LU82176A1 - INSTALLATION FOR PRODUCING HOT WIND AND METHOD OF IMPLEMENTING - Google Patents

Description

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I patent application Bl-2802 / EM / BM

j de, .15 ..... févxi.er ... l9..8.0 | -: -: - i Designation of the inventor I -—- | (1) The undersigned ............................ J ^ YERS..Ernestconsju ^. „Prpj? R..inâ .. x ...................

.................................................. .................. 46 .., rue..du ... c.imetièr.e..r .... Lw ^ giofc.Q.ui :. g ............................................

acting as dgjdé & ÂSâôi: - agent of the depositor - (2) .................................... ....................... BAULAJ1IRTH .... S..A .................. .................................................. ..............................

.................................................. .................. 3.2 ....... r.ue ... d.1 Alsace., ........ Luxembourg ... ....... — ...................................

i (*) of the invention concerning: ...............,. 'in.sta.ll, .ation ... of .... proâ.uc.t ± QrL..from ... Fri.t .... hot .-. And ... pr.oc.êdê..jnxs .... en ...

..............artwork".................................. .................................................. .................................................. ..........

designated as inventor (s): 1. Surname and first names .................... LEG.ILLE ... Edo.uarcL ......... .................................................. .....................................

Address ......................................... 1.6.6 ..... ..; cue .... d £ .... Tràve.S .., .... Luxembourg ........................ .......................

2. Name and first names .................... SOL ¥ .I ... Tue.c ............... .................................................. .................................................

Address .......................................... 30 .rUe ... Cbarl .eSr.Q.uin.t., .... Luxemhôurg ................................... ..

3. Name and first names .................... S.Ç.HM.Î.T ... LQ.uis .......... .................................................. ..............................................

Address ......................................... 3.9 rue ... ThëQ.dQ .re ... Eb.erbar.dt, .... Luxemb.Qiir.g ....................

He asserts the sincerity of the above-mentioned indications and declares to assume full responsibility for them.

• ...........................-..................... ........-the 19 ............

SERVICE LÔXEKEûuftGtGlS BE THE PROPERTY pppi i »fs /, â <L_ \ §JL ± ----- h- ^ H-ain.

The pre-weighed, ^ / __......

* (signature) A 680 26 _________- _ (1) Last name, first names, firm, address.

ViC ---—- BL-2802 / EM / BM

/ Patent application

J

! J

/ de ...... l.5 .-. f.§.vri © r - l-9-8 0 ^ Designation of the inventor (1) The undersigned .......... ...................... MEYERS -Er-neet -, ..... I-Hg-w-Gons -.- en — pr-Gpr- .-i-nd »-r .................

.................................................. ..................... 4.6 ....... r ue ... du ... Cemetery. / .... Luxe ^. ....................................

acting as dsx & spaxaôfc - agent of the depositor - (2) ..................................... ......................... PAUL ... WnRT, H ... S-Ju, ----------- ------...— __________________________________________ ....................................... ................................. 3.2 ........ r.ue ...- d . \ Msa.ce., ..- Luxembourg ....................................... ............

(s) of the invention relating to: .............. "InstallatiQ.a„ .d ^ .... p.mdactl.o.ïx ... dia .... yie.rLt „.. hot ^ and ... pxQ.c.é.dé ... atiÆ ... en ...

! .............artwork"................................... ..........'....................................... .................................................. ....................

| designated as inventor (s): 4. X Last name and first names ........................ SP.ED.EN.ER ... Carlo .. .................................................. ..............................................

Address ............................................ 31 Belt of · ΕθΒΐβΓ5 ·,.-_ · .Ηον8αχί .......................................

2. Surname and first names ............................................. .................................................. .................................................. .......................

Address ................................................. .................................................. .................................................. ..., ....................................

3. Surname and first names ............................................. .................................................. .................................................. ......................

Address ................................................. .................................................. .................................................. .........................................

He affirms the sincerity of the above-mentioned indications and declares to assume full responsibility.

.....: Luxembourg ......................, on ............ 2.4 ... March .. ..................... 19 ... & Q ...

......

(signature) A 68026 _; _ ~ _ (1) Last name, first names, firm, address.

/ 2 \ Mnm nranAme Λ + arlrapAa

BL-2802 / EM / W

8β. "GRAND-DUCHY OF LUXEMBOURG k of the Minister" {5¾¾¾ of the National Economy and the Middle Classes

Title issued: ....................................... 3 ”m 2¾ ^ ¾¾ Service of Industrial Property

LUXEMBOURG

Patent Application I. Application.

BOdiêté known as PAUL WURTH SA Λ 32 rue d'Alsace, Luxembourg _____________________ (1) * rt ................... — ........... .........................-........................ ..................... · * ··· ........................ ........... — .......................... "........... ......................................

represented by E.Meyere & E, Freylinger3 Ing.cons ^ en propr, ind * 3 46 me ___ (2)),. from the Cemetery. LuxembourgΛ acting as agents _______________; __________ V * deposits this <Î ^ Pse ^ v ^ ez, n ^^ 7ieuf.aenP .. ^ ii; reV ^ iMt - i3) at ..... 1 * L .. --------------- hours, at the Ministry of National Economy and the Middle Classes, in Luxembourg: 1. this request for obtaining a patent for invention concerning: "Installation of hot wind production and yrooédê implemented” _ (4) declares, assuming responsibility for this declaration, that the inventor (s) is (are): -....... .................................................. .............— .................................... ................................................-— --------------------------------------: ------ (5) 2. the delegation of power, dated ......___________., __________ on _______ 3. description in language ------------------------- - „- of the invention in two copies; 4 .............. drawing boards, in two copies; 5. the receipt of the fees paid to the Luxury Registration Office mbourg, le .Mng ± rsept ... mΆerώm..ML · neuf .... ßmL · MQixmte..Aix ... Mmf ....____________________________________________ claims for the above patent application the priority of one (of ) request (s) from (6) ......... ΓΤ ............................... ........................................... filed in (7 ) _____________________________________...._________"______________ the ........................................ .................................................. .............—------------------------------------ --------. 1 ------------- (8) on behalf of ......... ~ ----------- ---------------------------------------------------------- ---------------------------------------------------------- -----------------------------......._______...__________________ (9) take up residence for him (she ) and, if appointed, for its agent, in Luxembourg____________ 46 rue du Cimetière. Luxembourg ______________________________......__________ ______________________ (i0) * requests the grant of a patent for the invention for the subject described and represented in the abovementioned appendices, - with postponement of this grant to __________ ZÜL ____________: ______________ months.

r J one of the authorized representatives / f y U. Statement of Deposit

The above application for a patent for invention has been filed with the Ministry of National Economy and the Middle Classes, Industrial Property Service in Luxembourg, dated: February 15, 1980 -fiO '.......' Pr the Minister at ._________________________ hours / \ of the National Economy and the Middle Classes, î V P- d.

cj 4 y! , ^ "V XQ A 6B007 .........

/ 11 Mnm -Rrmo offrocea. / 01 * · ”?! tt o Kan> van “AeBnt & vtnv“ _ & “, 4b / 41 A”

BL-2802 / EM / BM

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PATENT

Installation for production of hot wind and process implemented fi î

S

The so-called company: PAUL WURTH S.A.

32 rue d'Alsace Luxembourg s 5 k c - 1 - <

The present invention relates to an installation for producing hot wind, of the cowper type, comprising an enclosure, occupied essentially by a beehive of refractory brigades, at least one cold wind intake orifice at the base of the enclosure, at least one outlet for the hot wind i located at the top of the enclosure, so cu'un ou plus *! ! several burners arranged in the upper region to burn fuels and generate the heat necessary for * Zi warming of the ruchage, as well as a process to be implemented. 10 Most of the known production installations · »% of hot wind essentially comprises two parts. A first part, called a combustion well, comprises at its lower part, a burner into which a combustible gas is injected, in particular blast furnace gas, enriched in most cases by coke oven gas, natural gas, etc. The heat released by the combustion of this gas goes up the combustion shaft, is deflected by a dome and goes back down into the second part of the cowper, called ruchage well which stores the heat in its ruchage of 20 refractory bricks. The production of hot wind consists in circulating air through the ruchage well in the opposite direction to the circulation of the combustion gases, that is to say from the bottom to the top. When passing through the ruchage, the air thus recovers the heat which was stored in this ruchage during the combustion of the gases.

Among these known installations, a distinction is made between those known as "separate wells", in which the combustion well is completely separate from the ruchage well and those known as "incorporated well" in which the "combustion well and the ruching well, albeit distinct one. on the other are juxtaposed in a common enclosure.

* In these known installations, the most stressed part, and therefore the most subject to deterioration, is the dome. Indeed, this is directly.

35 exposed to the heat and flames of combustion since it must deflect the combustion gases to the ruchage well. Therefore, the hottest place of one. such a cowper is always the dome, which is also the most stressed and therefore the most vulnerable place. The sequence of this high temperature in the dome is,! in addition to the decrease in its mechanical resistance, the increase in the concentration of Ν0χ ions which form at high temperatures and which are the cause of a preferential appearance in the dome of what is called "intercrystalline cracking corrosion ", the scourge of modern cowpers operating at high temperatures and pressures.

Cowpers with incorporated wells have the further disadvantage that the refractory partition wall between the combustion well and the ruching well is also exposed to the risk of rapid deterioration. Indeed, these are due to short circuits occurring between I the combustion shaft and the beehive and are manifested by>

Destruction of the refractory material due to the thermal shocks produced by the considerable temperature differences existing on either side of the partition wall.

This latter problem inherent in the in-I body well cowper could be solved by another type of so-called "cowper without combustion well" installation in which combustion occurs above the refractory ruching, namely in the space under the dome, or in a separate combustion chamber above the dome. An example of such an installation is described in German patent application 2 123 552. The elimination of the combustion shaft also has the advantage of an increase in the space available for ruchage or a reduction in diameter. necessary. Another advantage of this type of cons-

Itruction is a symmetrical construction.

. 30 However, cowpers without combustion wells have not solved the problem posed by the * heating of the dome and it is always the wall thereof which undergoes the most intense reheating, since either combustion occurs directly below it, or the combustion gases are sent directly to the wall of the dome.

i Consequently, the problem of intercrystalline corrosion i i does not always appear in this type of cowper.

The object of the present invention is to provide a 4L · t - 3 - a new type of cowper without combustion shaft which does not have the drawbacks inherent in the cowper according to the state of the art.

To this end, the invention provides an installation which is characterized in that each burner is integrated in a refractory wall provided with cavities corresponding to each burner and forming with the front part thereof a combustion bowl from which is emitted a conical heat flow, each of the burners being oriented so that these conical flows directly strike the entire upper surface of the beehive without it being touched by the flames.

In this type of burner, combustion takes place in a front bowl of the burner and the combustion gases as well as the heat released are directly sent to the upper surface of the refractory burner. The advantage is that the heat is transmitted where it is needed and without prior reflection on the dome. Consequently, the latter no longer acts as a deflector of combustion gases and heat and now only has a role of arch or cover des-20 tiné to close the upper part. Thanks to this design, the temperature of this vault can be reduced from 100 to 150 ° for comparable operating conditions.

Whereas in conventional cowpers the hottest, most stressed and least resistant point was the dome, in the cowper according to the present invention, the hottest point is that which is the least stressed and, moreover, that whose heat is recoverable, that is to say the upper part of the refractory beehive.

Another advantage resulting from the presence of flameless burners and the elimination of the combustion well is the reduction in the presence of ΝΟχ ions for the same temperature of hot wind.

In the simplest version, a single burner is placed in the center of the cowper's vault and the outlet port for the hot wind is located next to this burner.

In another version, the hot wind outlet orifice is located in the center of the roof and the burners i are distributed around this orifice. In this case, the burners can be three in number and have a distribution - 4 -! i "triangular or four in number and have a square distribution.

i; In another embodiment with several burners, the burners and the outlet port for the hot wind: 5 are arranged around the center of the vault, since this vault will henceforth be less stressed, in particular as a result a lower temperature and a reduction in intercrystalline corrosion, it is possible to make several openings therein for j Ä 10 the arrangement of the outlet port of the hot wind as well as for the burners without affecting seriously the static resistance of the whole. The vault can be a simple masonry vault or else be a suspended vault, that is to say made up of refractory bricks suspended by hooks 15 for anchoring to the external metal shielding.

In another embodiment, the burner (s) are simply fixed vertically on a circular slab mounted transversely above the ruching and forming, with an upper envelope, a sealed chamber into which the burner supply lines penetrate. In this embodiment, the outlet port for the hot wind can be between the slab and the beehive or emerge vertically through the center.

The invention also provides a method for producing hot wind in an installation of the latter type, this method comprising a combustion period and a wind period, characterized in that during the two periods the slab is cooled as well as the room above it. This cooling can advantageously be carried out by introducing into this chamber combustion wind during the combustion phase and cold wind during; the wind period. The cold wind flowing in this way in this chamber can be recycled and reintroduced at the base of the beehive so as to take advantage of its heating 35 in the chamber above the slab. Besides the effect of re- | cooling, the circulation of the cold wind in this chamber ensures a pressure equalization on both sides j, I I of the slab.

According to another embodiment, a cooling system is provided in the slab and in which water or reusable air is circulated in the process implemented.

Other particularities and characteristics ressor-5 derive from the detailed description of some embodiments presented below, by way of nonlimiting examples, with reference to the appended drawings, in which: FIG. 1 shows a schematic view, in vertical section, of a first embodiment of a cowper according to the present invention, FIG. 1a schematically represents a half plan view of the embodiment according to FIG. 1, FIGS. 2 and 2a are views analogous to the previous figures and show a second embodiment, Figures 3 and 3a are views corresponding to those of Figures 1 and 1a and illustrate a third embodiment, Figures 4 and 4a correspond respectively to Figures 1 and the embodiment with a single burner, but with a suspended vault.

Figure 5 shows schematically a view, in vertical section, of the upper part of another embodiment of a cowper according to the invention, Figure 5a is a partial plan view of the embodiment of Figure 5 , Figure 6 shows a variant of the embodiment of Figure 5, with a diagram illustrating the process used.

FIG. 7 diagrammatically illustrates the method described in relation to FIG. 6, but this time, applied * to the embodiment of FIG. 5, FIG. 8 diagrammatically illustrates an embodiment similar to that of FIG. 6, but with a slab. 35 cooled in air, FIG. 8a illustrates a horizontal schematic section along the plane a-a through the slab of FIG. 8, FIG. 9 illustrates a variant of the method described w with reference to FIG. 6.

- 6 - ί i ·; n | FIG. 10 schematically illustrates a variant i of the embodiment of FIG. 8, with a slab cooled with water, FIG. 10a shows a horizontal schematic section 5 along the plane aa through the slab of FIG. 10, Figures 11 and 11a show an embodiment similar to that of Figure 2, Figures 12 and 12a show the adaptation of the suspension-> board of Figure 11 to the embodiments with a slab, ί = 10 In the different figures we will use the same {reference numbers to designate the same elements.

FIGS. 1 and 1a illustrate the upper part of a first embodiment of a cowper 10. This cowper comprises a single well 12 consisting of a ruching of refractory bri-15 ques which are alternately heated and traversed by wind from bottom to top to recover the heat stored in the refractory brickwork. Well 12 is | closed at its upper part by a vault 14 made up of a brickwork of refractory bricks 16 surrounded by a 120 exterior metal shielding 18. In this vault 14 is provided an outlet 20 for discharging the hot wind rising through the refractory ruching from well 12.

According to the present invention, there is provided in the embodiment according to Figure 1 a burner 22 I 25 which may be of the kind described in the French patent

Il 205 382. It is a burner consisting essentially of an enclosure 24 provided with an inlet 26 for combustible gases and an inlet 28 for combustion air, the actual combustion taking place in a bowl 30 30 in which also a pilot flame not shown.

,; The characteristic of this burner is to produce a very high thermal radiation by virtue of a whirling flame inside the bowl 30. The burner will simply be fixed on a flange 32 of the shield 18 of the vault. 14, tandii than an opening 34, preferably slightly divergent with! an opening angle adapted to the angle of the emission cone of the burner I, will be designed in the refractory masonry 16. This “jhj. emission cone is represented schematically in dotted lines - 7 - * by the reference 36.

During the heating phase c_: refractory briquetting, the combustion gases and air are introduced into the burner 22 at a pressure slightly above atmospheric pressure to ensure very rapid mixing and a continuous flow of combustion gases jnsqu at the bottom of the ruching well 12. The emission of the combustion gases and the thermal radiation take place at a divergent angle represented by the cone 36 and the minimal heating occurs at the upper surface of the refractory ruching, that is to say that is, really where heat is needed and where it can be recovered.

On the other hand, the vault 14, unlike the vaults and domes of all the installations known up to now, 15 is less exposed to thermal radiation and remains "in the shade" of the heat given off by the burner 22.

To reach a set temperature of the hot wind of 1250 ° C, which is the case for modern blast furnaces, the temperature of the refractory beehive, at least in the upper part, must be raised to 1400 ° C. To reach this temperature, 1 = temperature at the burner outlet must reach 1500 ° C. However, if one works in conventional installations with such temperatures, the temperature of the dome which reflects the combustion gases 25 and the heat from the combustion well to the ruching is greater than 1400 ° C. to which the temperature of the bricks must be brought refractory, that is to say that the dome temperature can rise to 1450 ° C and even beyond. Of course, at such a temperature, its resistance is considerably reduced and, moreover, it is exposed to the phenomenon of microcrystalline corrosion.

On the other hand, for comparable operating conditions, that is to say a heating of the upper part of the beehive at 1400 ° C and a combustion temperature of 1500 ° C, the temperature undergone by the vault 14 n ' is that approximately 1300 ° C, which is a difference of about 150 C compared to the temperature of the cou-j poles of conventional installations. However, it is good _J. known that a decrease in temperature âe 100 °, or / ^! · *; Î - 8 - i even at 150 ° C, is considerable for these thermal conditions, in particular as regards the increase in: | the static resistance of the vault and the reduction in the risks of intercrystalline corrosion.

jij 5 In addition, given the short distance between the burner iij and the refractory burnishing, and taking into account a better ex- ijj ploitatlcn of the burner used in comparison with the burners used in conventional cowpers, it is even there _ Î possible not to have to operate at 1500 C at outlet 10 of the burner to heat the bricks to 1400 ° C, or else, 1 operating at 1500 ° C, to have the possibility of carrying? the temperature of the upper part of the beehive above 1400 ° C.

j I The proximity of the burner 22 to the refractory beehive 15 also allows better regulation of the temperature of the beehive and, consequently, better control over the j: temperature of the hot wind at the outlet of the cowper.

• Another important advantage is the reduction of | ion formation ions. Indeed, experience has shown that this formation is very important at high temperatures. vées in particular above 1400 ° C., which means, as has already been mentioned, that we find, in conventional cowpers i, the highest concentration of NO ions in the i x; cupola. Now, if it is possible to reduce the temperature of the coupling to a value lower than 1400 ° C., one of the j causes or the conditions favorable to the formation of ions N0 ~ j is eliminated. say that the concentration j of en ions is significantly reduced and, at the same time, the risks of occurrence of j intercrystalline corrosion.

î 30 It goes without saying that the suppression of the heating of the parts which should not be it, such as for example, the walls of the combustion shaft and especially the dome, allows a reduction of the fuel necessary for the heating of the refractory casing, or much better heating of it with the same amount of fuel. In either case, there is, of course, an energy gain.

jj Whereas in the case of the cupolas of the classic cowpers, due to the thermal stresses of the dome, it was necessary to respect strict conditions as regards its geometry and to avoid, as far as possible openings in it, in order to increase its static resistance, we will now be more free for the geometry of the vault described above, that is to say that we can give it the shape that is appropriate and that we can make the necessary openings there. This is the reason why it is possible to provide numerous variants, some of which will be described below, with reference to the following figures.

Figures 2 and 2a illustrate an embodiment in which the outlet 40 of hot wind is provided in the center of the vault above the ruchage well 12. Instead of providing a single burner as in Figure 1, it is expected that 15 burners 42a, 42b, 42c and 42c, each of identical design to the burner 22, but of reduced size. These burners are arranged in a square at regular intervals around the outlet 40 of the hot wind. These burners 42a, 42b, 42c and 42d will preferably be slightly inclined with respect to the longitudinal axis of the well, so that the thermal radiation cone of each burner touches the entire upper surface of the ruchage well. The shape and the inclination of the openings in the masonry of the vault 44 will of course be adapted to the inclination of the burners.

In the embodiment shown in FIGS. 3 and 3a, four burners 52a, 52b, 52c and 52d (not visible) are provided on the roof 54. These burners 52a, 52b, 52c and 52d are identical to those of Figures 2, however their arrangement is different. As can be seen, the outlet 30 for hot wind is no longer located in the center of the vault but next to it, while the four burners 52a, 52b, 52c and 52d are arranged in a square around the center of the arch 54.

FIGS. 4 and 4a illustrate an embodiment 35 similar to that of FIGS. 1 and 1a, with the same burner 22 disposed in the center of an arch 63 and with a hot wind outlet 20 juxtaposed with the burner 22. The difference compared with J to the embodiment according to Figure 1 is that the vault 63 is no longer masonry, but that the refractory lining --- --- / * - 10- 67 is hooked. by means of anchor bricks 65 to the external shielding 69 of the vault 63. This makes it possible to further flatten the vault 63, that is to say to bring the burner 22 even closer to the upper surface of the pitching well 12 and thus intensify the benefits that result from this rapprochement, as described above.

It is understood that the embodiments of FIGS. 1 to 3 can also be designed with an arched roof as shown in FIG. 4. However, these 10 variants will no longer be described in detail.

Figures 5 and 5a illustrate an embodiment with four burners 64a, 64b, 64c and 64d, which are mounted inside the head 60 of a cowper immediately above the ruching well 62. These burners are mounted vertically 115 on a support slab 66 arranged transversely above the upper surface of the well 62. The | burners are arranged symmetrically in a square around one; ! central outlet 68 which rises vertically through the I slab 66.

; The burners 64a, 64b, 64c and 64d are, of course, of the type described above and the associated openings in the slab 66 are adapted to the cone of thermal radiation of the burners, so that the entire upper surface of the ruching well 62 is subject to heating and combustion gas.

The supply of the four burners 64a, 64b, 64c and 64d is carried out by means of two circular main lines 70 and 72 arranged around the head 60 and bringing I, respectively, the combustion air and the combustible gases.

; 30 Each of the four burners is connected to the two circular pipes [I - circulars 70 and 72 by means of radial pipes 74 and 76 | '' each provided with a closing valve 78 and 80.

j | The head 60 of the cowper is closed by a sealed envelope 82 provided with accesses 84 necessary for inspection and ί1 35 for replacing the burners and defining a chamber 86 above the slab 66. This envelope 82 ensures by con- jj sequent · sealing to the outside. This chamber 86 will preferably be cooled by means of an appropriate circulation J of a cooling fluid, as will be described more in - II -

Figure 6 first shows a variant of the embodiment of Figures 5 and 5a. In this embodiment, there are again four burners 94a, 94b (not visible), 94c and 94d, mounted symmetrically in a crown on a slab 96 above the 5 ruching well 92 and inside the head 90 cowper.

The essential difference between this embodiment and that of FIGS. 5 and 5a is that the outlet of hot wind 98 is provided in the side wall between the slab 96 and the upper surface of the refractory beehive 92.

The supply of fuel gas to the burners is also carried out by means of a circular pipe 102 provided around the head 90 and connected by radial pipes 104 and a shut-off valve 106 to each of the burners 94a, 94b, 94c and 94d. However, unlike the previous embodiment, the supply of combustion air is carried out by means of a pipe 100 penetrating vertically and axially inside the head 90 and connected through ends of pipe 108 to each of the burners. The head 90 is also closed by means of a sealed envelope 110 provided with openings 112 to provide access to the burners, and defining a chamber 116 which can be cooled.

The casing 110, as well as the casing 82 (FIG. 5) are provided with one or more openings 114 to ensure the regulation of the pressure and the circulation inside the head, in the chamber formed by the casing 110 and the slab 96 for supporting the burners.

FIG. 6 also schematically shows, in bold lines, an advantageous embodiment for effecting the cooling and the pressure equalization, in particular the presurisation, of the chamber 116.

For the ventilation of the chamber 116, the openings 114 are connected through a pipe 118 and a valve 120 to the atmosphere. The ruching well 92 is also connected to the atmosphere through a line 122 and a valve 124 35 opening into a line 128 provided at the base of the ruching well 92 and through which the combustion gases normally exit when the heating of the well.

XLhe supply line 100 of the combustion air burners communicates with the interior of the chamber 116 through several, preferably four, openings 130, these openings 130 preferably being provided with adjustment valves. indicated schematically in 132.

The cold wind intake orifice at the base of the • i I 5 castor well 92 is represented diagrammatically by the reference 134 and is supplied by a main pipe f | 136 through a valve 142. This main line 136! J cold wind also communicates through a valve 149, an i, line 138 and a control valve 140 with line 100 to: _ "10 through which is introduced the combustion air to the burner.

I At the start of each combustion or heating phase? fage of the well 92, it is necessary to ventilate, both the HP chamber and the interior of the well, since these enclosures were, during the prior phase, under pressure. At j 15 - this effect, it suffices to open the valves 120 and 124 to let the air, with expansion at atmospheric pressure i, escape from the chamber 116 and from the well 92, respectively through the conduits 118 and 122.

I During the combustion period, the interior of the chamber 116 is cooled by extracting through the openings 114 a portion of the combustion air entering through the line 100 through the openings 130 and the regulating valves 13 At the end of the combustion period and before the wind period, that is to say the admission of cold wind by S 25 the orifice 134 at the base of the ruching well 92, it is necessary to! surise the chamber 116 to adapt the pressure in the chamber! bre 116 to that of the wind in the beehive, pressure can fj rise up to 6 bars. This pressure equalization is done, advantageously, by placing the main line 30 136 not only in communication with the interior of the ru chage 92 through the valve 142 for the introduction of cold wind into the ruchage 92, but also in communication with the interior of the chamber 116 through the valve 140, the line 138, the line 100, the openings 130 and the adjustment valves 132. Therefore the pressurizations of the chamber 116 and the well 92 will be made in parallel and the pressure differences on either side of the slab 96 \ I will be practically zero during the entire filling period of the well 92.

- 13 -

To prevent the cold air for pressure equalization in the chamber 116 from entering through the burners in the well 92, provision is made between each of the burners 94a, 94b, 94c and 94d and the intake pipe 100 for the valves indicated 5 schematically by 133.

The cooling of the chamber 116 during the entire heating period of the cold wind, called the wind period, will be carried out in a similar manner to the pressurization and as a result of this operation. In other words, during the admission of cold wind through the orifice 134 and the main line 136, a certain amount of wind is deflected through the valve 149, valve 140, more or less open for this purpose, and the pipe "138 towards the interior of the chamber 116. To ensure circulation and cooling in the latter, the air, heated from this manner in the chamber 116, is evacuated through the openings 114 and the pipe 118 towards the atmosphere During cooling, the valves 132 are adjusted so that the circulation in the chamber 116 maintains a substantially constant pressure equal to that obtained during the prior pressurization.

Instead of evacuating the air through the holes 114 and the valve 120 to the atmosphere, it is possible to connect the line 118 to the line 122, as shown diagrammatically in dotted lines 144, and return this air through the line 122 and the smoke evacuation orifice 128 inside the ruching well 92 where this air will be mixed with the cold wind admitted by the orifice 134. In this way, one can take advantage of the heating of the air used to cool the chamber 116 by recovering the heat removed by the cooling.

However, in this case, a pressure booster must be provided in line 138 to compensate for the pressure drop suffered in the cooling circuit.

In order to overcome a possible breakdown in the cooling and pressurization circuit of the chamber 116, 35 due, for example, to a malfunction of a valve and which can significantly increase the risk of an accident, it is preferable to provide in the envelope 110 an opening il46 connected to a source of cold pressurized gas such as, for example, nitrogen. Such a booster circuit will normally be out of operation, but will be automatically put into service as soon as the temperature in the chamber 116 exceeds a predetermined threshold or the pressure in this chamber 116 drops below a lower critical value.

5 It is also possible to provide through the slab 96 a small opening connecting the chamber 116 inside the ruchage well 92 so as to have additional security i against an accidental excess difference in! pressure on both sides of this slab.

10 The pressurization and cooling process of! | the chamber 116 can also be applied to the embodiment of FIG. 5 to pressurize and cool the chamber 86. It is in particular possible that the openings 130 and the adjustment valves 132, provided in the case of; | Figure 6, in line 100, or provided on lines i! M 74 with regard to FIG. 5. It is also possible to provide a slightly modified system described below | ; M below with reference to Figure 7.

In this FIG. 7, we have taken up the constructive elements explained with reference to FIGS. 5 and 5a and for

Ivues of the same references as in these figures. We have also transposed on this figure 7 the block diagram illustrated with reference to figure 6 and we have kept the same | references to designate identical elements. However, unlike the embodiment of Figure 6, the | auxiliary pipe 138 of cold wind terminates and in the circular duct for supplying combustion air 70 and I in an auxiliary circular pipe 148 connected by one or more small pipes 150 inside the chamber 30 bre 86.

~. During the combustion period, part of the combustion air I admitted through the circular pipe 70 into, j * j? I the burners is deflected through the regulating valve 140 j in the auxiliary circular pipe 148 to be introduced into the interior of chamber 86 for cooling purposes. Evacuation of air from inside the room | 86 can, again, be produced by the openings 114 and 4 the line 118.

During the wind period, the pressure equalization /: - 15 - I in the chamber 86 and the cooling inside i thereof are carried out by introducing cold wind through the line 138 into the circular line auxiliary 148 and from there inside the chamber 86. It is possible to provide additional valves, not shown, to isolate, during the combustion period, the circular pipe 70 from the pipe 138 and, when of the wind period, the pipe 138 of the circular pipe 70. For more information, reference will be made to the description 10 given with reference to FIG. 6. Note however that in the embodiment of FIG. 7, has also provided a booster circuit 146 for the introduction of an auxiliary cooling and pressurizing gas.

It is of course also possible to provide in the example of FIG. 6 the system for injecting cooling air and pressurizing through an auxiliary circular pipe as in the case of FIG. 7.

Figure 8 shows schematically the upper part of a cowper similar to that described with reference to Figure 6 comprising a similar arrangement of the burners 94a, 94b, 94c and 94d, as well as a similar system for pressurizing and cooling the chamber 116. However, by way of illustration of a variant, the openings connecting the pipe 100 inside the chamber 116 are indicated, at a higher level represented by 152 in FIG. 8. These openings 152 comprise , of course, also adjustment valves, represented schematically by 154.

Unlike the previous embodiment, no-

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30 particularly that of FIG. 6, the embodiment shown in FIGS. 8 and 8a comprises a slab 156 inside which a cooling circuit has been provided consisting of a whole series of pipes 158 embedded in the mass of the slab 156. In the figures, these pipes 158 are arranged pa-35 paralleling, but it is obvious that they can be arranged differently, in particular in a circle or in a spiral to cover the entire surface to be cooled. These pipes 158 are connected, on the one hand, to a main distributor 160 and, on the other hand, to a manifold 164 connected respectively to i - 16 - each of the pipes 158.

The cooling circuit of the slab 156 shown in Figures 8 and 8a is designed to operate in air. Therefore, it is advantageous to connect this cooling circuit of the slab 156 to the supply circuits of a group of cowpers with combustion air. In fact, it is known that the hot wind production installations for blast furnaces comprise a group of cowpers, that is to say.

at least two alternating cowpers, one being at the combustion period, while the other is at the wind period and vice versa. There is therefore generally provided a system

Common supply system for supplying combustion air to each of the lines 100 of each of the cowpers. In the case of FIG. 8, it is therefore possible to incorporate the cooling-down circuit 15 of the slab 158 in the combustion air supply system so that the combustion air passes through the pipes 158 before get into the burners.

The manifold 164 is connected through two pipes 168 and 168 ′ (see FIG. 8a) each comprising a valve 20 170 (see FIG. 8) to the two pipes 100 for supplying combustion air to two cowpers.

When the cowper shown schematically in Figure 8 is in the combustion period, the valve 170 | is open and the cooling air circulating in the II2S pipes 158 is introduced into the line 100 supplying the burners with combustion air. On the other hand, when the cowper switches to the wind period, the valve 170 is closed and the air for cooling the pipes 158 is transmitted through the line 168 'to another cowper who is at this time in the combustion period. Consequently, in addition to i "the pressurization and the cooling of the chamber 116 provided normally as in the case of FIG. 6, the embodiment * * of FIG. 8 guarantees an additional cooling • .i μ of the slab 156 as well during the period.

I 35 combustion only during the wind period.

FIG. 9 shows another variant applied to a co \ per of the kind described with reference to FIG. 6 and comprising »additional cooling of the slab 96. This additional cooling is achieved by means of a chamber of>> '* _ ji - 17 - I flat cooling 172 specially provided for this purpose 1 immediately above the slab 96 and separating the latter I from the interior of the chamber 116. This chamber 172 is connected through a line 174 and a booster 176 to 5 the auxiliary line 138 which, as in the embodiment of FIG. 6, connects the main line 136 of cold wind to the line 100 of combustion air intake, the outlet of the cooling chamber 172 is connected through an adjustment valve 180 and a pipe 178 to the ori-10 fice 128 exhaust flue gases at the base of the cowper.

To avoid a direct passage from the inlet to the outlet of the chamber 172, the latter is preferably divided into compartments to form baffles and force the air to cool down. to circulate throughout the room.

During the combustion period, part of the combustion air circulating in the line 100 passes through the upper part of the line 138 and is sent by the booster 176 to the cooling chamber 172. The evacuation of the Chamber 172 is made through the valve 180, the line 178 and the valve 124 to the atmosphere.

During the wind period, cold wind is admitted into the cooling chamber through the line 138, the booster 176 and the line 174. This wind flowing in the cooling chamber 172 is preferably re-cycle through the line 178 and the orifice 128 to take advantage of the heat removed from the chamber 172.

Besides the cooling of the chamber 172, the pressurization and the cooling of the chamber 116 are carried out in the same manner as in the case of FIG. 6.

It is of course possible to replace, in the embodiment of FIG. 9, the cooling chamber 172 by a cooling pipe as in the embodiment of FIG. 8. Conversely, it is; possible to replace the pipe cooling of the embodiment of FIG. 8 with the cooling chamber provided in FIG. 9.

Fig.lOetlOa finally show an embodiment similar to that of figure 8, with a cooling-down circuit provided inside the slab 156. As in / '“18 - the example of figure 8, a number of pipes 158 are housed in the mass of the slab. These pipes are connected on the one hand to a distributor 182 and on the other hand to a collector; tor 184. However, unlike the example in FIG. 8, 5, the coolant circuit is circulated! slab 156, just cooling water. Of course, the pipes 158 can again be arranged in parallel or have other configurations, in particular in a circle or in a spiral, in order to cover the entire surface of the slab I 10 156. The cooling and the pressurization of the chamber 116 are to again performed as in the embodiment of Figure 6.

The different cooling variants shown in FIGS. 8, 9 and 10 have been described in relation to: a cowper of the type described with reference to FIG. 6. It is however obvious that the embodiments of FIGS. 8 to 10, | as well as the methods implemented, are just as well IJI applicable on an embodiment like that of the! Figure 5, or Figure 7.

Finally, it should be noted that in the mode of realization! sation of FIG. 10, the circuit 158 can be replaced by a cooling chamber similar to the chamber 172 in which water or another cooling liquid is also circulated.

FIG. 11 shows an advantageous example of the design of the head of a cowper, applicable in particular to the modes | of embodiments of FIGS. 1 to 4, FIG. 11a being a view from above of the upper part of the cowper. In this example, there are four burners 190a, 190b, 190c and 19Od mounted in

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I - 30 square around the center of a vault 192, the outlet 194 of vent f! on the side. In this example, the shape of! the vault is better suited to the burners in that for each burner the vault forms a cavity 196 matching and extending the refractory part of the burners to form with p; 35 this the combustion bowl.

i 1

A series of crossed beams 200, 202, 204 integral with the shielding of the vault 192 support both the latter and m / the burners.

i | yj, FIGS. 12 and 12a illustrate the adaptation of the assembly according to FIGS. 10 and 10a to the embodiments of FIGS. 5 to 10. The four burners 206a, 206b, 206c and 206d are mounted on a slab 208 which, like the vault 192 of FIG. 11, includes cavities 210 matching the shape 5 of the refractory part and forming with it combustion tanks 212. The slab 208 and the four burners 206a, 206b, 206c and 206d are supported by beams 212. These beams 212 are in turn carried by the outer casing 214 which extends the outer shielding of the well 92.

JL

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Claims (27)

1.- Installation of production of hot wind, of the cowper type, comprising an enclosure, occupied essentially by a beehive of refractory bricks and provided with at least one orifice of cold air admission at the base of the enclosure and d 'at least one hot wind outlet orifice located at the upper part of the enclosure, as well as one or more burners I their mounted in the upper region to burn combustible fuels and generate the heat necessary for warming the I! 10 ruchage, characterized in that each burner is integrated! .. * ji in a refractory wall (14,44,54,63,66,96,156,192,208) p provided with cavities corresponding to each burner and forming I with the front part of that here a combustion bowl! i! from which a conical heat flux is emitted, each of the 15 burners being oriented so that these conical fluxes directly strike the entire upper surface of the beehive without it being touched by the flames. | 2. - Installation according to claim 1, characterized by a single burner (22) mounted in the center of a vault 20 (14,64) provided above the beehive (12), the outlet orifice (20) of the hot wind is also provided in this vault (14,64), next to the burner (22). 3. Instllaation according to claim 1, characterized in that the outlet orifice (40) is located in the center of a vault (44) and in that several burners (42a, 42b, 42c, 42d) are mounted in the arch (44) symmetrically around j of the outlet orifice (40) and inclined with respect to the axis i | vertical of the enclosure (12). J 4. - Installation according to claim 3, characterized by the presence of four burners (42a, 42b, 42c, 42d) dis- || placed in a square around the orifice (40). 5. Installation according to claim 3, characterized in that the outlet orifice () of the hot wind and more • * i il sieurs burners (52a, 52b, 52c and 52d) are arranged around ί ^ J 35 of the vertical axis of the enclosure (12) in a vault (54). 6. Installation according to any one of claims 2 to 5, characterized in that the vault (14,44,54) is pj a masonry vault consisting of masonry (16) of refractory brick surrounded by a exterior metal shield (1 - 21 - 7. Installation according to any one of claims 2 to 5, characterized in that the vault (14, 44, 54. is a vault made of refractory bricks (67) hung by means of anchoring bricks (65) to a outer metal shield (69). 8. Installation according to claim 1, characterized by several burners (64a, 64b, 64c, 64d, 94a, 94b, 94c, 94d) mounted symmetrically in a crown and fixed vertically on a circular slab (66, 96) mounted transversely - 10 ' dirty above the beehive (62, 92) and forming with an upper envelope (82, 110) a sealed chamber (86,116). 9. Installation according to claim 8, characterized by a central pipe (68) for exiting a hot wind emerging vertically through said casing (82) and the slab (66) and by external circular pipes (70, 72). supply of burners (64a, 64b, 64c, 64d) with combustion air and combustible gases and connected to these by radial pipes (74, 76) provided with shut-off valves (78, 80). Installation according to claim 8, characterized in that the outlet port (98) for hot wind is provided in the side wall of the beehive (92) between the slab (96) and the upper part of the beehive and in that the the burners (94a, 94b, 94c, 94d) are supplied with combustion air and combustible gases respectively by a pipe (100) penetrating vertically and centrally through the casing (110) between the burner ring and by an outer circular pipe (102) connected by radial pipes (104) and closing valves 30 (106) to each of the burners (94a, 94b, 94c, 94d). 11. Installation according to any one of claims 8 to 10, characterized in that the chamber (86,116) is cooled by means of a cooling fluid. 35 12. - Installation according to any one of the claims 8 to 10, characterized in that the ex-I inner envelope (82, 110) is provided with access openings (84, 112)! for inspection and replacement of burners. —JT ”, 13. - Installation according to any one of the resales * ï - 2 2 - j dications 8 to 12, characterized in that the outer envelope * (82, 110) is provided with openings (114) for the 'jj î | regulation of the pressure in the chamber (86, 116). , -j: j 14. - Installation according to any one of the reven-;, j jj 5 dications 8 to 13, characterized in that the pipes (70, j 100) communicate through a pipe (138), a valve (140) Iet a valve (149) with a main line (136) connected to the cold wind inlet orifice (134) at the base of the well (92] | 15. - Installation according to claim 13, charac- J 10 terized by a pipe (118) connecting the openings (114) j through a valve (120) to the atmosphere. 116. Installation according to claim 15, characterized in that said pipe (118) is connected to an orifice (128) for evacuating combustion fumes provided at the base of the well (92). : · * Il 17. - Installation according to one of claims 8 i <! || to 13, characterized in that the supply air lines jj (74, 100) of combustion air from each of the burners (64a, \ l 64b, 64c, 64d, 94a, 94b, 94c, 94d) communicate with the 120 chamber (86, 116) through openings (130) provided with adjustment valves (132). ; | j 18. - Installation according to any one of the res-; | dications 8 to 13 and 15 to 17, characterized by an auxiliary circular pipe I (148) connecting the chamber (86, 116) to j | 25 the combustion air intake pipe (70, 100), of a j | part, and through a pipe (138) and a valve (140) to j | a main pipe (136) connected to the cold wind intake orifice (134) at the base of the well (92), on the other hand. 19. Installation according to any one of the res-! 30 dications 8 to 13, characterized by a cooling circuit (158) embedded in the mass of the slab (66, 96). 20. Installation according to any one of the resales, | dications 8 to 18, characterized by a flat chamber (172) of i | cooling of the slab (66, 96) arranged immediately j | 35 above it. 21. Installation according to any one of claims 19 or 20, characterized in that the re- circuit || 1 cooling (158) or the cooling chamber (172) is connected to a cooling water pipe. U «- 2 3 - 22. Installation according to any one of claims 19 or 20, characterized in that the cooling circuit (158) or the cooling chamber (172) is connected to a cooling air line. 5 23. - Installation according to claim 22, charac terized in that the inlet (160) of the cooling circuit (158) or the cooling chamber (172) is connected through a booster (162) to a main pipe of combustion air supply and in that the outlet is connected through two lines (168, 168 ') each provided with a valve (170) to the two lines (100) of combustion air supply from two cowpers operating alternately. 24. Installation according to claim 22, charac-15 terized in that the inlet of the cooling circuit (158) or the cooling chamber (172) is supplied with cold wind by the pipe (138) connected to the main pipe (136) of cold wind and in that the outlet is connected through a pipe (178) to the base of the ruchage well 20 and through a valve (124) to the atmosphere. 25. Installation according to any one of claims 8 to 24, characterized by an opening (146) in the envelope (82, 100) of the chamber (86, 116), this opening being connected to a backup source for pressurizing and cooling the chamber (86, 116). 26. Installation according to any one of claims 8 to 24, characterized by a security hole in the slab (66, 96, 156), connecting the chamber (86, 116) inside the ruchage. 27. - A method of producing hot wind in an installation according to one of claims 8 to 26, according to which the refractory beehive is heated during a combustion period consisting in burning in each of the burners a combustible gas in a stream of air of com-35 bustion and to evacuate the combustion fumes by an opening at the base of the well, we stop the combustion period and we start a period of wind consisting in admitting! cold wind at the base of the ruchage well and to be extracted at | upper part of the well the hot wind having recovered, during * 1 * 4 ί î -24- I of the crossing of the beehive, the heat stored in it ij ci during the combustion period, characterized in that during the two periods , the slab and the chamber above it are cooled, in which the burners are arranged. 28. The method of claim 27, characterized in that, during the combustion period, said chamber is cooled by introducing part of the combustion air therein. I 10 29. - Method according to claim 27, characterized | in that, during the wind period, said i | jf chamber by circulating a part of the cold air admitted jij at the base of the ruchage well. ! 30. - Method according to claim 29, characterized I to j.i 15 in that one evacuates the cooling air from said: * chamber to the atmosphere. h! 31. - A method according to claim 29, characterized in that the evacuation of the cooling air from said chamber consists of recycling comprising the return of this cooling air to the base of the ruchage well and the introduction into this one. 32. Method according to any one of claims 27 to 31, characterized in that, before the combustion period, the said chamber and the ruching well are aerated by connecting them to the atmosphere. 33. Method according to any one of claims 27 to 31, characterized in that, at the start of the wind period, cold wind is admitted simultaneously into the ruchage well and into said chamber to increase progressively and the same time, the pressure in each of these | # enclosures, in order to ensure a pressure equalization of Ipart and other of the slab supporting the burners. 34. Process according to any one of claims 27 to 33, characterized in that independently of the cooling, the pressurization or aeration of the chamber, the slab is cooled, during the two periods, by means of a; auxiliary circuit provided inside this slab or immediately above. \ i 35. Method according to claim 34, characterized in that water is used for cooling. 36. Method according to claim 34, characterized in that the combustion air is used for this cooling by incorporating this cooling circuit in the supply line of the burners with combustion air, in that the air leaving this cooling circuit of the slab is sent to the burners of the cowper concerned while the latter is in the combustion period, while during the wind period, this air is sent to the burners of another cowper currently in the combustion period. 37. Method according to claim 34, characterized in that one uses for this cooling part of the cold wind and in that one recycles this cooling air, during the wind period, towards the base of the well of 15 ruching for the production of hot wind. 38. Method according to any one of claims 31, 36 or 37, characterized in that the cooling air is compressed in a booster. 39. Process according to any one of claims 20 to 33, characterized in that provision is made for an additional cooling and pressurization source designed to be put into service automatically as soon as the temperature in the chamber rises above a predetermined threshold or that the pressure in the chamber deviates from that in the beehive 25 by a determined value. 40. Installation according to any one of claims 1-7, characterized in that the burners and the arch are supported by beams (200,202,204) and in that the ridge is provided with cavities (196) adapted to each of the burners. 30 their. 41. Installation according to any one of claims 8-26, characterized in that the slab and the burners are suspended from beams (212) carried by the outer casing and in that the slab is provided with cavities (210) 35 adapted to each burner. j