cooling, to the detriment of the operating conditions of the furnace and its components, as this may also compromise some operating components of the vat, or of the furnace’s vault. There is therefore the need to perfect a cooling apparatus for a metallurgical furnace that can overcome at least one of the disadvantages of the state of the art.

To do this, it is necessary to solve the technical problem of improving the cooling reliability and efficiency of a cooling apparatus for a metallurgical furnace that uses nozzles to cool the panels that form at least the lateral wall of the furnace, even in the event of malfunctions or obstructions of one or more nozzles.

One purpose of the present invention is to provide a low-pressure cooling apparatus for a metallurgical furnace that, even in the event of malfunctions or obstructions of one or more nozzles, is capable of guaranteeing a cooling efficiency above a certain minimum value.

Another purpose of the present invention is to provide a cooling apparatus for a metallurgical furnace in which the heat extraction can be managed independently depending on the zone of the furnace being cooled. Another purpose of the present invention is to provide a cooling apparatus for a metallurgical furnace in which each nozzle or group of nozzles can be monitored to verify whether the cooling is occurring appropriately.

Another purpose of the present invention is to provide a metallurgical furnace, in particular an electric arc furnace, equipped with the aforementioned cooling apparatus with nozzles.

The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION The present invention is set forth and characterized in the independent claims. The dependent claims describe other characteristics of the present invention or variants to the main inventive idea.

In accordance with the above purposes and to resolve the technical problem described above in a new and original way, also achieving considerable advantages compared to the state of the prior art, a cooling apparatus according to the present invention is applied to a metallurgical furnace, of the type provided at east with a container having, in turn, at least one perimeter wall that internally defines a melting chamber, in which a metal charge can be selectively inserted for subsequent melting. The cooling apparatus according to the present invention comprises at least one cooling module, which is associated with the perimeter wall and is provided with a plurality of nozzles inside it.

By associated with the perimeter wall we mean both as an external element, that is, attached to and in operational cooperation with the wall, and also as an integral part of the wall, for example to define an operational hollow space in which the nozzles operate.

According to the present invention, it is not excluded that a single cooling module can be provided that affects the entire perimeter wall, and also, alternatively, that several modules coupled together can be provided.

The nozzles are fed with a coolant fluid and are arranged to spray the latter against a first element of the perimeter wall, which is directly facing the melting chamber, so that each nozzle operates a localized cooling of this first element. In accordance with one aspect of the present invention, each of the nozzles is arranged to define a spraying cone having a certain angle of amplitude a and is positioned at a first distance DI from an adjacent nozzle. The ratio between the angle of amplitude a and the first distance DI can be chosen so that each spraying cone defines a spray area on the first element and an intersection, or partial overlap, portion with a spray area defined by the adjacent nozzle.

The at least one cooling module comprises feeding lines of the coolant fluid, to which the nozzles are hydraulically connected, the feeding lines being arranged so as to define a plurality of rows, or columns, of nozzles and being hydraulically connected to at least one coolant fluid feeding manifold, the manifold being annular and positioned, during use, along the perimeter wall.

In this way, according to the present invention, there is a distribution substantially over the entire portion of the first element affected by the action of the cooling module, thus improving the reliability and efficiency of the cooling performed. Furthermore, with the present solution, by guaranteeing a dense spraying density on the first element, even in the event of malfunction or obstruction of one or more nozzles, it is possible to achieve cooling with an efficiency above a certain minimum value. In fact, in these cases, the interference portions allow to at least partly compensate for the lack of cooling of one or more adjacent nozzles, so as to limit the increase in temperatures to a minimum and, consequently, the possibility of negatively interfering in the melting steps, or operationally compromising some components of the furnace.

Moreover, the present solution guarantees a high effectiveness and speed of distribution of the coolant fluid to the nozzles, which allows to further increase the spraying density and uniformity.

According to another aspect of the invention, each feeding line can be selectively isolated from the other feeding lines by means of corresponding closing valves, so as to possibly feed single rows and/or columns of nozzles, or groups of rows and/or columns of nozzles, with coolant fluid.

In this way it is possible, if necessary, to select a differentiated cooling in different zones of the furnace, or to cool only certain zones of the furnace.

According to another aspect of the invention, columns of nozzles located in succession are separated by a first distance, and rows of nozzles located in succession are separated by a second distance, the first distance and the second distance being such as to allow high intersection portions, in which three or more spray areas overlap.

According to another aspect of the invention, the first distance is comprised between 300 mm and 400 mm and the second distance is comprised between 350 mm and 500 mm. These values allow for considerable portions of high intersection, further increasing the cooling uniformity and efficacy.

According to another aspect of the invention, the feeding lines comprise lateral branches which carry the coolant fluid to the nozzles. Advantageously, the ratio between the angle of amplitude a and the first distance DI is chosen so as to guarantee that the intersection portion between two adjacent spraying cones has a surface area comprised between approximately 5% and approximately 65% of each spray area. Advantageously, this percentage is approximately 30%. The choice of this specific percentage range, together with the other interference portions that are defined between all the spray areas, further guarantees effective and uniform cooling of the first element of the perimeter wall.

In this way, the possibility of carrying out an effective and desired cooling, substantially of the main critical areas of the melting chamber, is guaranteed, thus further improving the reliability and efficiency of the cooling carried out.

In accordance with some embodiments of the present invention, in which the metallurgical furnace comprises a closing vault to selectively close the melting chamber from above, the cooling module can be associated with the closing vault, together with, or as an alternative to, the perimeter wall, and each of its nozzles is arranged to define a spraying cone of the coolant fluid against the second element; also in this case, there is defined a spray area and an intersection portion with the spray area of the spraying cone of an adjacent nozzle.

In accordance with another aspect of the present invention, each of the nozzles is positioned at a second distance D2 from the first element, comprised between 150 mm and 300 mm.

In this advantageous solution of the present invention, the nozzles all come to be substantially at the same distance from the first element, thus being able to guarantee a uniformity of cooling action on the first element itself, to the advantage of the quality and repeatability over time of the cooling action. Furthermore, the second distance D2, if modified, can also influence the amplitude of the spray area and, therefore, the intersection portions that come to be defined between two adjacent spray areas, increasing the possible design choices as a function of the metallurgical furnace’s specific operating conditions.

In some variants, one or more parameters that define the spray area can be selectively, and possibly individually, modified to achieve different operating conditions, for example, in order to compensate for a nozzle malfunction, or to punctually intensify the cooling action in a desired position of the perimeter wall, or other.

In accordance with another aspect of the present invention, the nozzles of a same cooling module are fed individually or in groups by one or more coolant fluid feeding lines, and each group comprises a number of nozzles comprised between five and eleven, which can also be different from one cooling module to a possible other.

For example, a plurality of rows or columns of nozzles can be arranged within each individual cooling module, disposed substantially parallel to each other with a matrix, quincunx, or other layout. As mentioned, each row or column can be fed individually or in groups, by means of specific feeding lines, so as to define, within the same cooling module, different cooling zones of the first or second element.

In this way, it is possible to modify, improve or focus, in certain sectors, the cooling of the perimeter wall or of the closing vault, for example as a function of the specific melting steps or of temperature values detected by thermal sensors.

The solution according to the present invention therefore allows to carry out a heat extraction that is managed independently depending on the zone of the furnace being cooled.

In accordance with another aspect of the present invention, there can be provided a single cooling module disposed for the partial or total coverage of the perimeter wall, or of the vault; equally, a plurality of cooling modules can be provided, for example comprised between two and seven, advantageously five, deliberately distributed on the perimeter wall; similarly, the closing vault can be made in one or more connected sections. Advantageously, each cooling module can be fed individually and with different operating conditions, or conditions that can be differentiated from the others, and comprises a circuit for the collection and evacuation of the waste coolant fluid.

In accordance with another aspect of the present invention, the apparatus comprises at least one temperature detection element, arranged to detect the cooling temperature of the perimeter wall. Preferably, the installation points of the detection elements are those with the greatest exposure to the electrodes, therefore those that define the shortest distance in a straight line between the cooling module and the electrode.

In this way, each cooling module or group of cooling modules can be monitored to verify whether the cooling is occurring properly.

Advantageously, a command and control unit can also be provided, which is connected to the detection elements so as to compare the data detected by each detection element, for example, with a system datum, and give this comparison to an operator or to a computer programmed in order to keep the operating parameters of the metallurgical furnace within certain limits.

In accordance with another aspect, the present invention also concerns a metallurgical furnace provided with at least one container having at least one perimeter wall which internally defines a melting chamber.

According to the invention, with the metallurgical furnace there is associated a cooling apparatus provided at least with a cooling module, which is associated with the perimeter wall.

Inside it, the cooling module is provided with a plurality of nozzles fed with a coolant fluid and arranged to spray the coolant fluid against a first element of the perimeter wall, which directly faces the melting chamber. Always according to the solution according to the present invention, each of the nozzles is arranged to define a spraying cone having a certain angle of amplitude a and is positioned at a first distance DI from an adjacent nozzle. In this way, the ratio between the angle of amplitude a and at least the first distance D 1 is such that each spraying cone defines a spray area on the first element and an intersection portion with a spray area of the spraying cone of the adjacent nozzle. Moreover, the at least one cooling module comprises feeding lines of the coolant fluid to which the nozzles are hydraulically connected, the feeding lines being arranged so as to define a plurality of rows, or columns, of nozzles and being hydraulically connected to at least one coolant fluid feeding manifold, the manifold being annular and positioned, during use, along the perimeter wall.

According to another aspect of the invention, the furnace comprises a single cooling module integrated into a hollow space of the perimeter wall, the hollow space being defined, at least on one side, by the first element.

According to another aspect of the invention, the manifold is disposed circularly inside the hollow space and is open toward the outside of the perimeter wall, by means of at least one pipe union.

According to another aspect of the invention, one or more inspection doors are provided on the perimeter wall of the furnace’s container to allow the inspection of the cooling module/s, or parts thereof.

DESCRIPTION OF THE DRAWINGS

These and other aspects, characteristics and advantages of the present invention will become apparent from the following description of an embodiment, given as a non-restrictive example with reference to the attached drawings wherein:

- fig. 1 is a schematic representation of a metallurgical furnace to which a cooling apparatus according to the present invention is applied;

- fig. 2 is a partial perspective view of the furnace of fig. 1 ;

- fig. 3 is the enlarged detail III of fig. 1 ; - fig. 4 is a view from IV of fig. 1 ;

- fig. 5 schematically shows an operating condition of the cooling apparatus of fig. 1 ;

- fig. 6 schematically shows a first operating alternative of fig. 5; and

- fig. 7 schematically shows a second operating alternative of fig. 5. We must clarify that the phraseology and terminology used in the present description, as well as the figures in the attached drawings also in relation as to how described, have the sole function of better illustrating and explaining the present invention, their purpose being to provide a non-limiting example of the invention itself, since the scope of protection is defined by the claims.

To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one embodiment can be conveniently combined or incorporated into other embodiments without further clarifications.

DESCRIPTION OF SOME EMBODIMENTS OF THE PRESENT INVENTION

With reference to fig. 1, a cooling apparatus 10 according to the present invention is applied for cooling, or at least for carrying out a cooling heat exchange, of desired internal areas of a metallurgical furnace 100, in this specific case an electric arc furnace (EAF), in particular during the melting steps of the metal material, in order both to reduce the wear of the parts of the furnace 100, and also to increase the efficiency of the melting process that is taking place inside the furnace 100.

Briefly, the furnace 100 comprises a container 110 with a substantially cylindrical shape and having a lower vat 120, a perimeter wall 130 disposed above the vat 120 and open at the top, and a vault 150 of the selectively openable type placed so as to close the perimeter wall 130, through which the electrodes 300 can at least partly pass. The cross-section of the container 110 can have shapes other than circular, for example oval. Furthermore, the container 110 internally defines, as a whole, a melting chamber 160 in which a metal charge M can be selectively inserted for the subsequent melting, and in which the combustion fumes deriving from the melting process circulate.

The vat 120 has a concave bottom, which in the wear zone is made of refractory material, capable of withstanding high temperatures, above l,600°C, and the melting of the metal charge M takes place inside it. The vat 120, as in the prior art, is normally provided with a tapping hole through which the molten and scorified steel can be selectively tapped.

The perimeter wall 130 comprises, or consists of, a first element, or panel 200, in this specific case substantially cylindrical, and which directly faces the melting chamber 160 with an internal surface 210 thereof. An external surface 220 is provided opposite the latter. For a simple description, here and hereafter in the description we refer to a generic panel 200, although it is not excluded that the latter can be formed by a set of panels suitably connected to each other in order to define the perimeter wall 130.

The vault 150 comprises, or consists of, a second element, or panel 250 having an internal surface 260 directly facing the melting chamber 160, and an external surface 270 opposite the internal surface 260, which can also be realized with one or more panels connected to each other.

In the embodiment shown in the attached drawings, the apparatus 10 according to the present invention comprises a single cooling module 11, which is integrated into a hollow space 12 of the perimeter wall 130 defined, at least on one side, by the panel 200. In the solution shown, it is therefore provided that the perimeter wall

130 itself is at least partly defined by the cooling module 11.

Also within the scope of the present invention is the solution in which a plurality of cooling modules 11 are provided, for example in number between two and seven, advantageously five, deliberately distributed on the perimeter wall 130. It is not excluded that the single, or the plurality, of cooling modules 11 can be applied externally to the perimeter wall 130, although always in direct cooperation with the panel 200.

Advantageously, one or more inspection doors 13 are provided on the perimeter wall 130, provided to allow operators a direct inspection of the cooling module(s) 11 , or parts thereof, for example in case of operational maneuvering, maintenance, or other.

As shown only schematically in fig. 1 , the cooling module(s) 11 can also be effectively associated with the vault 150, in direct cooperation with the panel 250, and with the same spraying operating characteristics described with regards to the application to the perimeter wall 130.

The cooling module 11 comprises a plurality of nozzles 15, fed with a low- pressure coolant fluid, and arranged to spray this coolant fluid directly against the external surface 220 of the panel 200.

As shown in figs. 3 and 4, each nozzle 15 is arranged to define a spraying cone 16 having a certain angle a of amplitude, for example comprised between 90° and

150°, advantageously of about 120°, and is positioned at a first distance DI, for example comprised between 300 mm and 400 mm, advantageously between 320 mm and 350 mm, from an adjacent nozzle 15. In the solution shown in the attached drawings, each nozzle 15 is also disposed at a second distance D2, for example comprised between 150 mm and 300 mm, advantageously between 190 mm and 210 mm, from the panel 200 and at a distance D3, for example comprised between 350 mm and 500 mm, advantageously between 420 mm and 460 mm, from an adjacent upper or lower row of nozzles 15.

According to the invention, at least the ratio between the angle a and the first distance DI is such that each spraying cone 16 defines a spray area 17 (figs. 4, 5 and 6) on the external surface 220 of the panel 200, and an intersection portion 19 with a spray area 17 defined by a spraying cone 16 of an adjacent nozzle 15.

Advantageously, each intersection portion 19 has a surface area comprised at least between about 5% and about 65%, advantageously 30%, of each spray area 17.

The cooling module 11 also comprises feeding lines 20 of the coolant fluid, to which the nozzles 15 are hydraulically connected.

In particular, the cooling module 11 can comprise a variable number of both feeding lines 20 and also of nozzles 15, for example comprised between five and eleven. In a solution in which a plurality of cooling modules 11 are provided, the number of nozzles for each cooling module 11 can also differ from one cooling module 11 to another, as a function of the thermal extraction arrangements provided. Each feeding line 20 can feed one or more pairs of nozzles 15 located on opposite sides thereof, see fig. 2 or fig. 4. The feeding line 20 therefore substantially comprises lateral branches 28 (fig. 4) which carry the coolant fluid to the nozzles 15 and allow, for example, to position the nozzles 15 in desired cooling zones of the furnace and to distribute the coolant fluid effectively.

In the solution shown in the attached drawings, each feeding line 20 is, in turn, fed by at least one substantially annular manifold 21 positioned, during use, along the perimeter wall 130. The feeding lines 20 are therefore hydraulically connected to the manifold 21. The manifold 21 is, in particular, disposed circularly inside the hollow space 12 and is open toward the outside of the perimeter wall 130, by means of a pipe union 22. The latter is hydraulically connected to feeding means of the coolant fluid, of a substantially known type and not shown in the attached drawings.

Furthermore, each feeding line 20 is able to be selectively isolated from the other feeding lines 20 by means of corresponding closing valves 23, by means of which the flow rate of the coolant fluid can be regulated, and even interrupted. Advantageously, the inspection doors 13 are provided in correspondence with the closing valves 23, so as to optimize the manipulation and maintenance operations thereof.

As schematically shown in figs. 5 and 6, inside the single cooling module 11 the feeding lines 20 can be arranged to define a plurality of rows X, or columns Y, of nozzles 15, the latter being disposed substantially parallel to each other with a matrix (fig. 5), or quincunx (fig. 6), or other layout. The distance DI defines the space between two parallel columns Y located in succession, while the distance D3 defines the space between two parallel rows X located in succession.

For example, as shown in fig. 7, the distances DI and D3 between the nozzles 15 can be chosen so as to define high intersection portions 19a, in which three or more spray areas 17 overlap, further increasing the efficiency and uniformity of the cooling performed.

By intervening on the closing valves 23, each row X, or column Y, can be fed individually or in groups, so as to define, within the same cooling module 11, different cooling zones.

The cooling module 11 comprises, in the lower part of the hollow space 12, at least one circuit for the collection and evacuation of the waste coolant fluid, shown schematically in the attached drawings with only the outlet pipe coupling 25, from which the fluid exits to be sent to its collection.

In addition, the apparatus 10 comprises at least one temperature detection element 26, of a substantially known type and only schematized in fig. 3. This detection element 26 is arranged to detect the cooling temperature of the perimeter wall, and it is connected to a command and control unit 27 so that the latter makes a comparison between the data detected and predetermined system data, so as to alert a user device, and possibly intervene on the process steps of the furnace 100, or of the apparatus 10. Advantageously, the detection elements 26 can be installed on the panel 200 at points of greater exposure with respect to the electrodes 300, and therefore at the shortest distance in a straight line between the panel 200 and each electrode 300.

It is clear that modifications and/or additions of parts may be made to the apparatus 10 and to the furnace 100 provided with such apparatus 10 as described heretofore, without thereby departing from the field and scope of the present invention, as defined by the claims.

It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art will be able to achieve other equivalent forms of cooling apparatus for a metallurgical furnace and metallurgical furnace provided with such apparatus, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby. In the following claims, the sole purpose of the references in brackets is to facilitate their reading and they must not be considered as restrictive factors with regard to the field of protection defined by the claims.

Claims

1. Cooling apparatus (10) for a metallurgical furnace (100), in which at least one container (110) is provided with at least one perimeter wall (130), with which there is associated at least one cooling module (11) provided with a plurality of nozzles (15) arranged to spray a coolant fluid against a first element (200) of said perimeter wall (130), characterized in that each of said nozzles

defines a spraying cone (16) of said coolant fluid against said first element (200) with a certain angle (a) of amplitude and is positioned at a first distance (DI) from another adjacent nozzle (15), so that the ratio between said angle (a) and said first distance (DI) is at least such that each spraying cone (16) defines a spray area (17) on said first element (200) and an intersection portion (19) with a spraying cone (16) of an adjacent nozzle (15), wherein said at least one cooling module (11) comprises feeding lines (20) of the coolant fluid to which said nozzles (15) are hydraulically connected, said feeding lines (20) being arranged so as to define a plurality of rows (X), or columns (Y), of nozzles (15) and being hydraulically connected to at least one coolant fluid feeding manifold (21), said manifold (21) being annular and positioned, during use, along said perimeter wall (130).

2. Apparatus (10) as in claim 1, characterized in that each feeding line (20) can be selectively isolated from the other feeding lines (20) by means of corresponding closing valves (23), so as to possibly feed single rows (X) and/or columns (Y) of nozzles (15), or groups of rows (X) and/or columns (Y) of nozzles (15) with coolant fluid.

3. Apparatus (10) as in claim 1 or 2, characterized in that columns (Y) of nozzles (15) located in succession are separated by a first distance (DI) and rows (X) of nozzles (15) located in succession are separated by a second distance (D3), said distances (DI, D3) being such as to allow high intersection portions (19a), in which three or more spray areas (17) overlap.

4. Apparatus (10) as in claim 3, characterized in that said first distance (DI) is comprised between 300 mm and 400 mm, and said second distance (D3) is comprised between 350 mm and 500 mm.

5. Apparatus (10) as in one or other of the previous claims, characterized in that said feeding lines (20) comprise lateral branches (28) which carry the coolant fluid to said nozzles (15).

6. Apparatus (10) as in one or the other of the previous claims, characterized in that said intersection portion (19) has a surface comprised between approximately 5% and approximately 65% of each spray area (17).

7. Apparatus (10) as in one or the other of the previous claims, wherein said metallurgical furnace (100) comprises a closing vault (150) able to selectively close from above the melting chamber (160) of said perimeter wall (130) provided with a second element (250) directly facing said melting chamber (160), characterized in that said cooling module (11) is associated with said closing vault (150) and each of its nozzles (15) is arranged to define a spraying cone (16) of said coolant fluid against said second element (250), defining a spray area (17) and an intersection portion (19) with the spraying cone (16) of an adjacent nozzle (15).

8. Apparatus (10) as in one or the other of the previous claims, characterized in that each of said nozzles (15) is positioned at a second distance (D2) from said first element (200), or from said second element (250), comprised between 150 mm and 300 mm.

9. Apparatus (10) as in one or the other of the previous claims, characterized in that said cooling module (11) comprises at least one feeding line (20) able to feed said coolant fluid to said nozzles (15) individually or in groups. 10. Apparatus (10) as in one or the other of the previous claims, characterized in that it provides a single cooling module (11) partly or totally distributed on said perimeter wall (130), or on said vault (150), or a plurality of cooling modules (11) comprised between two and seven, distributed on said perimeter wall (130), or on said vault (150). 11. Apparatus ( 10) as in claim 10, characterized in that each cooling module (11) comprises a number of nozzles (15) comprised between five and eleven, even different between the cooling modules (11), fed individually or in groups by said feeding lines (20).

12. Apparatus (10) as in claim 10 or 11, characterized in that each cooling module (11) comprises a circuit (25) for the collection and evacuation of the waste coolant fluid.

13. Apparatus (10) as in one or the other of the previous claims, characterized in that it comprises at least one element (26) for detecting the cooling temperature of said first element (200) and a command and control unit (27) connected at least to said detection element (26).

14. Metallurgical furnace (100) provided with at least one container (110) having at least one perimeter wall (130), and with which there is associated a cooling apparatus ( 10) as in any claim hereinbefore comprising at least one cooling module (11) associated at least with said perimeter wall (130) and provided inside it with a plurality of nozzles (15) arranged to spray a coolant fluid against a first element (200) of said perimeter wall (130), characterized in that each of said nozzles (15) is arranged to define a spraying cone (16) of said coolant fluid against said first element (200) with a certain angle (a) of amplitude and is positioned at a first distance (DI) from an adjacent nozzle (15), the ratio between said angle (a) and said first distance (DI) is at least such that each spraying cone (16) defines a spray area (17) on said first element (200) and an intersection portion (19) with the spraying cone (16) of said adjacent nozzle (15), wherein said at least one cooling module (11) comprises feeding lines (20) of the coolant fluid, to which said nozzles

(15) are hydraulically connected, said feeding lines (20) being arranged so as to define a plurality of rows (X), or columns (Y), of nozzles (15) and being hydraulically connected to at least one coolant fluid feeding manifold (21), said manifold (21) being annular and positioned, during use, along said perimeter wall (130).

15. Metallurgical furnace (100) as in claim 14, characterized in that it comprises a single cooling module (11) integrated into a hollow space (12) of said perimeter wall (130), the hollow space (12) being defined, at least on one side, by said first element (200). 16. Metallurgical furnace (100) as in claim 15, characterized in that said manifold

(21) is disposed circularly inside the hollow space (12) and is open toward the outside of the perimeter wall (130), by means of at least one pipe union (22).

17. Metallurgical furnace (100) as in one or other of the previous claims, characterized in that one or more inspection doors (13) are provided on the perimeter wall (130) to allow the inspection of the cooling module/s (11), or parts thereof.