LU83275A1 - IMPROVEMENTS IN LIQUID CIRCULATING HEAT EXCHANGING DEVICES FOR COOLING WALL FURNACES - Google Patents

Description

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The invention relates to improvements made to heat exchange devices used for cooling a wall of a blast furnace and comprising a closed enclosure having a shape general flattened 5 (its thickness being small with respect to its diameter) and substantially of revolution around an axis of revolution, a coolant being circulated in said enclosure, these improvements adding to those already provided to these devices by the princi-10 pal patent.

It will first be recalled that heat exchange devices of the aforementioned kind (commonly referred to as "cooling plates" in this technique) are intended to be placed, in the most exposed parts of the blast furnace, between the metal shielding of a blast furnace and the interior wall of refractory material, in order to prevent the (shielding from overheating. Other heat exchange devices of the aforementioned kind (commonly called "re-20 boxes flat cooling "or" flat boxes ") are intended to be arranged, like the normal cooling boxes, approximately perpendicular to the wall of the blast furnace and penetrate into the refractory material which they mechanically support and which they re-25 so as to prevent its deterioration too quickly under the action of heat.

It will also be recalled that the above improvements described in the main patent consisted essentially in providing: 30 - injection means, for injecting with a tangential component the coolant, located in a first region of the enclosure, - and evacuation means, for evacuating this liquid tangentially, located in a second region of h 2 the enclosure, said liquid injection and evacuation means being respectively spaced radially from each other, said enclosure and said means for injecting and discharging the liquid being arranged so that any point situated inside the enclosure encounters no obstacle during a rotational movement around the axis of revolution .

These heat exchange devices of the cooling plate type have proved to be particularly interesting, given their extreme constructive simplicity and therefore their lower cost price.

The object of the invention is to specify certain specific provisions applicable to the above-mentioned cooling devices in order to make them suitable for particular applications.

To do this, in a first embodiment, it is envisaged that, the means of tangential injection of; liquid opening tangentially into the enclosure on the periphery or in the vicinity of the periphery thereof and the means for tangential discharge of the liquid being located in the center of the enclosure, the tangential discharge means comprise at least one set deflector means located in the center of the enclosure and a conduit opening into one face of the enclosure opposite said deflector means.

Thanks to the presence of the deflector means, it facilitates the recovery of the coolant in its spiral rotation movement and its supply to the orifice of the discharge duct. This recovery takes place more quickly, which further improves the flow rate of the liquid and allows more efficient cooling of the walls of the enclosure.

The exhaust duct can be arranged to extend radially from the center of the enclosure to the periphery of the enclosure.

In order not to increase the thickness of the heat exchange device, it is advantageous that the radial evacuation duct is inside the enclosure, that it

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3 * ”extends substantially equidistant from the two side walls of the enclosure and that two sets of deflector means are provided on either side of said conduit. Preferably, the radial evacuation duct is then profiled externally to offer minimum resistance to the liquid in rotation in the enclosure.

Advantageously, the radial evacuation conduit opens into a transit chamber, external to the enclosure and comprising a water outlet orifice.

10 Another provision, which is used either in combination with one or the other of the preceding, or in combination with the improvements of the main patent, is that the tangential evacuation means comprise a through duct tangentially in the enclosure, at the periphery thereof, the orifice of said conduit being diametrically opposite to the orifice of the tangential injection means.

In another embodiment of the invention, it is envisaged that, the tangential injection means opening out into the central part of the enclosure and the tangential evacuation means being located at the periphery of the enclosure, the tangential injection means comprise at least one liquid supply conduit opening into at least one face of the enclosure and substantially at the center of said face and at least one set of means; deflectors located opposite the orifice of said conduit, to impart a component of force tangential to the liquid opening into the enclosure.

The flat cooling boxes used to date are in a generally flattened, substantially parallelepipedic shape, the rear part of which is provided with means of attachment to the shield and the front part (or nose) of which is constituted by a flat face which is connected with a small radius on the lateral faces.

To bring the coolant to circulate in the nose, there is provided, inside the enclosure thus formed, at least one separating wall forcing the liquid to follow the outer wall of the box.

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However, in 90 ° elbows, the speed of the veins of the liquid - which are located * outermost (that is to say, even in contact with the wall of the box) - greatly decreases; it follows that this elbow area 5 is poorly cooled while the nose is precisely the part of the box which is most exposed to heat.

In addition, this decrease in speed of the liquid can be such that a recirculation, or dead water zone, is created in the elbow favoring the settling of particu-10 the solids which slow down the heat exchange. The wall of the enclosure heats up, which further increases scaling, which further curbs heat exchange.

• This cumulative phenomenon gradually gains and the box eventually perishes under the action of ther-15 momechanical abrasion, because the copper (of which these boxes are generally made) poorly cooled loses all its mechanical characteristics and is very easily worn, not only by charges, but also by hot gases, dust charges, etc.

20 As for the veins of liquid which are killed the most inside the elbow (in contact with the internal separating wall), their speed is greatly increased, which can lead to very high speeds of the liquid if the flow was increased to improve the cooling of the plate.

The effects of this high speed of circulation of the liquid are even more harmful than in the previous case because, in this region where the liquid undergoes a change in trajectory of 180 °, there is a cavitation causing a pressure drop and causing rapid wear of the separating wall.

Furthermore, the increase in the speed of the coolant can, in a practical manner, only be obtained by a reduction in the cross section of the conduits, which results in a decrease in the volume of liquid and therefore of the flywheel. thermal.

Finally, these boxes are difficult to produce and therefore costly.

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The implementation of the arrangements according to the invention to constitute a flat cooling box * makes it possible to produce an enclosure which does not have any elbow with a small radius of curvature and in which the veins 5 of liquid follow trajectories of radius sufficiently large to avoid the creation of the above-mentioned dead zones; furthermore, there is no part capable of causing cavitation. The deposits of solid particles are therefore removed and no region of the box is subjected to particular destructive wear.

Furthermore, it will be noted that it is the entire mass of coolant which is set in free rotation inside the enclosure and that all this mass participates at all times in the cooling of the walls. This results in a considerably increased cooling efficiency compared to what has been obtained hitherto.

Finally, the manufacture of flat boxes thus arranged 20 proves to be simpler, and therefore less expensive than that of known flat boxes.

In a preferred embodiment, connection means are arranged side by side and connected to the enclosure by means of conduits which extend between two planes containing the coolants. two substantially parallel faces of the enclosure.

Finally, an additional arrangement, more particularly advantageous in the case where the thermal exchange device is intended to be used as a cooling box, consists in providing a second enclosure covering at least the front part of the first enclosure. , no communication for the coolant existing between the first and secon-35 of enclosure.

The addition of this second enclosure considerably increases the efficiency of the heat exchange device of the invention for a general space requirement of just 6 times greater.

In addition, by circulating the coolant in opposite directions in the two enclosures, a better distributed and more regular cooling is obtained over the entire periphery of the device since to a region of an enclosure traversed by heated liquid corresponds a region of the other enclosure traversed by still cold liquid.

The arrangements of the invention find a second application in so-called "vaporization" cooling boxes in which vapor bubbles are formed in contact with the hot walls.

This type of box is arranged so that the vapor bubbles are collected, by gravity, in the duct 15 for discharging the coolant.

The major drawback of the spray boxes currently used is that the heat is dissipated essentially by convection. In the event of brutal thermal aggression in a determined zone of the box, this thermal inflow can be all the less efficiently evacuated as there is generally no pump in the circuit and as the circulation of the coolant occurs naturally by thermosyphon phenomenon. This results in a phenomenon of heat build-up in the area considered, causing in the conduits the formation of an interrupting vapor plug, and even capable of sometimes reversing the natural circulation of the coolant. Uncooled, the box is quickly destroyed.

On the contrary, in a cooling box arranged in accordance with the invention, the vapor bubbles are subjected to the action of centrifugal force due to the rotation of the mass of liquid. Thus, due to the existence of this gravitational field, the vapor bubbles are torn from the wall as they are created and are entrained towards the center of the box.

In a cooling box arranged in accordance with the above arrangements, it is provided that the radial duct, extending from the central zone of the box up to the rear of the box, is located in the upper part of the box (in the mounting position thereof), and preferably outside the enclosure, so as to form a recovery chamber for the water-va-fear emulsion which is then evacuated.

The arrangements of the invention find a third application in cooling plates.

The cooling plates currently used are in the form of rectangular metal plates traversed by a plurality of conduits intended for the circulation of the coolant. The conduits are independent of each other and each have an inlet port and an outlet port respectively provided with fixing means for connection to external hydraulic circuits. In addition, these plates include fixing means for their attachment to the shielding of the blast furnace.

Typically, a known cooling plate has up to twelve fastening points 20 either for its attachment or for its connection to the external circuits.

The very high temperatures to which the plates are exposed cause expansion which is incompatible with such a high number of rigid points and the plates are subjected to mechanical stresses such that they are quickly rendered unusable.

Furthermore, the flow rate of coolant in these known plates is too low and the thermal flywheel thus created is too small to provide effective cooling of the shield.

On the contrary, by its very design, the cooling device of the invention, due to the relatively large volume of liquid put into rotation, has a high thermal flywheel which allows cooling much higher than that obtained hitherto.

As for the problem of mechanical stresses, it is solved in a cooling device in accordance with fr 8 the invention by the fact that: - the two supply and discharge pipes for the coolant extend approximately perpendicular to that of the walls of the device which, in the mounting position in the blast furnace, is in contact with the shielding of said blast furnace, from the central region of said wall, - the two conduits are concentric, at least in the vicinity of said wall, 10 - and the means for fixing the plate to the shield include that of the aforementioned conduits which is external to the other and an orifice, drilled in the shield, capable of receiving said external conduit, means of solida-rization being put in works to secure this external conduit 15 to the edge of the orifice or to the shielding zone surrounding the orifice.

Thus, thanks to these provisions, the cooling plate is secured to the shielding in a single zone, which eliminates any problem of mechanical stresses due to expansion during operation.

Furthermore, still due to the simple structure of the cooling devices according to the invention, cooling plates thus arranged are simpler to manufacture, and therefore less expensive, than the plates currently known.

A variant of the plate which has just been described consists in making it include an axial cavity open at its two ends, the enclosure surrounding the cavity and the supply and evacuation conduits at least partially surrounding the cavity, the transverse dimensions of the cavity being sufficient for it to be possible to introduce an elongated and cylindrical cooling device therein.

One can thus constitute a mixed cooling device, associating a cooling plate and a cooling box, which gives a particularly favorable result since, for a space requirement which is that of a cooling plate, 9 ”are carried out”. · Deep cooling within the refractory material, on the one hand, and a heat shield is provided to protect the shielding, on the other hand.

The invention will be better understood on reading the following description of some of its embodiments, given by way of non-limiting examples. In this description, reference is made to the appended drawings in which: - Figure 1 schematically shows a mode of realization-10 sation of a heat exchange device established in accordance with the invention, - Figure 2 is a sectional view according to line II-II of Figure 1, - Figure 3 shows schematically another embodiment of a heat exchange device according to the invention, - Figure 4 shows schematically yet another embodiment of a heat exchange device according to the invention, FIG. 5 schematically represents yet another embodiment of a heat exchange device according to the invention, FIG. 6 is a side view in section a cooling plate arranged in accordance with the invention,

25 - Figure 7 is a sectional view along line VII-VII

of the cooling plate of FIG. 6, - FIG. 8 also represents a variant of the cooling plate of FIGS. 6 and 7, - and FIGS. 9 and 10 respectively represent two possible arrangements of cooling plates and boxes to the invention.

Referring first to Figures 1 and 2 relating to a first embodiment of the invention, the cooling box 60 comprises an enclosure 61 cy-35 lindrique of revolution having a flattened shape, that is to say say that its height is small compared to its diameter.

A conduit 62 for supplying the cooling liquid 10 opens tangentially into the enclosure 61.

For the evacuation of the liquid, there is provided, on the one hand, an outlet orifice 63a, substantially diametrically opposite to the orifice of the supply duct 62 and, on the other hand, a channel 63 extending radially approximately from the center to the periphery of the enclosure 61; the channel 63 is located equidistant from the flat walls 64 of the enclosure and it is flattened and profiled, as visible at 65 in FIG. 2, so as to disturb the flow of the liquid only to a lesser extent.

Two holes 66, drilled respectively in its lateral faces 67 and centered in the center of the enclosure, allow the coolant to pass from the enclosure into the channel 63 ..

To facilitate this passage, provision is also made, on each side of the channel 63 (that is to say between each face 67 of the channel and each wall 64 of the enclosure), a deflector device 68 consisting of blades wound in direction of the center of the holes 66.

The channel 63 extends in the direction of the rear of the cooling plate 60, that is to say opposite of the zone (or nose) 69 intended to be turned towards the region of the blast furnace at cool when the box is installed in the functional position.

The channel 63 opens into a discharge chamber 70, contiguous to the enclosure 61 and situated at the rear of the latter.

A duct 71 for discharging the coolant opens in the chamber 70, preferably opposite the orifice through which the channel 63 opens into the chamber 70 or opposite the orifice 63a.

The coolant (generally water), brought in through the line 62 (arrow 72), arrives in the enclosure 61 in which, taking into account its shape, it initiates a spiral movement (arrow 73). Part of the liquid from the external vein, which in fact is the most heated in contact with the wall of the nose 69, passes directly through the orifice 63a (arrow 73a) to be evacuated. The

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11 rest of the body of water, once arrived towards the central region of the enclosure, is recovered by the deflector devices 68 (arrow 74) and enters the channel 63 from where it passes into the chamber 70 (arrow 75 ) then exit 5 through conduit 71 (arrow 76).

Note that the entire cooling box; ment 60 is between two parallel planes containing the faces 74 of the enclosure. As a result, the box 60 can be easily inserted, through the shield of the blast furnace, into its housing made in the refractory material. Conversely, it can easily be extracted therefrom, for example with a view to replacing it.

FIG. 3 (in which the elements identical to those of FIGS. 1 and 2 are designated by the same reference numeral 15) represents a cooling box (called "vaporization") 77 whose arrangement corresponds generally to that of the box 60 of Figures 1 and 2, with the exception of the channel 63 which is located outside the enclosure.

20 More precisely, one associates with one of the walls of the enclosure (in this case that, 78, which is arranged at the top in the position for mounting the box on the shield of the blast furnace, as shown in FIG. FIG. 3) an elongated shell 79 delimiting with the wall 78 an external channel 80.

A supply duct 62 opens tangentially into the enclosure 61, for example according to the configuration of FIG. 1 or according to any other equivalent configuration, while a discharge duct 71 starts from the channel 80. Similarly as in in the previous embodiment, vanes 68 are provided to cause the liquid to pass through a hole 66 making the enclosure 61 communicate with the channel 80.

Another hole 81 is provided to connect the discharge chamber 70 to the channel 80.

During operation, the vapor bubbles which form in particular in contact with the wall of the nose 69, the most thermally exposed, are torn off as and when they are created and entrained by the liquid mass in rotation in the pregnant 61.

Taking into account the gravitational field which prevails within the liquid mass, the vapor bubbles are brought back 5 towards the center of the enclosure 61 from where they pass in the channel 80. As the liquid is in continuous circulation within the 'enclosure, we are sure that it will not be able to form, along the internal face of the walls, in particular in the nose, a veil of vapor preventing thermal exchanges and that it will not be able to form non no more steam cap blocking water circulation.

The cooling box 83 shown in Figure 4 is designed, unlike the previous ones, with a central inlet and a tangential discharge.

A supply duct 84 opens out at the center of a cylindrical enclosure 85 of revolution, the liquid penetrating perpendicularly to the circular face 86 of the enclosure.

Deflector means 87, constituted for example. like those 68 in FIGS. 1 to 4, print a tangential component to the liquid in such a way that it is rotated and describes a spiral path from the inside towards the outside of the enclosure (arrow 88).

An evacuation duct 89 extends tangentially and collects the heated liquid.

FIG. 5 shows yet another embodiment of a cooling box according to the invention.

The box 90 of FIG. 5 is designed from the plate 60 of FIGS. 1 and 2 from which it contains all the 30 elements (the same reference numbers have been kept in FIG. 5).

However, a second enclosure 91 has been added which is simply constituted by a tubular conduit bent in a semicircle to conform to the rounded shape of the nose 69 of the plate 60 of FIG. 1. The tubular conduit 91 is connected to the external hydraulic network by supply and drain lines 92.

It will be noted that, in the enclosure 61 and in the conduit 9 * 13 91, the directions of circulation of the liquid are opposite (arrows 94 and 95 respectively).

As a result, in the vicinity of the evacuation conduit 93, where the liquid already heated by its passage through the conduit 91 is less effective, beneficial cooling is provided by the cold liquid arriving through the conduit 62 and opening into the enclosure 61. And conversely in the region of the conduits 71 and 92. It is thus possible to obtain a better distribution of the re-cooling of the refractory, and, in general, a better yield.

It will be noted that in FIG. 5, the cooling box 91 has been shown in a functional position, that is to say that, as already explained above, the plate extends slightly. near perpendicular to the shield 96 of the blast furnace to which it is appropriately fixed by means of an intermediate pad 97 and it penetrates into the refractory 98, its nose 99 being turned towards the hot regions of the blast furnace.

FIGS. 6 and 7 show a cooling plate 100, intended (as already indicated above) to be inserted between the shield 101 of a blast furnace and the refractory wall (not shown).

The cooling plate 100 has a cylindrical enclosure 102 of revolution, a conduit 103 for supplying the coolant and a conduit 104 for discharging this liquid.

The two conduits 103 and 104 extend, at least in an area adjacent to the cooling plate, 30 substantially perpendicular to that 105 of the walls of the enclosure which faces the shield 101. In addition, the two conduits 103 and 104 are coaxial, the conduit 104 being internal to the conduit 103 which surrounds it.

By way of example, the arrangement of the cooling plate can be as follows.

The supply conduit 103 communicates with a channel 106, pressed against the external face of the aforesaid wall 105 of the enclosure, which opens into the enclosure 102 at the * * 14 periphery thereof by an orifice 107. A the reflecting wall 108 is provided in front of the orifice 107 in order to deflect the flow of liquid so that it gushes tangentially into the enclosure.

5 Diametrically opposite to the orifice 107 is an outlet orifice 109 through which the enclosure 102 communicates with a channel 110 (for example also outside the wall 105) ending in a central chamber 111 of the enclosure. This central chamber communicates with the res-10 te of the enclosure by openings 112. In the chamber 111 are also disposed deflecting vanes 112 situated opposite the orifice through which the discharge duct 104 opens in said room 111.

For fixing the cooling plate 100 in the blast furnace, the shield 101 is pierced with a hole 113 having a diameter corresponding substantially to the outside diameter of the supply duct 103; said conduit 103, introduced into hole 113, is welded to the shield.

The cooling plate 100 is thus secured to the shield only by its central region, represented by the conduit 103 serving as a fixing sleeve.

Whatever the deformations that the cooling plate may undergo under the action of heat, it will be able to expand freely, without it being the site of destructive stresses as was the case in previous cooling plates having a plurality of attachment zones.

Of course, it will be understood that the arrangements which have just been described and which combine the means 30 for supplying and discharging the coolant with the fixing means are not dependent on the particular configuration of the enclosure shown in the figures. 6 and 7, and which has been given only by way of example, and which they can just as easily be associated with other speaker configurations, such as those previously described.

FIG. 9 represents an arrangement combining cooling plates 100, such as those which have just been described, arranged in staggered rows and cooling boxes 100a arranged in the free sectors between the plates.

It is thus possible to combine the deep cooling of the refractory, provided by the boxes, with the surface cooling, intended to protect the shielding, created by the plates.

FIG. 8 represents a cooling plate 114 which is a variant of the cooling plate 100 100 of FIGS. 6 and 7.

The plate 114 has an axial annular chamber 115 surrounding an axial cylindrical cavity 116 open at its two ends.

The annular chamber 115 is subdivided into two half-semi-cylindrical chambers 117 and 118 into which the inlet ducts 119 and outlet 120 for the coolant respectively emerge.

For the rest, the cooling plate can be arranged substantially identical to the plate 100 of Figures 6 and 7 or be shaped according to one or other of the preceding examples.

The plate 114 as a whole is shaped so that the axial cavity 116 has a sufficient transverse dimension for a cooling box 121 (preferably, but not exclusively, a cooling box arranged in accordance with the arrangements described in the main patent).

It is thus possible to constitute plate + box cooling assemblies which provide, in a same 30-blast furnace zone, cooling of the refractory wall (deep cooling) and cooling between the shielding and the refractory wall (cooling in surface or heat shield effect).

FIG. 10 represents the combination of such cooling assemblies (plate 114 + box 121) arranged in staggered rows with cooling boxes 122 alone (which, too, may preferably, but not exclusively, be of the type described in main patent) 16 "• é arranged in the sectors left free (arrangement at the corners of a hexagon circumscribed to the plates 114).

It is thus possible to create real thermal barriers, whose action extends both in depth 5 in the refractory and on the surface and which, by the arrangement of the cooling boxes, provides a good anchoring of the refractory.

As goes without saying and as it already follows from the above, the invention is in no way limited to those of its modes of application and embodiments which have been more especially envisaged; on the contrary, it embraces all its variants.

Claims (12)

1. A heat exchange device for cooling a wall of a blast furnace, according to claim 6 of the main patent application, that is to say 5 comprising: - a closed enclosure having a generally flattened shape (its length being small with respect to its diameter) and substantially of revolution around an axis of revolution, 10. a cooling liquid circulating in said enclosure, - injection means, for injecting with a tangential component the cooling liquid, located in a first region of the enclosure, and 15. evacuation means, for tangentially evacuating, this liquid, located in a second region of the enclosure te, said means of injection and evacuation liquid being respectively spaced radially from one another, said enclosure and said means for injecting and discharging liquid being arranged so that any point situated inside the enclosure does not meets no obstacle, l ors of a rotational movement around the axis of revolution, characterized in that, the means of tangential injection of the liquid opening tangentially into the enclosure at the periphery or in the vicinity of the periphery thereof and the tangential liquid evacuation means being located in the center of the enclosure, the tangential evacuation means comprise at least one set of deflector means located in the center of the enclosure and a conduit opening into one face of the enclosure in look of said deflector means. 2. A heat exchange device according to claim 1, characterized in that the discharge duct extends radially from the center of the enclosure towards the periphery of the enclosure. 3. A heat exchange device according to * 18 Ä * i claim 2, characterized in that the radial discharge duct is inside the enclosure / in that it extends substantially equidistant from two side walls of the enclosure and in that two sets 5 of deflector means are provided, these two sets being situated on either side of the above-mentioned duct. 4. A heat exchange device according to claim 3, characterized in that the radial evacuation duct is profiled externally to offer minimum resistance to the liquid in rotation in the enclosure. 5. Device according to any one of claims 2 to 4, characterized in that the radial evacuation duct opens into a transit chamber, external to the enclosure and comprising a water outlet orifice. 15 6 - A heat exchange device according to claim 2, characterized in that the radial duct is located in the upper part of the enclosure, and preferably outside thereof. 7. A heat exchange device according to any one of claims 1 to 6 or according to claim 6 of the main patent application, characterized in that the tangential evacuation means comprise a conduit opening tangentially into the enclosure, at the periphery thereof, the orifice of said conduit being diametrically opposite to the orifice of the tangential injection means. 8. A heat exchange device for cooling a blast furnace wall, according to claim 6 of the main patent application, that is to say comprising: - a closed enclosure having a generally flattened shape ( its length being small with respect to its diameter) and substantially of revolution around an axis of revolution, 35. a cooling liquid circulating in said enclosure, - injection means, for injecting with a tangential component the coolant, located * 19 "" ï in a first region of the enclosure, and - evacuation means, for tangentially evacuating this liquid, located in a second region of the enclosure, said injection means and liquid evacuation of being respectively spaced radially from each other, said enclosure and said liquid injection and evacuation means being arranged so that any point located inside the enclosure does not meet 10 no obstacle, during a rotational movement around the axis of revolution, characterized in that, the tangential injection means opening into the central part of the enclosure and the tangential evacuation means being located at the peri -15 enclosure sphere, the tangential injection means comprise at least one liquid supply conduit opening into at least one face of the enclosure and substantially in the center of said face and at least one set of deflector means located opposite the orifice of said conduit, for printing a component of force tangential to the liquid opening into the enclosure. 9. A heat exchange device according to any one of claims 1 to 8, characterized in that, for the supply and outlet of the liquid, it is provided with connection means located side by side and connected to 1 ' enclosure by conduits which extend between the two planes containing the two substantially parallel faces of the enclosure, whereby the heat exchange device is able to be mounted on the wall of the blast furnace 30 perpendicular thereto , like a cooling box. 10. A heat exchange device according to any one of claims 1 to 9, characterized in that it comprises a second enclosure covering at least the front part of the first enclosure and in that there is no communication for the coolant between the first and the second enclosure. 11. Cooling device according to one of claims 1 to 7, the injection and evacuation means comprising respectively a conduit for supplying the liquid and a conduit for discharging the liquid, characterized in that the two conduits extend approximately 5x perpendicularly to one of the walls of the enclosure, at least in the vicinity of said wall, from - substantially the central zone of said wall, in that the two conduits are concentric at least in the vicinity of said wall, and in that means for fixing the device to the shielding of the blast furnace are provided which comprise, on the one hand, that of the above conduits which is external to the other and, on the other hand, an orifice pierced in the shielding and capable of receiving said outer conduit, means of securing being used to secure the outer conduit to the edge of the orifice or to a zone of the shielding surrounding the orifice. 12. Cooling device according to any one of claims 1 to 7 and 11, characterized in that it comprises an axial cavity open at its two ends, the enclosure surrounding the cavity and the supply conduits and at least partially surrounding the cavity, the transverse dimensions of the cavity being sufficient for it to be possible to introduce an elongated and cylindrical cooling device therein.