glass manufacturing furnace reinforcement

Abstract

The present invention provides a glass furnace that is at least partially electric and suitable for melting vitrifiable materials. [Solution] The present invention relates to a glassmaking furnace (1) which is at least partially electric, comprising a melting tank (2) made of blocks of refractory material and suitable for containing a bath (3) of molten vitrifiable material, and a plurality of heating electrodes (4) suitable for supplying power to the bath, wherein the tank (2) is held in place by a metal reinforcement (6), and the reinforcement (6) comprises a set of electrical insulators (7) which form an electrical confinement barrier for the tank (2) that can block the circulation of leakage current between the tank (2) and the metal reinforcement (6) of the furnace.

Description

[Technical Field]

[0001] The present invention belongs to the general field of glassmaking. More specifically, the present invention relates to a glass furnace that is at least partially electric and suitable for melting vitrifiable materials. The present invention also relates to a method for melting vitrifiable materials so that glass can be produced. The present invention is particularly useful in applications in the manufacture of glass wool, rock wool, textile glass yarn and / or flat glass or hollow glass, but is not limited to these applications. [Background technology]

[0002] In this specification, “vitrified material” or “raw material” is understood to mean all materials that can be included in a composition supplied to a glass furnace, including natural ore or synthetic products, recycled materials such as cullet. This includes silica sand, but also all additives (such as sodium carbonate, limestone, dolomite, and alumina), waste materials that can be produced from fiber manufacturing or construction or demolition sites (including mineral fibers), all possible liquid or solid fuels (composite or non-composite plastics, organic materials, coal), and any type of cullet. It also includes recyclable materials containing combustible (organic) elements, such as sizing mineral fibers with binders (of the type used for thermal or acoustic insulation, or for reinforcing plastics), glazing laminated with sheets of polyvinyl butyral polymer, such as windshields, glass bottles (household cullet), or any type of “composite” material combining glass and plastic materials, such as certain bottles. “Glass-metal composites or metal compounds,” such as functionalized glazing with metal-containing coatings, are also recyclable. In this specification, "bath of vitrifiable material" or "glass bath" refers to the product obtained by melting these raw materials.

[0003] Similarly, "glass" is understood to mean glass in a broad sense, that is, any material having a glassy, ​​glass-ceramic, or ceramic matrix.

[0004] In addition, the term “manufacturing” includes the essential process of melting the vitrifiable material and, if necessary, all subsequent processes of refining / preparing the molten glass for its final form, in particular all subsequent processes of refining / preparing the molten glass for its final form, such as flat glass (glazing), hollow glass (bottles, jars), glass in the form of mineral wool (especially rock wool or glass wool) used for its thermal or sound insulation properties, and glass in the form of textile yarn used for reinforcement.

[0005] Various examples of electric furnace designs are known from the technical level, in which an electric current is conducted through heating electrodes in a bath of vitrifiable material. Such electrodes may be of the "immersion" type, positioned vertically from the hearth into the bath or passing horizontally through the side walls of the furnace, and / or of the "plunge" type, immersed from the free surface of the bath.

[0006] Surprisingly, the inventors have found the presence of leakage currents through the molten bath of a glass furnace made of refractory material, despite the electrical insulation properties of the refractory material. This is due to a localized reduction in the thickness of the bath, resulting from corrosion of the refractory material by the glass bath over the life of the furnace and / or from corrosion of the refractory material due to the penetration of electrically conductive liquid glass into the thickness of the bath. These undesirable leakage currents lead to localized heating of the refractory material, adversely affecting its durability. Furthermore, they result in unnecessary energy loss, which affects the energy balance of the furnace. Grounding short circuits caused by these leakage currents can also damage the equipment. Finally, these leakage currents increase the risk of potentially fatal electric shock to operators located near the furnace in the event of accidental contact with live parts.

[0007] The discovery of leakage currents flowing through the molten chamber of a glass furnace made of refractory material is an important part of this invention. [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] The objective of the present invention is to improve upon the shortcomings of the prior art, particularly some or all of the aforementioned shortcomings. [Means for solving the problem]

[0009] For this purpose, according to a first aspect, the present invention relates to at least partially electric glass furnace comprising a block made of a refractory material suitable for containing a bath of molten vitrifiable material, and a plurality of heating electrodes suitable for supplying power to the bath, wherein the bath is held in place by a metal reinforcement, and the furnace comprises a set of electrical insulators, the reinforcement forming an electrical confinement barrier for the bath. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 schematically shows the external view of an electric glass furnace according to a specific embodiment of the present invention. [Figure 2] Figure 2 schematically shows the outline of an electrical insulator of a type attached to a pusher of a reinforcing material in an electric glass furnace, according to a particular embodiment of the present invention. [Figure 3] Figure 3 schematically shows the outline of a type of electrical insulator, in this case a sleeve, attached to a reinforcing member of an electric glass furnace according to a particular embodiment of the present invention. [Figure 4] Figure 4 schematically shows the outline of a type of electrical insulator, in this case a brick, attached to the reinforcing material of an electric glass furnace according to a particular embodiment of the present invention. [Figure 5] Figure 5 is a flowchart showing a series of steps in a manufacturing method according to a specific embodiment of the present invention.

[0011] By definition, according to the present invention, the electric confinement "barrier" of at least the tank, and preferably additionally the crown, means an obstruction to leakage current formed by a set of electrical insulators used in the glass furnace to obtain electric confinement, thereby improving the shortcomings of the prior art detailed above.

[0012] The electrically confined barrier according to the present invention, formed by a set of electrical insulators, is configured to block the circulation of leakage current from the furnace chamber, or even from the crown, to the metal reinforcement. In other words, the electrically confined barrier can prevent the passage of leakage current from the furnace chamber, or even from the crown, to the metal reinforcement.

[0013] Thanks to the electrical confinement barrier according to the present invention, when such leakage currents are present in the tank, these leakage currents are not further transmitted to the metal reinforcement; in other words, the current passing through the block of refractory material remains confined within the furnace, the tank, or even the crown, inside the metal reinforcement that holds the block of refractory material in place.

[0014] In fact, a set of electrical insulators is configured to prevent any transmission of leakage currents present in the furnace chamber or even the refractory block of the crown, particularly to the metal reinforcement.

[0015] In a non-limiting manner, the risk of electric shock in the event of accidental contact with a portion of the metal reinforcement activated by an operator near the furnace is advantageously eliminated by the electric confinement barrier formed by the aforementioned set of electrical insulators.

[0016] Advantageously, the electrically confined barrier according to the present invention further makes it possible to avoid grounding the glass contained in the tank and / or the tank itself.

[0017] For the purposes of the present invention, a metal reinforcement refers to an assembly intended to hold together, reinforce and support various parts of a tank made of refractory material, in particular blocks made of refractory material forming the hearth and the crown of a furnace.

[0018] For the purposes of the present invention, and in accordance with the ISO / R836 or AFNOR NF B 40-001 standards, "refractory material" is defined as a material and product other than metals and alloys (not excluding those containing metallic components) whose heat resistance is at least equal to 1500°C. This definition means that refractory materials must withstand at least 1500°C without softening or collapsing under their own weight in accordance with the high-temperature strength test standard. As is well known, a glass furnace made of refractory material comprises a set of blocks made of refractory material, which are assembled to form the hearth and the crown of the furnace and are held in position via metal reinforcements.

[0019] On the one hand, the present invention is based on the inventors' surprising observation regarding the existence of leakage currents passing through the melting hearth of a glass furnace made of these refractory materials despite their electrical insulation properties, and on the other hand, it consists of a new inventive idea which consists in equipping the metal reinforcements holding the hearth in position with a set of electrical insulators in order to electrically confine this melting hearth and thus avoid or at least limit the generation of these leakage currents.

[0020] Preventing these leakage currents limits the risk of premature damage to the hearth (tank), reduces the energy consumption of the furnace or at least optimizes its melting capacity, prevents earth faults that could damage the installation, and eliminates the risk of electric shock to the operator.

[0021] According to a particular embodiment, the glass furnace comprises a crown, preferably a low-temperature crown, held in position by metal reinforcements, and the set of electrical insulators also forms an electrical confinement barrier for the crown.

[0022] According to certain embodiments, the metal reinforcement of the furnace comprises a pusher for holding the side wall of the tank or the crown, and all or at least a part of the pusher, preferably at least 80%, or even 90%, or even 95%, more preferably each of the holding pushers, is electrically insulated by at least one electrical insulator of a set of electrical insulators, and in this way, an electrical confinement barrier for the tank or even for the crown is formed.

[0023] Advantageously, a set of electrical insulators may actually be shared between at least two holding pushers, depending on its arrangement, for example of the "direct" or "remote" mounting type, for example by the use of plates, and thus each electrical insulator of the set of electrical insulators is not necessarily associated with a single holding pusher. Preferably, the glass furnace comprises the least possible number of holding pushers.

[0024] According to certain embodiments, at least some of the blocks made of refractory material of the tank or the crown form side walls defining an outer surface, and at least 80%, or even 90% thereof, is in direct or indirect contact with a set of electrical insulators forming an electrical confinement barrier for the tank or even for the crown. [[ID=J10]]

[0025] In other words, at least most of the outer surface of the side wall made of refractory blocks is advantageously electrically confined by a set of electrical insulators.

[0026] According to certain embodiments, at least the blocks made of refractory material of the tank or even of the crown are electrically insulated from the metal reinforcement, directly or indirectly, by the said number N of the set of electrical insulators, and preferably, the said number N of electrical insulators is equal to or less than the number of blocks made of refractory material.

[0027] In other words, the number of electrical insulators in a set is not necessarily equal to the number of blocks, even though each block has an associated electrical insulator, and can be relatively few if the electrical insulators are favorably shared, as long as it does not negatively affect the acquisition of an electrical confinement barrier for at least the tanks of the glass furnace.

[0028] According to a particular embodiment, at least one electrical insulator is positioned in direct contact with the tank or crown.

[0029] By arranging the electrical insulator in this manner, the area where current can flow is spatially limited, and therefore the risk of electric shock is reduced.

[0030] According to a particular embodiment, at least one electrical insulator is separated from the tank or crown via at least one element of a reinforcing material such as a plate and / or flat iron material.

[0031] While this type of "remote" mounting of electrical insulators is easier to implement, it has the disadvantage of extending the zone in which the reinforcing material can conduct electricity.

[0032] According to a particular embodiment, the reinforcing member comprises at least one pusher for holding the side wall of the tank or crown, preferably via a grate, angle, or U-shaped iron, or plate, and at least one electrical insulator disposed between the pusher and the tank or crown, preferably on one side between the pusher and on the other side between the grate, iron, or plate.

[0033] Therefore, such pushers are an example of an electrical insulator that is suitable for alternative mounting, either in direct contact with the tank or crown, or in a “remote” manner within the reinforcing material.

[0034] According to a particular embodiment, a set of electrical insulators comprises an electrical insulating sleeve of a plate or shaft intended to be in electrical contact with a tank or crown.

[0035] Therefore, such sleeves are an example of an electrical insulator suitable for "remote" mounting within reinforcement materials.

[0036] According to a particular embodiment, a set of electrical insulators comprises bricks, preferably made of zircon, adapted to electrically insulate beam and / or flat iron materials intended to be in contact with a tank or crown, the bricks preferably mounted within a “top hat” iron material.

[0037] Therefore, such bricks are an example of an electrical insulator suitable for "remote" installation within reinforcement.

[0038] According to a particular embodiment, at least one of the electrical insulators belongs to the group that includes zircon, or any other fire-resistant or insulating material, such as Isoref C140, or dielectric material, such as composite fiber (epoxy glass, fibrocement), or mica-based material laminated with resin.

[0039] At least one of the electrical insulators is selected from, for example, an insulator having high electrical resistivity and high compressive strength, such as the aforementioned Isoref C140, or from a high-performance plastic.

[0040] The materials in this group possess a combination of electrical insulation and mechanical barrier properties, and are therefore particularly well suited to the present invention.

[0041] According to certain embodiments, a set of electrical insulators also forms an electrical confinement barrier for heating electrodes.

[0042] The inventors have actually observed the presence of leakage current circulating through the heating electrodes. Electrical insulation of these heating electrodes provides a solution to this risk.

[0043] According to a particular embodiment, the glass furnace comprises at least one instrument, preferably a thermocouple, for measuring physical variables within the tank and / or crown, and a set of electrical insulators also forms an electrical confinement barrier for the measuring instrument.

[0044] The inventors have actually observed the presence of circulating leakage current through such measuring instruments. Electrical insulation of these measuring instruments provides a solution to this risk.

[0045] According to a particular embodiment, the glass furnace is electrically operated as a whole, preferably includes a low-temperature crown, and the bath of molten vitrifiable material is 6 m 2 Exceeding 13m, preferably 13m 2 Exceeding 19m, preferably 19m 2 Exceeding 25m, preferably 25m 2 More than 40m 2 More than 60m 2 Exceeding 100m, preferably 100m 2 The melting tank is characterized by having a surface area exceeding a certain value, and preferably having a distance between two opposing walls of the tank that is greater than 2.5 m, preferably greater than 3.1 m, preferably greater than 5 m, and preferably greater than 6.5 m.

[0046] These dimensions relate to so-called large electric furnaces, where the use of a two-phase system is particularly advantageous.

[0047] According to certain embodiments, the glass furnace is of a hybrid type and comprises combustion heating means, preferably immersion and / or floating burners, as well as a hot crown.

[0048] According to a particular embodiment, at least one heating electrode protrudes from the free surface of the bath and is supplied with current by an electrical installation adapted to generate a two-phase or three-phase alternating current.

[0049] Compared with so-called "immersion" type electrodes, plunger electrodes (input electrodes) offer many advantages. First, they avoid the difficulties associated with the passage of immersion electrodes through refractories, as well as the problems of replacing these electrodes when worn, the problems of sealing the melting tank, or even the problems of refractory wear caused by high temperatures, which are particularly advantageous for refractory attack, and caused by strong convection occurring in the vicinity of the electrodes during operation.

[0050] Three-phase current offers many advantages. In particular, this is the so-called "industrial" current that is customarily distributed to factories by energy suppliers, and thus provides the fact of compatibility with the resulting device. Three-phase current supplies, for example, instantaneous power without a pulse component, unlike single-phase current. However, it should be noted that the principle of phase balance tends to lead to a triangular or hexagonal arrangement of electrodes on the surface of the glass bath. Such geometric constraints do not seem to pose theoretical problems in the context of small electric furnaces, but pose problems in the context of large electric furnaces. In this case, the glass bath extends over more than 25 m 2 super, preferably more than 49 m 2 super and the width between the edges of the glass bath is more than 5 m, preferably more than 7 m. In such a configuration, considering the aforementioned geometric constraints, the current tends to concentrate between the same and / or adjacent tank edge electrodes. Therefore, the distance covered by the current in the glass bath, and thus the resistance of the glass bath to the passage of this current, decreases. For a given power corresponding to the energy required to melt the vitrifiable material, and in the context of a glass bath that only provides a reduced resistance, it is necessary to increase the intensity of the current delivered. However, along with the intensity of the current supplied per electrode, the wear of the electrodes and refractories constituting the tank increases. To overcome this wear problem, the natural solution is to distribute the current supplied between a greater number of electrodes. However, this has the drawback of increasing the operating costs of these electrodes, as these electrodes increase without solving the specific problem of non-uniform current distribution in the glass bath.

[0051] According to a particular embodiment, the present invention relates to a method for melting a vitrifiable material carried out by such a glass furnace, characterized by comprising at least one step of electrically heating a bath of molten vitrifiable material with a plurality of electrodes.

[0052] According to certain embodiments, the present invention also relates to a method for producing glass wool, rock wool, glass textile yarn and / or flat or hollow glass, characterized by employing such a melting method.

[0053] Other features and advantages of the present invention will become apparent from the non-limiting description given below with reference to the accompanying drawings illustrating exemplary embodiments thereof.

[0054] Figure 1 schematically shows the external view of an electric glass furnace according to a specific embodiment of the present invention. Figure 2 schematically shows the outline of an electrical insulator of a type attached to a pusher of a reinforcing material in an electric glass furnace, according to a particular embodiment of the present invention. Figure 3 schematically shows the outline of a type of electrical insulator, in this case a sleeve, attached to a reinforcing member of an electric glass furnace according to a particular embodiment of the present invention. Figure 4 schematically shows the outline of a type of electrical insulator, in this case a brick, attached to the reinforcing material of an electric glass furnace according to a particular embodiment of the present invention. Figure 5 is a flowchart showing the sequence of steps of a manufacturing method according to a specific embodiment of the present invention.

[0055] Figure 1 schematically shows the outline of an electric glass furnace 1. Such a glass furnace 1 comprises a melting tank 2 made of a refractory material suitable for containing a bath 3 of vitrifiable material, and a plurality of electrodes 4, including an immersion electrode (only one is shown in Figure 1 for simplicity of explanation) and a plunge electrode immersed from the free surface of the bath 3, the arms of which have a square cross-section. All of these electrodes 4 are supplied with current by an electrical installation. The glass furnace 1 according to the present invention is particularly characterized in that the electrical installation is adapted to generate a two-phase alternating current.

[0056] According to a particular embodiment shown in Figure 1, the furnace 1 is entirely electric and includes a low-temperature crown 5. According to an alternative embodiment, such a glass furnace is of the hybrid type and, in addition to electrodes, includes combustion heating means, preferably immersion and / or floating burners, as well as a high-temperature crown.

[0057] As shown in Figure 1, the tank 2 and crown 5 are held in place by a metal reinforcement 6. This reinforcement 6 includes a set of electrical insulators 7 that form an electrical confinement barrier for the tank 2 and crown 5. In this way, it is possible to avoid, or at least limit, the generation of leakage current from the glass bath. These electrical insulators can take on different forms, as detailed in the remainder of this specification, and can be implemented in different mechanical systems within the metal reinforcement.

[0058] Advantageously, all electrical insulators forming the electrical confinement barrier of the vessel are numbered and arranged to prevent the circulation of leakage current. A set of electrical insulators is configured to form at least an electrical confinement barrier for the vessel of the glass furnace. In other words, a set of electrical insulators can electrically confine at least the vessel of the furnace, thereby blocking any circulation of leakage current through the metal reinforcement, thereby eliminating, in particular, the risk of electric shock.

[0059] Advantageously, a set of electrical insulators is positioned to minimize leakage current loops, which is why their number and arrangement should be adapted to each furnace, and in particular, based on the number of pushers, all or at least some of which are electrically insulated.

[0060] The embodiment of the glass furnace shown in Figure 1 demonstrates that an electric confinement barrier for the tank is obtained using a set of electric insulators, including different electric insulators configured to provide electric confinement for the tank, or even for the crown.

[0061] According to a particular embodiment shown in Figure 2, such an electrical insulator 7 is attached to a pusher 8 that holds the side wall of the tank 2 (or crown 5). More precisely, the electrical insulator 7 in the form of a plate is positioned between the pusher 8 and the tank 2 in direct contact with the tank 2. As shown in Figure 1, a grid, angle or U-shaped iron or plate 14 may be positioned between the electrical insulator 7 and the tank 8, in particular to distribute the compressive force applied by the pusher 8 over a larger surface area of ​​the tank. In this case, the electrical insulator 7 is positioned according to a so-called “remote” assembly, because it is separated from the tank 2 by at least one element of the metal reinforcement 6.

[0062] According to a particular embodiment shown in Figure 3, a set of electrical insulators 7 includes an electrical insulating sleeve 9 arranged around a metal plate 11, which itself is in electrical contact with the tank 2 (or crown 5). The sleeve 9 is arranged in this case according to a so-called “remote” assembly because it is separated from the tank 2 by at least one element of the metal reinforcement 6, in this case the metal plate 11.

[0063] According to a particular embodiment shown in Figure 4, a set of electrical insulators 7 comprises bricks 10 made of zircon or any other fire-resistant or insulating material having sufficient electrical resistivity and compressive strength, such as Isoref C140, which are positioned between a “top hat” iron member 13 on the one hand and a flat iron member 12 on the other, the flat iron member 12 itself being in contact with the bottom of the tank 2. The bricks 10 are positioned in this case according to a so-called “remote” assembly because they are separated from the tank 2 by at least one element of the metal reinforcement 6, in this case the flat iron member 12.

[0064] Figure 5 is a flowchart showing a series of steps (processes) of a manufacturing method according to a particular embodiment of the present invention, comprising a first step S1 of melting a vitrifiable material by electrically heating a bath 3 of the vitrifiable material with a two-phase alternating current, and a second step S2 of producing glass wool, rock wool, glass textile yarn, and / or flat or hollow glass.

[0065] According to the present invention, the reinforcing member 6 of the glass furnace 1 comprises a set of electrical insulators 7 configured to form an electrical confinement barrier for the tank 2 or even the crown 5, which can also interrupt the circulation of any leakage current between the furnace tank 2 and the metal reinforcing member 6.

[0066] In other words, the metal reinforcement 6 of the furnace comprises a pair of electrical insulators 7 that form an electrical confinement barrier for the tank 2, thereby blocking any leakage currents originating from the tank 2 by the pair of electrical insulators 7, thereby preventing these currents from being transmitted to the metal reinforcement 6, particularly via the retaining pushers 8, and advantageously, the leakage currents (if any) remain confined within the furnace, in the tank 2, or even further, in the crown 5.

[0067] The electric confinement barrier according to the present invention advantageously eliminates the risk of electric shock due to contact with the metal reinforcing material 6.

Claims

1. A glass furnace (1) that is at least partially electric and comprises a melting tank (2) consisting of a plurality of blocks made of refractory material and suitable for containing a bath (3) of molten vitrifiable material, and a plurality of heating electrodes (4) suitable for supplying power to the bath, wherein the tank (2) is held in place by a metal reinforcement (6), The glass furnace (1) is characterized in that the reinforcing material (6) comprises a set of electrical insulators (7) that form an electrical confinement barrier for the tank (2).

2. The glass furnace (1) according to claim 1, wherein the furnace comprises a crown (5), preferably a low-temperature crown, the crown consisting of a plurality of blocks made of a refractory material and held in place by the reinforcing member (6), and the set of electrical insulators (7) also form an electrical confinement barrier for the crown (5).

3. The glass furnace (1) according to claim 1 or 2, wherein the metal reinforcing member (6) comprises pushers (8) for holding the side walls of the tank (2) or the crown (5), and all or at least part of the pushers, preferably at least 80%, or more preferably 90%, or more preferably 95%, of the pushers, or more preferably each of the holding pushers, is electrically insulated by at least one electrical insulator (7) of the set of electrical insulators (7), thereby forming the electrical confinement barrier for the tank (2) or the crown (5).

4. The glass furnace (1) according to any one of claims 1 to 3, wherein at least some of the plurality of blocks made of refractory material of the tank (2) or the crown (5) form side walls defining an outer surface, and at least 80%, or even more than 90%, of the outer surface is in direct or indirect contact with the set of electrical insulators forming the electrical confinement barrier for the tank (2) or even the crown (5).

5. A glass furnace (1) according to any one of claims 1 to 4, characterized in that at least the plurality of blocks made of refractory material of the tank (2), or even the crown (5), are electrically insulated directly or indirectly from the metal reinforcement (6) by a set of several N electrical insulators (7), preferably the number of several N electrical insulators (7) is less than or equal to the number of the plurality of blocks made of refractory material.

6. The glass furnace (1) according to any one of claims 1 to 5, characterized in that at least one electrical insulator (7) is arranged in direct contact with the tank (2) or the crown (5).

7. The glass furnace (1) according to any one of claims 1 to 6, characterized in that at least one electrical insulator (7) is separated from the tank (2) or the crown (5) by at least one element of the reinforcing material (6), for example by plates (11, 14) and / or flat iron material (12).

8. The glass furnace (1) according to any one of claims 1 to 7, characterized in that the reinforcing member (6) comprises at least one pusher (8) for holding the side wall of the tank (2) or the crown (5) by means of a grid, angle, or U-shaped iron material or plate (14), and at least one electrical insulator (7) disposed between the pusher (8) and the tank (2) or the crown (5), preferably disposed on one side between the pusher (8) and on the other side between the grid, iron material or plate.

9. The glass furnace (1) according to any one of claims 1 to 8, characterized in that the set of electrical insulators (7) includes a sleeve (9) for electrically insulating a plate (11) or shaft intended to be in electrical contact with the tank (2) or the crown (5).

10. The glass furnace (1) according to any one of claims 1 to 9, wherein the set of electrical insulators (7) preferably comprises a brick (10) made of zircon and is adapted to electrically insulate beam material and / or flat iron material (12) intended to be in contact with the tank (2) or the crown (5), and the brick (10) is preferably installed within a "top hat" iron material (13).

11. The glass furnace (1) according to any one of claims 1 to 10, characterized in that at least one of the electrical insulators (7) belongs to the group including zircon, or any other fire-resistant or insulating material, such as Isoref C140, or dielectric material, such as composite fiber (epoxy glass, fibrocement), or mica-based material laminated with resin.

12. The glass furnace (1) according to any one of claims 1 to 11, characterized in that the set of electrical insulators (7) also forms an electrical confinement barrier for the heating electrode (4).

13. The glass furnace (1) according to any one of claims 1 to 12, comprising at least one instrument, preferably a thermocouple, for measuring physical variables in the tank (2) and / or the crown (5), wherein the pair of electrical insulators (7) also form an electrical confinement barrier for the measuring instrument.

14. A glass furnace (1) according to any one of claims 1 to 13, wherein it is fully electrically operated, preferably includes a low-temperature crown, and preferably the bath of the molten vitrifiable material is 6 m ２ More preferably 13m ２ More preferably 19m ２ More preferably 25m ２ More preferably 40m ２ More preferably 60m ２ More preferably 100m ２ A glass furnace (1) characterized in that it has a surface area greater than or equal to and the melting tank is sized such that the distance between the two opposing walls of the tank is preferably greater than 2.5 m, preferably greater than 3.1 m, preferably greater than 5 m, and preferably greater than 6.5 m.

15. A glass furnace (1) according to any one of claims 1 to 14, characterized in that it is a hybrid type and includes a combustion heating means, preferably an immersion and / or floating burner, and a high-temperature crown.

16. The glass furnace (1) according to any one of claims 1 to 15, characterized in that at least one heating electrode (4) protrudes from the free surface of the bath (3) and is supplied with current by an electrical installation adapted to generate a two-phase or three-phase alternating current.

17. A method for melting a vitrifiable material carried out in a glass furnace according to any one of claims 1 to 16, characterized by comprising at least one step (S1) of electrically heating the bath (3) of the vitrifiable material molten by the plurality of electrodes (4).

18. A method for producing glass wool, rock wool, glass textile fibers and / or flat glass or hollow glass (S2), characterized by carrying out the melting method described in claim 17.

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