WO2009013410A2 - Device for limiting the combustion fume exhaust at the entrance of a furnace for reheating iron and steel products - Google Patents

Device for limiting the combustion fume exhaust at the entrance of a furnace for reheating iron and steel products Download PDF

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Publication number
WO2009013410A2
WO2009013410A2 PCT/FR2008/000869 FR2008000869W WO2009013410A2 WO 2009013410 A2 WO2009013410 A2 WO 2009013410A2 FR 2008000869 W FR2008000869 W FR 2008000869W WO 2009013410 A2 WO2009013410 A2 WO 2009013410A2
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WO
WIPO (PCT)
Prior art keywords
burners
furnace
oven
row
products
Prior art date
Application number
PCT/FR2008/000869
Other languages
French (fr)
Other versions
WO2009013410A3 (en
Inventor
René-Vincent CHEVER
Philippe Reynes
Sébastien LEMAIRE
Original Assignee
Fives Stein
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fives Stein filed Critical Fives Stein
Priority to BRPI0813401-4A2A priority Critical patent/BRPI0813401A2/en
Priority to EP08826510A priority patent/EP2156125A2/en
Priority to US12/664,188 priority patent/US20100183992A1/en
Publication of WO2009013410A2 publication Critical patent/WO2009013410A2/en
Publication of WO2009013410A3 publication Critical patent/WO2009013410A3/en

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C5/00—Disposition of burners with respect to the combustion chamber or to one another; Mounting of burners in combustion apparatus
    • F23C5/08—Disposition of burners
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/34—Methods of heating
    • C21D1/52—Methods of heating with flames
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/0056—Furnaces through which the charge is moved in a horizontal straight path
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
    • C21D9/54—Furnaces for treating strips or wire
    • C21D9/56—Continuous furnaces for strip or wire
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
    • C21D9/54—Furnaces for treating strips or wire
    • C21D9/56—Continuous furnaces for strip or wire
    • C21D9/562—Details
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/30—Details, accessories, or equipment peculiar to furnaces of these types
    • F27B9/36—Arrangements of heating devices
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/30—Details, accessories, or equipment peculiar to furnaces of these types
    • F27B9/36—Arrangements of heating devices
    • F27B2009/3607—Heaters located above the track of the charge
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/30—Details, accessories, or equipment peculiar to furnaces of these types
    • F27B9/36—Arrangements of heating devices
    • F27B2009/3638—Heaters located above and under the track
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D99/00—Subject matter not provided for in other groups of this subclass
    • F27D99/0001—Heating elements or systems
    • F27D99/0033—Heating elements or systems using burners

Definitions

  • the present invention relates to a device for limiting the exhaust of combustion fumes to the outside of a continuous furnace for heating steel products and in particular slabs, in particular a tunnel furnace, at the opening located at the entrance of the oven.
  • a tunnel kiln usually has its inlet open at all times to allow the flow of products coming for example from the continuous casting upstream in the process of developing flat products.
  • the inlet section of the oven is kept to a minimum to limit smoke exhaust and heat radiation to the outside of the oven.
  • This harmful phenomenon is directly related to the existing overpressure in the first heating zone of the furnace, the flue usually located in the homogenization zone does not allow to draw enough fumes. This causes degradation of the oven walls at the level of charging and poses problems to the equipment located in the hall near and above the oven.
  • FIG.1 An example of the beginning of tunnel furnace is shown in Fig.1 of the accompanying drawings.
  • the direction of travel of the products to be heated is indicated by the arrows placed at both ends of the portion of the furnace shown. From the product inlet are shown three successive heating zones, 1a, 1b, 1c, followed by two homogenization zones 1d and 1e.
  • a chimney 3 allows the extraction of combustion fumes.
  • the oven is heated by burners 2 placed on the side walls of the oven, below and above the products to be heated.
  • the direction of travel of the products to be heated is also indicated by the arrows placed at both ends of the heating zone.
  • the burners are placed in staggered rows; for a burner located below the product on one side of the oven, on the opposite side and for the same distance from the oven inlet, the burner is above the product.
  • the chimney 3 for the evacuation of combustion fumes produced by the burners is in this example placed in the second equalization zone 1e.
  • FIG. 3 we can see a curve showing the variation of the pressure in the oven for the embodiment of Fig.2.
  • the length of the oven is indicated on the abscissa from the entry, abscissa 0 meter, until the end of the second equalization zone corresponding to the abscissa 110 meters.
  • the pressure in the furnace is indicated on the ordinate, the value zero corresponds to the atmospheric pressure prevailing outside the furnace, a positive pressure of 5 Pa (pascals) is a pressure in the furnace 5 Pa higher than the pressure at the furnace. Outside the oven, a negative pressure of 5 Pa is a pressure in the oven 5 Pa lower than the pressure outside the oven.
  • Fig. 3 the pressure relative to the inlet of the oven is about 8 Pa. This causes the exhaust fumes outside the oven.
  • the depression in the second part of the furnace is relatively large, of the order of -25 Pa, which may result in a return of fumes from the downstream areas.
  • the pressure difference between the charging and the second part of the oven reaches 30 Pa.
  • Fig. 4 represents an example embodiment of this type, the second draw of the fumes at the furnace inlet bearing the mark 4.
  • the pressure in the oven varies from the inlet of the oven according to FIG. 5. It is found that the addition of a second draft of the fumes at the entrance of the oven makes it possible to obtain a more uniform pressure over the length of the oven, with a pressure difference between the charging and the rest of the oven limited to about 15 Pa because the pressure is raised in the second part of the furnace to reach a value of -10 Pa. However, the overpressure at the entrance of the tunnel kiln has not been attenuated and the risk of smoke escaping persists. Furthermore, the addition of this second draw fumes at the entrance of the oven leads to significant additional cost because of this additional equipment.
  • a variant of this configuration shown in FIG. 6 and in FIG. 7 consists in placing two burners 2a1,2b1; 2c1, 2d1 on each side of the oven, below and above the product to be heated so as to have two pairs of burners vis-à-vis.
  • Two burners 2a1 and 2b1 are placed on one side of the oven at the same distance from the oven inlet, the burner 2a1 is placed in the upper part, the burner 2b1 is placed in the lower part.
  • Two other burners 2c1, 2d1 are placed on the opposite side of the oven and opposite.
  • the burner 2c1 is facing the burner 2a1, the burner 2d1 is facing the burner 2b1.
  • FIG. 7 can see the cross section of the furnace shown in Fig.6 at the first burners.
  • the burners 2a1 and 2c1 are above the products to be heated at the same height H1, the burners 2b1 and 2d1 are placed below the products to be heated at the same height H2.
  • the pressure in the furnace varies from the furnace inlet according to FIG. 8. It can be seen that this configuration makes it possible to limit the pressure at the inlet of the oven to approximately 2 Pa. Moreover, the pressure difference between the charging and the second part of the oven remains limited to approximately 17 Pa with a depression. in the second part of the oven around -15 Pa.
  • the invention mainly consists of a device which makes it possible to limit the escape of combustion fumes to the outside of a continuous furnace for heating steel products and in particular slabs, in particular slats.
  • a tunnel oven at the opening at the entrance of the furnace, characterized in that the first row of burners is composed of at least one pair of burners placed on each side of the furnace, above products to be heated, facing the same distance from the oven inlet and close to the oven inlet, and in that the burners of the first row of burners are inclined mainly from an angle A to the furnace outlet, relative to the transverse plane perpendicular to the longitudinal axis of the furnace.
  • the distance from the furnace inlet to which the first row of burners is placed is between 0.3 and 1.5 m. This distance is preferably less than the inner half-width of the oven.
  • the angle A of inclination of the burners, with respect to a direction orthogonal to the side walls, is advantageously between 10 and 45 degrees.
  • the first row of burners may comprise at least four burners divided into two pairs of two burners, one placed above the products to be heated with each burner at the same height H1, the second below the products to be heated with each burner at the same height H2.
  • FIG. 1 is an example of a tunnel oven according to the state of the art
  • FIG. 2 is an example of implantation of the burners on the first heating zone according to the state of the art
  • Fig. 3 is a graphical representation of the furnace pressure in the furnace length according to the state of the art shown in FIG. 1 and 2,
  • Fig. 4 is a second example of a tunnel oven according to the state of the art comprising an additional draw of the fumes at the entrance of the oven
  • Fig. 5 is a graphical representation of the furnace pressure in the furnace length according to the state of the art shown in FIG. 4
  • FIG. 6 is another example of implantation of the burners on the first heating zone according to the state of the art
  • FIG. 7 is a transverse view of the oven according to the state of the art shown in FIG. 6 at the first row of burner
  • Fig. 8 is a graphical representation of the furnace pressure in the furnace length according to the state of the art shown in FIG. 6 and 7,
  • Fig. 9 is a top view of the oven inlet according to an exemplary embodiment of the invention.
  • Fig. 10 is a graphical representation of furnace pressure in furnace length according to the exemplary embodiment of the invention shown in FIG.
  • FIG. 11 is a front view of the oven inlet
  • FIG. 12 is a graphical representation of furnace pressure in furnace length according to the exemplary embodiment of the invention without bottom burners 2b and 2d.
  • FIG. 9 one can see a top view of the entrance of a furnace according to an exemplary embodiment of the invention.
  • Four first burners 2a, 2b, 2c and 2d are placed at the same distance D of the oven inlet, namely two burners on each side of the oven.
  • the axes of the burners are inclined at an angle A to the furnace outlet relative to the transverse plane perpendicular to the longitudinal axis of the furnace.
  • Two burners 2a and 2c are located above the products to be heated and two burners 2b and 2d below the products to be heated.
  • the distance D between the inlet of the furnace and the first row of burners is considered hereinafter as that between the inlet of the furnace, that is to say the outer face of the sheet metal furnace perpendicular to the axis longitudinal axis of the furnace, and the transverse theoretical plane to the furnace passing through the intersection of the axes of the burners with the outer surface of the sheet metal furnace.
  • the particular implementation of these first burners according to the invention makes it possible to create a curtain consisting of the flames and the products of combustion of these burners.
  • This curtain acts as a dam and prevents the ambient air from entering the oven.
  • the inclination of the burners towards the exit of the furnace according to the invention allows a flow of the combustion fumes towards the furnace outlet and thus avoids the fumes exhaust in opposite directions, by the entrance of the furnace.
  • the inclination of the burners towards the exit of the oven is limited so as to avoid a draft and the entry of ambient air into the oven.
  • the opening 6 (Fig.11) in the oven for the entry of products 5 into the oven is greater above than below the products.
  • the products circulating on rollers, the underside of the products is always at the same height.
  • the upper surface of the products is at a variable height depending on the thickness of the products.
  • the unit heating power of the burners 2a and 2c can be increased with respect to a solution also comprising the two lower burners 2b and 2d so as to maintain the inlet of the oven at the required temperature.
  • Fig. 10 is a graph showing the variation of the pressure in the furnace according to the exemplary embodiment of the invention shown in FIG. 9, with four burners on the first row of burners.
  • Fig. 12 is a curve which shows the variation of the pressure in the oven according to the other embodiment of the invention without the burners 2b and 2d placed beneath the products to be heated.
  • the invention makes it possible to obtain a similar pressure. of the atmospheric pressure at the entrance of the oven thus avoiding the escape of the fumes outside the oven and a pressure positive just after entering the oven to help prevent air from entering the oven.
  • the higher pressure just after the inlet of the furnace as seen in Fig. 12 with respect to Fig. 10 is related to the fact that in the case of Fig. 12, the upper burners 2a and 2c have a greater power compared to the case of FIG. 10 because of the absence of the lower burners 2b and 2d.
  • the solution chosen according to the invention also makes it possible to limit the pressure difference over the length of the furnace and the vacuum in the second part of the furnace thus avoiding the aspiration of the fumes from the zones situated downstream of the latter.
  • the position of the burners of the first row with respect to the entrance of the oven and with respect to the products to be heated, the unit power of these burners and the inclination of the burners towards the exit of the oven are defined according to the geometrical characteristics of the laboratory (dimensions, position of the flue gas outlet (s)), combustion characteristics at the burners of this first row and those of the burners of the first heating zones (fuel type, air factor, air / gas flow rates, temperatures air and gas), so as to obtain the desired effect.
  • These parameters are for example obtained from a CFD modeling calculation of the furnace solving the equations of fluid mechanics (conservation of the mass, NAVIER STOKES equations and turbulence modeling).
  • the burners of the first row are four in number, two burners are implanted in screws to screw on each side of the oven above and below the products to be heated; the burners are located 0.7 m from the entrance of the oven, they have a unit power of 620 kW, the axis of the upper burners is 575 mm above the transverse axis located at mid-height of the oven, the bottom burner axis is 695 mm below this transverse axis at mid-height of the furnace, and the burner inclination angle A is 30 degrees toward the furnace outlet.
  • the distance D from the furnace inlet of the sloped burners of the first row of burners is, according to the dimensions of the furnace, between 0.3 and 1.5 meters. This distance should not be too low not to generate air intake in the oven. It should not be too big to maintain an effective curtain effect. It is for example equal to or less than the half-interior width of the oven.
  • the angle A of inclination of the burners is, according to the dimensions of the oven, between 10 and 45 degrees.
  • the burners 2a, 2b, 2c, 2d of the first row of burners operate at fixed speed and at nominal power.
  • the operating power of these burners is thus kept constant while that of the other burners 2 varies according to the heat requirement of the furnace.
  • the inclined burners of the first row of burners are according to the invention identical to those located in the first heating zone, or may be of a different power.
  • the inclination of the burners according to the invention is mainly carried out towards the furnace outlet.
  • An inclination of the burners in the first row to the top or the bottom of the oven such as for example a few degrees to the top of the oven for the burners of the first row located above the products and an inclination of a few degrees downwards of the furnace of the first row of burners located below the products can be realized but is not necessary according to the invention.

Abstract

The invention relates to a device for limiting the combustion fume exhaust towards the outside of a continuous furnace, especially a tunnel furnace, for reheating iron and steel products, especially slabs, at the opening located at the entrance of the furnace. The first row of burners consists of at least two burners (2a, 2c) arranged at the same distance (D) from the entrance of the furnace and close thereto, and the burners of the first row of burners are inclined mainly from an angle A towards the discharge area of the furnace.

Description

DISPOSITIF PERMETTANT DE LIMITER L'ECHAPPEMENT DE FUMEES DE COMBUSTION A L'ENTREE D'UN FOUR DE RECHAUFFAGE DE PRODUITS SIDERURGIQUES DEVICE FOR LIMITING THE EXHAUST OF COMBUSTION FUME AT THE ENTRANCE OF A STEEL HEATING FURNACE
La présente invention concerne un dispositif permettant de limiter l'échappement de fumées de combustion vers l'extérieur d'un four continu de réchauffage de produits sidérurgiques et en particulier de brames, notamment d'un four tunnel, au niveau de l'ouverture située à l'entrée du four.The present invention relates to a device for limiting the exhaust of combustion fumes to the outside of a continuous furnace for heating steel products and in particular slabs, in particular a tunnel furnace, at the opening located at the entrance of the oven.
Un four tunnel a généralement son entrée ouverte en permanence pour permettre le défilement des produits en provenance par exemple de la coulée continue située en amont dans le processus d'élaboration de produits plats. La section d'entrée du four est réduite au minimum pour limiter l'échappement des fumées et le rayonnement thermique vers l'extérieur du four. Néanmoins, cela ne permet pas, selon l'état de la technique, d'éviter l'échappement des fumées par l'ouverture du four. Ce phénomène néfaste est directement lié à la surpression existante dans la première zone de chauffe du four, le carneau habituellement situé en zone d'homogénéisation ne permettant pas de tirer suffisamment de fumées. Cela engendre une dégradation des parois du four au niveau de l'enfournement et pose des problèmes aux équipements situés dans la halle au voisinage et au-dessus du four.A tunnel kiln usually has its inlet open at all times to allow the flow of products coming for example from the continuous casting upstream in the process of developing flat products. The inlet section of the oven is kept to a minimum to limit smoke exhaust and heat radiation to the outside of the oven. However, this does not allow, according to the state of the art, to avoid the escape of fumes by the opening of the oven. This harmful phenomenon is directly related to the existing overpressure in the first heating zone of the furnace, the flue usually located in the homogenization zone does not allow to draw enough fumes. This causes degradation of the oven walls at the level of charging and poses problems to the equipment located in the hall near and above the oven.
Un exemple de début de four tunnel est représenté en Fig.1 des dessins annexés. Le sens de défilement des produits à réchauffer est indiqué par les flèches placées aux deux extrémités de la partie du four représentée. A partir de l'entrée des produits, sont représentées trois zones successives de chauffage, 1a, 1b, 1c, suivies de deux zones d'homogénéisation 1d et 1e. Une cheminée 3 permet l'extraction des fumées de combustion.An example of the beginning of tunnel furnace is shown in Fig.1 of the accompanying drawings. The direction of travel of the products to be heated is indicated by the arrows placed at both ends of the portion of the furnace shown. From the product inlet are shown three successive heating zones, 1a, 1b, 1c, followed by two homogenization zones 1d and 1e. A chimney 3 allows the extraction of combustion fumes.
En se reportant à la Fig. 2 des dessins annexés, on peut voir plus en détail la première zone de chauffage 1a du four tunnel de la Fig.1. Le chauffage du four est assuré par des brûleurs 2 placés sur les parois latérales du four, en- dessous et au-dessus des produits à réchauffer. Le sens de défilement des produits à réchauffer est également indiqué par les flèches placées aux deux extrémités de la zone de chauffage. Les brûleurs sont placés en quinconce ; pour un brûleur situé en-dessous du produit sur une face du four, sur la face opposée et pour la même distance depuis l'entrée du four, le brûleur se trouve au-dessus du produit. La cheminée 3 pour l'évacuation des fumées de combustion produites par les brûleurs est dans cet exemple placée dans la deuxième zone d'égalisation 1e.Referring to FIG. 2 of the accompanying drawings, it is possible to see in more detail the first heating zone 1a of the tunnel oven of FIG. The oven is heated by burners 2 placed on the side walls of the oven, below and above the products to be heated. The direction of travel of the products to be heated is also indicated by the arrows placed at both ends of the heating zone. The burners are placed in staggered rows; for a burner located below the product on one side of the oven, on the opposite side and for the same distance from the oven inlet, the burner is above the product. The chimney 3 for the evacuation of combustion fumes produced by the burners is in this example placed in the second equalization zone 1e.
En se reportant à la Fig. 3, on peut voir une courbe montrant la variation de la pression dans le four pour l'exemple de réalisation de Fig.2. La longueur du four est indiquée en abscisse depuis l'entrée, abscisse 0 mètre, jusqu'à la fin de la seconde zone d'égalisation correspondant à l'abscisse 110 mètres. La pression dans le four est indiquée en ordonnée, la valeur zéro correspond à la pression atmosphérique régnant à l'extérieur du four, une pression positive de 5 Pa (pascals) est une pression dans le four supérieure de 5 Pa à la pression à l'extérieur du four, une pression négative de 5 Pa est une pression dans le four inférieure de 5 Pa à la pression à l'extérieur du four.Referring to FIG. 3, we can see a curve showing the variation of the pressure in the oven for the embodiment of Fig.2. The length of the oven is indicated on the abscissa from the entry, abscissa 0 meter, until the end of the second equalization zone corresponding to the abscissa 110 meters. The pressure in the furnace is indicated on the ordinate, the value zero corresponds to the atmospheric pressure prevailing outside the furnace, a positive pressure of 5 Pa (pascals) is a pressure in the furnace 5 Pa higher than the pressure at the furnace. Outside the oven, a negative pressure of 5 Pa is a pressure in the oven 5 Pa lower than the pressure outside the oven.
On constate en Fig. 3 que la pression relative à l'entrée du four est d'environ 8 Pa. Celle-ci provoque l'échappement des fumées à l'extérieur du four. De plus, on constate également en Fig. 3 que la dépression en seconde partie du four est relativement importante, de l'ordre de -25 Pa, ce qui peut entraîner une rentrée de fumées issues des zones situées en aval. La différence de pression entre l'enfournement et la seconde partie du four atteint 30 Pa.We can see in Fig. 3 that the pressure relative to the inlet of the oven is about 8 Pa. This causes the exhaust fumes outside the oven. In addition, there is also shown in FIG. 3 that the depression in the second part of the furnace is relatively large, of the order of -25 Pa, which may result in a return of fumes from the downstream areas. The pressure difference between the charging and the second part of the oven reaches 30 Pa.
Plusieurs solutions ont déjà été mises en œuvre sur les fours tunnel sans pour autant supprimer complètement l'échappement des fumées.Several solutions have already been implemented on tunnel kilns without completely eliminating the exhaust fumes.
L'une des solutions mise en œuvre selon l'état de la technique consiste à améliorer le tirage des fumées par une augmentation des dimensions des carneaux. Une autre solution selon l'état de la technique consiste en l'ajout d'un second tirage des fumées en entrée de four. La Fig. 4 représente un exemple de réalisation de ce type, le second tirage des fumées en entrée de four portant le repère 4.One of the solutions implemented according to the state of the art is to improve the flue gas draft by increasing the dimensions of flues. Another solution according to the state of the art is the addition of a second draw fumes at the entrance of the oven. Fig. 4 represents an example embodiment of this type, the second draw of the fumes at the furnace inlet bearing the mark 4.
Pour cet exemple de réalisation, la pression dans le four varie depuis l'entrée du four selon la Fig. 5. On constate que l'ajout d'un second tirage des fumées en entrée de four permet d'obtenir une pression plus uniforme sur la longueur du four, avec une différence de pression entre l'enfournement et le reste du four limitée à environ 15 Pa du fait que la pression est remontée dans la seconde partie du four pour atteindre une valeur de -10 Pa. Cependant, la surpression à l'entrée du four tunnel n'a pas été atténuée et le risque d'échappement des fumées persiste. Par ailleurs, l'ajout de ce second tirage des fumées en entrée de four entraîne un surcoût important du fait de cet équipement supplémentaire.For this exemplary embodiment, the pressure in the oven varies from the inlet of the oven according to FIG. 5. It is found that the addition of a second draft of the fumes at the entrance of the oven makes it possible to obtain a more uniform pressure over the length of the oven, with a pressure difference between the charging and the rest of the oven limited to about 15 Pa because the pressure is raised in the second part of the furnace to reach a value of -10 Pa. However, the overpressure at the entrance of the tunnel kiln has not been attenuated and the risk of smoke escaping persists. Furthermore, the addition of this second draw fumes at the entrance of the oven leads to significant additional cost because of this additional equipment.
Une autre solution selon l'état de la technique consiste à rapprocher la première rangée de brûleurs de l'entrée du four. Une variante de cette configuration représentée en Fig. 6 et en Fig. 7 consiste à placer deux brûleurs 2a1,2b1; 2c1 ,2d1 sur chaque face du four, en-dessous et au-dessus du produit à réchauffer de manière à avoir deux paires de brûleurs en vis-à-vis. Deux brûleurs 2a1 et 2b1 sont placés sur l'un des côtés du four à une même distance de l'entrée du four, le brûleur 2a1 est placé en partie supérieure, le brûleur 2b1 est placé en partie inférieure. Deux autres brûleurs 2c1, 2d1 sont placés sur le côté opposé du four et en vis à vis. Le brûleur 2c1 se trouve face au brûleur 2a1 , le brûleur 2d1 se trouve face au brûleur 2b1.Another solution according to the state of the art is to bring the first row of burners from the entrance of the oven. A variant of this configuration shown in FIG. 6 and in FIG. 7 consists in placing two burners 2a1,2b1; 2c1, 2d1 on each side of the oven, below and above the product to be heated so as to have two pairs of burners vis-à-vis. Two burners 2a1 and 2b1 are placed on one side of the oven at the same distance from the oven inlet, the burner 2a1 is placed in the upper part, the burner 2b1 is placed in the lower part. Two other burners 2c1, 2d1 are placed on the opposite side of the oven and opposite. The burner 2c1 is facing the burner 2a1, the burner 2d1 is facing the burner 2b1.
En se reportant à la Fig. 7 ont peut voir la coupe transversale du four représentée en Fig.6 au niveau des premiers brûleurs. Les brûleurs 2a1 et 2c1 sont au-dessus des produits à réchauffer à une même hauteur H1 , les brûleurs 2b1 et 2d1 sont placés en-dessous des produits à réchauffer à une même hauteur H2.Referring to FIG. 7 can see the cross section of the furnace shown in Fig.6 at the first burners. The burners 2a1 and 2c1 are above the products to be heated at the same height H1, the burners 2b1 and 2d1 are placed below the products to be heated at the same height H2.
Pour cet exemple de réalisation des Fig.6 et 7, la pression dans le four varie depuis l'entrée du four selon la Fig. 8. On constate que cette configuration permet de limiter la pression à l'entrée du four à environ 2 Pa. De plus, l'écart de pression entre l'enfournement et la seconde partie du four reste limité à environ 17 Pa avec une dépression dans la seconde partie du four autour de -15 Pa.For this embodiment of Fig.6 and 7, the pressure in the furnace varies from the furnace inlet according to FIG. 8. It can be seen that this configuration makes it possible to limit the pressure at the inlet of the oven to approximately 2 Pa. Moreover, the pressure difference between the charging and the second part of the oven remains limited to approximately 17 Pa with a depression. in the second part of the oven around -15 Pa.
Cependant, la pression est négative tout au long du four, notamment juste après l'entrée, ce qui peut engendrer des entrées d'air dans le four. Celles-ci auraient pour effet d'augmenter la consommation énergétique du four et de modifier la teneur en oxygène en entrée de four ce qui pourrait conduire à une augmentation de l'oxydation des produits à réchauffer.However, the pressure is negative throughout the oven, especially just after entry, which can cause air in the oven. These would have the effect of increasing the energy consumption of the oven and change the oxygen content at the entrance of the oven which could lead to an increase in the oxidation of the products to be heated.
Comme exposé précédemment, les solutions mises en œuvre selon l'état de la technique ne donnent pas pleinement satisfaction. Pour apporter une solution à ce problème, l'invention consiste principalement en un dispositif qui permet de limiter l'échappement de fumées de combustion vers l'extérieur d'un four continu de réchauffage de produits sidérurgiques et en particulier de brames, notamment d'un four tunnel, au niveau de l'ouverture située à l'entrée du four, et qui est caractérisé en ce que la première rangée de brûleurs est composée d'au moins une paire de brûleurs placés de chaque côté du four, au-dessus des produits à réchauffer, en vis à vis à une même distance de l'entrée du four et à proximité de l'entrée du four, et en ce que les brûleurs de la première rangée de brûleurs sont inclinés principalement d'un angle A vers la sortie du four, par rapport au plan transversal perpendiculaire à l'axe longitudinal du four.As explained above, the solutions implemented according to the state of the art do not give full satisfaction. To provide a solution to this problem, the invention mainly consists of a device which makes it possible to limit the escape of combustion fumes to the outside of a continuous furnace for heating steel products and in particular slabs, in particular slats. a tunnel oven, at the opening at the entrance of the furnace, characterized in that the first row of burners is composed of at least one pair of burners placed on each side of the furnace, above products to be heated, facing the same distance from the oven inlet and close to the oven inlet, and in that the burners of the first row of burners are inclined mainly from an angle A to the furnace outlet, relative to the transverse plane perpendicular to the longitudinal axis of the furnace.
Avantageusement, la distance de l'entrée du four à laquelle est placée la première rangée de brûleurs est comprise entre 0.3 et 1.5 m. Cette distance est de préférence inférieure à la demi-largeur intérieure du four.Advantageously, the distance from the furnace inlet to which the first row of burners is placed is between 0.3 and 1.5 m. This distance is preferably less than the inner half-width of the oven.
L'angle A d'inclinaison des brûleurs, par rapport à une direction orthogonale aux parois latérales, est avantageusement compris entre 10 et 45 degrés.The angle A of inclination of the burners, with respect to a direction orthogonal to the side walls, is advantageously between 10 and 45 degrees.
La première rangée de brûleurs peut comprendre au moins quatre brûleurs répartis en deux paires de deux brûleurs, l'une placée au-dessus des produits à réchauffer avec chaque brûleur à une même hauteur H1, la seconde en- dessous des produits à réchauffer avec chaque brûleur à une même hauteur H2.The first row of burners may comprise at least four burners divided into two pairs of two burners, one placed above the products to be heated with each burner at the same height H1, the second below the products to be heated with each burner at the same height H2.
L'invention consiste, mises à part les dispositions exposées ci-dessus, en un certain nombre d'autres dispositions dont il sera plus explicitement question ci- après à propos d'exemples de réalisation décrits avec référence aux dessins annexés, mais qui ne sont nullement limitatifs. Sur ces dessins :The invention consists, apart from the arrangements described above, in a certain number of other arrangements which will be more explicitly discussed below with regard to embodiments described with reference to the accompanying drawings, but which are not in no way limiting. On these drawings:
Fig. 1 est un exemple de four tunnel selon l'état de la technique, Fig. 2 est un exemple d'implantation des brûleurs sur la première zone de chauffage selon l'état de la technique,Fig. 1 is an example of a tunnel oven according to the state of the art, FIG. 2 is an example of implantation of the burners on the first heating zone according to the state of the art,
Fig. 3 est une représentation graphique de la pression du four dans la longueur du four selon l'état de la technique représenté en Fig. 1 et 2,Fig. 3 is a graphical representation of the furnace pressure in the furnace length according to the state of the art shown in FIG. 1 and 2,
Fig. 4 est un second exemple de four tunnel selon l'état de la technique comprenant un tirage supplémentaire des fumées à l'entrée du four, Fig. 5 est une représentation graphique de la pression du four dans la longueur du four selon l'état de la technique représenté en Fig. 4,Fig. 4 is a second example of a tunnel oven according to the state of the art comprising an additional draw of the fumes at the entrance of the oven, Fig. 5 is a graphical representation of the furnace pressure in the furnace length according to the state of the art shown in FIG. 4
Fig. 6 est un autre exemple d'implantation des brûleurs sur la première zone de chauffage selon l'état de la technique, Fig. 7 est une vue transversale du four selon l'état de la technique représenté en Fig. 6 au niveau de la première rangée de brûleur,Fig. 6 is another example of implantation of the burners on the first heating zone according to the state of the art, FIG. 7 is a transverse view of the oven according to the state of the art shown in FIG. 6 at the first row of burner,
Fig. 8 est une représentation graphique de la pression du four dans la longueur du four selon l'état de la technique représenté en Fig. 6 et 7,Fig. 8 is a graphical representation of the furnace pressure in the furnace length according to the state of the art shown in FIG. 6 and 7,
Fig. 9 est une vue de dessus de l'entrée du four selon un exemple de réalisation de l'invention,Fig. 9 is a top view of the oven inlet according to an exemplary embodiment of the invention,
Fig. 10 est une représentation graphique de la pression du four dans la longueur du four selon l'exemple de réalisation de l'invention représenté en Fig.Fig. 10 is a graphical representation of furnace pressure in furnace length according to the exemplary embodiment of the invention shown in FIG.
9.9.
Fig. 11 est une vue de face de l'entrée du four, et Fig. 12 est une représentation graphique de la pression du four dans la longueur du four selon l'exemple de réalisation de l'invention sans les brûleurs inférieurs 2b et 2d.Fig. 11 is a front view of the oven inlet, and FIG. 12 is a graphical representation of furnace pressure in furnace length according to the exemplary embodiment of the invention without bottom burners 2b and 2d.
Les Fig.1 à 8 des dessins, relatives à l'état de la technique, ont été décrites précédemment.Figures 1 to 8 of the drawings, relating to the state of the art, have been described previously.
En se reportant à la Fig. 9, on peut voir une vue de dessus de l'entrée d'un four selon un exemple de réalisation de l'invention. Quatre premiers brûleurs 2a, 2b, 2c et 2d , sont placés à une même distance D de l'entrée du four, à savoir deux brûleurs de chaque côté du four. Les axes des brûleurs sont inclinés d'un angle A vers la sortie du four par rapport au plan transversal perpendiculaire à l'axe longitudinal du four. Deux brûleurs 2a et 2c sont situés au-dessus des produits à réchauffer et deux brûleurs 2b et 2d en-dessous des produits à réchauffer.Referring to FIG. 9, one can see a top view of the entrance of a furnace according to an exemplary embodiment of the invention. Four first burners 2a, 2b, 2c and 2d, are placed at the same distance D of the oven inlet, namely two burners on each side of the oven. The axes of the burners are inclined at an angle A to the furnace outlet relative to the transverse plane perpendicular to the longitudinal axis of the furnace. Two burners 2a and 2c are located above the products to be heated and two burners 2b and 2d below the products to be heated.
Comme représenté en Fig. 9, la distance D entre l'entrée du four et la première rangée de brûleurs est considérée ci-après comme étant celle entre l'entrée du four, c'est à dire la face extérieure de la tôlerie du four perpendiculaire à l'axe longitudinal du four, et le plan théorique transversal au four passant par l'intersection des axes des brûleurs avec la surface extérieure de la tôlerie du four.As shown in FIG. 9, the distance D between the inlet of the furnace and the first row of burners is considered hereinafter as that between the inlet of the furnace, that is to say the outer face of the sheet metal furnace perpendicular to the axis longitudinal axis of the furnace, and the transverse theoretical plane to the furnace passing through the intersection of the axes of the burners with the outer surface of the sheet metal furnace.
L'implantation particulière de ces premiers brûleurs selon l'invention permet de créer un rideau constitué des flammes et des produits de combustion de ces brûleurs. Ce rideau fait office de barrage et permet d'éviter que l'air ambiant n'entre dans le four. L'inclinaison des brûleurs vers la sortie du four selon l'invention permet un écoulement des fumées de combustion vers la sortie du four et évite ainsi les échappements de fumées en sens opposé, par l'entrée du four. L'inclinaison des brûleurs vers la sortie du four est limitée de sorte d'éviter un appel d'air et l'entrée d'air ambiant dans le four.The particular implementation of these first burners according to the invention makes it possible to create a curtain consisting of the flames and the products of combustion of these burners. This curtain acts as a dam and prevents the ambient air from entering the oven. The inclination of the burners towards the exit of the furnace according to the invention allows a flow of the combustion fumes towards the furnace outlet and thus avoids the fumes exhaust in opposite directions, by the entrance of the furnace. The inclination of the burners towards the exit of the oven is limited so as to avoid a draft and the entry of ambient air into the oven.
Les brûleurs 2 suivants restent perpendiculaires à l'axe longitudinal du four.The following burners 2 remain perpendicular to the longitudinal axis of the furnace.
L'ouverture 6 (Fig.11) dans le four destinée à l'entrée des produits 5 dans le four est plus importante au-dessus qu'en-dessous des produits. Les produits circulant sur des rouleaux, la face inférieure des produits se trouve toujours à la même hauteur. Par contre la face supérieure des produits se trouve à une hauteur variable selon l'épaisseur des produits. De ce fait, l'ouverture dans le four peut être réduite en-dessous des produits pour éviter les sorties de fumées ou les entrées d'air, mais doit être plus importante au-dessus des produits pour permettre le passage du produit le plus épais.The opening 6 (Fig.11) in the oven for the entry of products 5 into the oven is greater above than below the products. The products circulating on rollers, the underside of the products is always at the same height. On the other hand, the upper surface of the products is at a variable height depending on the thickness of the products. As a result, the opening in the furnace can be reduced below the products to avoid smoke exits or air inlets, but must be greater above the products to allow the passage of the thickest product. .
Selon un autre exemple de réalisation de l'invention, du fait d'une ouverture réduite du four sous les produits à réchauffer, les deux brûleurs inférieurs 2b etAccording to another embodiment of the invention, because of a reduced opening of the oven under the products to be heated, the two lower burners 2b and
2d placés en-dessous des produits à réchauffer ne sont pas nécessaires. Dans cette configuration, la puissance calorifique unitaire des brûleurs 2a et 2c peut être augmentée par rapport à une solution comprenant également les deux brûleurs inférieurs 2b et 2d de sorte de maintenir l'entrée du four à la température requise.2d placed below the products to be heated are not necessary. In this configuration, the unit heating power of the burners 2a and 2c can be increased with respect to a solution also comprising the two lower burners 2b and 2d so as to maintain the inlet of the oven at the required temperature.
La Fig. 10 est une courbe qui montre la variation de la pression dans le four selon l'exemple de réalisation de l'invention représenté en Fig. 9, avec quatre brûleurs sur la première rangée de brûleurs. La Fig. 12 est une courbe qui montre la variation de la pression dans le four selon l'autre exemple de réalisation de l'invention sans les brûleurs 2b et 2d placés en-dessous des produits à réchauffer.Fig. 10 is a graph showing the variation of the pressure in the furnace according to the exemplary embodiment of the invention shown in FIG. 9, with four burners on the first row of burners. Fig. 12 is a curve which shows the variation of the pressure in the oven according to the other embodiment of the invention without the burners 2b and 2d placed beneath the products to be heated.
Comme on peut le voir sur la Fig.10 correspondant à quatre brûleurs sur la première rangée de brûleurs, et sur la Fig.12 correspondant uniquement aux deux brûleurs supérieurs sur la première rangée de brûleurs, l'invention permet d'obtenir une pression voisine de la pression atmosphérique à l'entrée du four évitant ainsi l'échappement des fumées à l'extérieur du four et une pression positive juste après l'entrée du four contribuant à éviter les entrées d'air à l'intérieur du four.As can be seen in FIG. 10 corresponding to four burners on the first row of burners, and in FIG. 12 corresponding only to the two upper burners on the first row of burners, the invention makes it possible to obtain a similar pressure. of the atmospheric pressure at the entrance of the oven thus avoiding the escape of the fumes outside the oven and a pressure positive just after entering the oven to help prevent air from entering the oven.
La pression plus importante juste après l'entrée du four que l'on observe sur la Fig.12 par rapport à la Fig.10 est liée au fait que, dans le cas de la Fig. 12, les brûleurs supérieurs 2a et 2c ont une puissance plus importante par rapport au cas de la Fig. 10 du fait de l'absence des brûleurs inférieurs 2b et 2d.The higher pressure just after the inlet of the furnace as seen in Fig. 12 with respect to Fig. 10 is related to the fact that in the case of Fig. 12, the upper burners 2a and 2c have a greater power compared to the case of FIG. 10 because of the absence of the lower burners 2b and 2d.
La solution retenue selon l'invention permet également de limiter la différence de pression sur la longueur du four et la dépression dans la seconde partie du four évitant ainsi l'aspiration des fumées des zones situées en aval de celle-ci.The solution chosen according to the invention also makes it possible to limit the pressure difference over the length of the furnace and the vacuum in the second part of the furnace thus avoiding the aspiration of the fumes from the zones situated downstream of the latter.
La position des brûleurs de la première rangée par rapport à l'entrée du four et par rapport aux produits à réchauffer, la puissance unitaire de ces brûleurs et l'inclinaison des brûleurs vers la sortie du four sont définis en fonction des caractéristiques géométriques du laboratoire (dimensions, position de la ou des sorties de fumées), des caractéristiques de la combustion aux brûleurs de cette première rangée et de celles des brûleurs des premières zones de chauffage (nature du combustible, facteur d'air, débits air/gaz, températures d'air et de gaz), de sorte d'obtenir l'effet escompté. Ces paramètres sont par exemple obtenus à partir d'un calcul de modélisation CFD du four résolvant les équations de la mécanique des fluides (conservation de la masse, équations de NAVIER STOKES et modélisation de la turbulence).The position of the burners of the first row with respect to the entrance of the oven and with respect to the products to be heated, the unit power of these burners and the inclination of the burners towards the exit of the oven are defined according to the geometrical characteristics of the laboratory (dimensions, position of the flue gas outlet (s)), combustion characteristics at the burners of this first row and those of the burners of the first heating zones (fuel type, air factor, air / gas flow rates, temperatures air and gas), so as to obtain the desired effect. These parameters are for example obtained from a CFD modeling calculation of the furnace solving the equations of fluid mechanics (conservation of the mass, NAVIER STOKES equations and turbulence modeling).
Selon un exemple de réalisation de l'invention, pour un four d'une largeur interne de 2 m et d'une hauteur interne de 2.65 m, les brûleurs de la première rangée sont au nombre de quatre, deux brûleurs sont implantés en vis à vis sur chaque côté du four au-dessus et en-dessous des produits à réchauffer ; les brûleurs sont implantés à 0.7 m de l'entrée du four, ils ont une puissance unitaire de 620 kW, l'axe des brûleurs supérieurs se trouve à 575 mm au- dessus de l'axe transversal situé à mi-hauteur du four, l'axe des brûleurs inférieurs se trouve à 695 mm au-dessous de cet axe transversal situé à mi- hauteur du four, et I' angle A d'inclinaison des brûleurs est de 30 degrés vers la sortie du four.According to an exemplary embodiment of the invention, for an oven with an internal width of 2 m and an internal height of 2.65 m, the burners of the first row are four in number, two burners are implanted in screws to screw on each side of the oven above and below the products to be heated; the burners are located 0.7 m from the entrance of the oven, they have a unit power of 620 kW, the axis of the upper burners is 575 mm above the transverse axis located at mid-height of the oven, the bottom burner axis is 695 mm below this transverse axis at mid-height of the furnace, and the burner inclination angle A is 30 degrees toward the furnace outlet.
Selon l'invention, la distance D depuis l'entrée du four des brûleurs inclinés de la première rangée de brûleurs est, selon les dimensions du four, comprise entre 0.3 et 1.5 mètre. Cette distance ne doit pas être trop faible pour ne pas générer d'entrée d'air dans le four. Elle ne doit pas non plus être trop grande de sorte de conserver un effet de rideau efficace. Elle est par exemple égale ou inférieure à la demi-largeur intérieure du four.According to the invention, the distance D from the furnace inlet of the sloped burners of the first row of burners is, according to the dimensions of the furnace, between 0.3 and 1.5 meters. This distance should not be too low not to generate air intake in the oven. It should not be too big to maintain an effective curtain effect. It is for example equal to or less than the half-interior width of the oven.
Selon l'invention, l'angle A d'inclinaison des brûleurs est, selon les dimensions du four, compris entre 10 et 45 degrés.According to the invention, the angle A of inclination of the burners is, according to the dimensions of the oven, between 10 and 45 degrees.
Selon l'exemple préféré de réalisation de l'invention, les brûleurs 2a,2b,2c,2d de la première rangée de brûleurs fonctionnent à régime fixe et à puissance nominale. La puissance de fonctionnement de ces brûleurs est ainsi maintenue constante alors que celle des autres brûleurs 2 varie en fonction du besoin calorifique du four.According to the preferred embodiment of the invention, the burners 2a, 2b, 2c, 2d of the first row of burners operate at fixed speed and at nominal power. The operating power of these burners is thus kept constant while that of the other burners 2 varies according to the heat requirement of the furnace.
Les brûleurs inclinés de la première rangée de brûleurs sont selon l'invention identiques à ceux situés dans la première zone de chauffage, ou peuvent être d'une puissance différente.The inclined burners of the first row of burners are according to the invention identical to those located in the first heating zone, or may be of a different power.
L'inclinaison des brûleurs selon l'invention est réalisée principalement vers la sortie du four. Une inclinaison des brûleurs de la première rangée vers le haut ou le bas du four telle que par exemple de quelques degrés vers le haut du four pour les brûleurs de la première rangée situé au-dessus des produits et une inclinaison de quelques degrés vers le bas du four des brûleurs de la première rangée situé en-dessous des produits peut être réalisée mais n'est pas nécessaire selon l'invention. The inclination of the burners according to the invention is mainly carried out towards the furnace outlet. An inclination of the burners in the first row to the top or the bottom of the oven such as for example a few degrees to the top of the oven for the burners of the first row located above the products and an inclination of a few degrees downwards of the furnace of the first row of burners located below the products can be realized but is not necessary according to the invention.

Claims

REVENDICATIONS
1. Dispositif permettant de limiter l'échappement de fumées de combustion vers l'extérieur d'un four continu de réchauffage de produits sidérurgiques et en particulier de brames, notamment d'un four tunnel, au niveau de l'ouverture située à l'entrée du four, caractérisé en ce que la première rangée de brûleurs est composée d'au moins une paire de brûleurs (2a,2c) placés de chaque côté du four, au-dessus des produits à réchauffer (5), en vis à vis à une même distance (D) de l'entrée du four et à proximité de l'entrée du four et en ce que les brûleurs (2a,2c) de la première rangée de brûleurs sont inclinés principalement d'un angle A vers la sortie du four, par rapport au plan transversal perpendiculaire à l'axe longitudinal du four.1. Device for limiting the escape of combustion fumes to the outside of a continuous heating furnace of steel products and in particular slabs, in particular of a tunnel furnace, at the opening located at the oven inlet, characterized in that the first row of burners is composed of at least one pair of burners (2a, 2c) placed on each side of the oven, above the products to be heated (5), facing each other at the same distance (D) from the furnace inlet and near the furnace inlet and in that the burners (2a, 2c) of the first row of burners are inclined mainly at an angle A to the outlet of the furnace, relative to the transverse plane perpendicular to the longitudinal axis of the furnace.
2. Dispositif selon la revendication 1 , caractérisé en ce que la distance (D) à laquelle est placée la première rangée de brûleurs de l'entrée du four est comprise entre 0.3 et 1.5 m.2. Device according to claim 1, characterized in that the distance (D) at which is placed the first row of burners of the oven inlet is between 0.3 and 1.5 m.
3. Dispositif selon la revendication 1 , caractérisé en ce que la distance (D) à laquelle est placée la première rangée de brûleurs de l'entrée du four est inférieure à la demi-largeur intérieure du four.3. Device according to claim 1, characterized in that the distance (D) at which is placed the first row of burners of the oven inlet is less than the inner half-width of the oven.
4. Dispositif selon l'une quelconque des revendications 1 à 3, caractérisé en ce que l'angle A d'inclinaison vers la sortie du four des brûleurs de la première rangée de brûleurs est compris entre 10 et 45 degrés.4. Device according to any one of claims 1 to 3, characterized in that the angle of inclination A towards the furnace outlet of the burners of the first row of burners is between 10 and 45 degrees.
5. Dispositif selon la revendication 4, caractérisé en ce que l'angle A d'inclinaison vers la sortie du four des brûleurs de la première rangée de brûleurs est de 30 degrés.5. Device according to claim 4, characterized in that the angle A of inclination towards the furnace outlet of the burners of the first row of burners is 30 degrees.
6. Dispositif selon l'une quelconque des revendications 1 à 5, caractérisé en ce que la première rangée de brûleurs comprend au moins quatre brûleurs (2a,2b,2c,2d) répartis en deux paires de deux brûleurs, l'une (2a,2c) placée au- dessus des produits à réchauffer avec chaque brûleur à une même hauteur (H1), la seconde en-dessous des produits à réchauffer avec chaque brûleur à une même hauteur (H2). 6. Device according to any one of claims 1 to 5, characterized in that the first row of burners comprises at least four burners (2a, 2b, 2c, 2d) divided into two pairs of two burners, one (2a). , 2c) placed above the products to be heated with each burner at the same height (H1), the second below the products to be heated with each burner at the same height (H2).
7. Dispositif selon l'une quelconque des revendications 1 à 6, caractérisé en ce que les brûleurs (2a,2b,2c,2d) de la première rangée de brûleurs fonctionnent à régime fixe et à puissance nominale, la puissance de fonctionnement de ces brûleurs étant ainsi maintenue constante alors que celle des autres brûleurs (2) varie en fonction du besoin calorifique du four. 7. Device according to any one of claims 1 to 6, characterized in that the burners (2a, 2b, 2c, 2d) of the first row of burners operate at fixed speed and nominal power, the operating power of these The burners are thus kept constant while that of the other burners (2) varies according to the heat requirement of the furnace.
PCT/FR2008/000869 2007-06-21 2008-06-20 Device for limiting the combustion fume exhaust at the entrance of a furnace for reheating iron and steel products WO2009013410A2 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
BRPI0813401-4A2A BRPI0813401A2 (en) 2007-06-21 2008-06-20 DEVICE ALLOWING TO LIMIT EXHAUST OF COMBUSTION SMOKE TO THE OUTSIDE OF A CONTINUOUS HEATING PRODUCT OVEN.
EP08826510A EP2156125A2 (en) 2007-06-21 2008-06-20 Device for limiting the combustion fume exhaust at the entrance of a furnace for reheating iron and steel products
US12/664,188 US20100183992A1 (en) 2007-06-21 2008-06-20 Device for limiting the exhausting of combustion flue gases at the inlet of a furnace for reheating steel products

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR0704434 2007-06-21
FR0704434A FR2917817B1 (en) 2007-06-21 2007-06-21 DEVICE FOR LIMITING THE EXHAUST OF COMBUSTION FUME AT THE ENTRANCE OF A STEEL HEATING FURNACE

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WO2009013410A2 true WO2009013410A2 (en) 2009-01-29
WO2009013410A3 WO2009013410A3 (en) 2009-03-19

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EP (1) EP2156125A2 (en)
BR (1) BRPI0813401A2 (en)
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WO (1) WO2009013410A2 (en)

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BE1021965B1 (en) * 2013-07-19 2016-01-29 Fib Belgium METHOD AND DEVICE FOR THERMALLY PROCESSING METALLIC WIRES

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JP2006274432A (en) * 2005-03-30 2006-10-12 Osaka Gas Co Ltd Continuous annealing furnace equipped with alternate regeneration burner

Also Published As

Publication number Publication date
BRPI0813401A2 (en) 2014-12-30
FR2917817A1 (en) 2008-12-26
US20100183992A1 (en) 2010-07-22
EP2156125A2 (en) 2010-02-24
WO2009013410A3 (en) 2009-03-19
FR2917817B1 (en) 2016-05-27

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