US1827773A - Means for igniting ore - Google Patents

Description

Oct. 20, 1931. A. F. Bl-:AsLEY MEANS FOR IGNITING ORE Filed Oct. 2l. 1929 4 Sheets-Sheet 1 INVENTOR @@x'elmy ATTORNEY Oct. 20, 1931. A. F. BEASLEY MEANS FOR IGNITING ORE Filed Oct. 21. 1929 4 Sheets-Sheet 2 lNvENToR BY ma? ATTORN EY Oct. 20, 1931. A. F. BEASLEY lMEANS FOR IGNITING ORE Filed Oct. 2l, 1929 4 Shee'bs-SheeiI 5 'INVENTOR Oct. 20, 1931. A. F. Bx-:AsLEY MEANS FOR IGNITING ORE Filed OC't. 2l, 1929 4 SheeS-Sheet 4 INVENTOR @mcjeley BY MM ATTORN EY Patented Oct. 20, 1931 vUNITED STATES PATENT 'OFFICE ALFRED F.BE.ASLEY, OF KELLOGG, IDAHO, ASSIGNOR TO BUNKEB HILL & SULLIVAN DELAWARE OF KELLOGG, IDAHO, A. CORPORATION OF MEANS Fon IGNITING. .omi

Application fed October 21, 1929. Serial No. 401,335.

This invention relates to the art ofl igniting ore and consists in an improved means for causing relatively slow and gradual combustion-ignition of'increasing intensity from a relatively low initial temperature, and with a Widely spread ignition heat, so that the igniting operation will result in porous fusion of the ore particles and will prevent sealing fusion thereof.

Fusion is an inevitable and necessary factor in sintering ore in order to join or merge particles thereof, but this joinder of ore particles must be interrupted by voids, as otherwise, the sintered product will lack porosity. Porosity is necessary subsequently durin the sintering operation in order that a com ustion supporter, such as air, may be drawn through the ore bed. If the particles of ore are fused in a manner to merge them into an integral mass, subsequently without voids, then such mass will be sealed or closed to such an extent as to become substantially impervious and greatly interfere with passage ofI air therethrough. Such a non-porous mass not only prevent-s efficient sinterin but its value in subsequent treatment in the last furnace is greatly reduced.

lVhen I hereinafter speak of fusion, I mean that normal or desirable and efficient fusion wherein porosity is retained. When I hereinafter speak of sealing, I referto that defective ignition in which fusion has been so greatly advanced as to seal the ore and reduce. porosity to a minimum. The first might be termed normal or porous fusion and the second, abnormal or sealed fusion.

Heretofore, ignition has been accomplished by an ignition heat that was not only very intense but also uniform throughout the ap- -7 plication thereof. This kind of ignition,

even though spread over a relatively wide area, would inevitably result in a fusion such as would seal the ore. Further, such ignition, which has heretofore been localized over a restricted area of the ore, merely functions to kindle the latter.

In order to avoid sealing of the ore, it has y been the practice to add moisture to the latter to nodulize the ore particles and form voids. It has also been customary to add some kind of foreign substance to afford porosity, such as blast furnace slag, the latter functioning as a dilutant in lead ore that is lvery rich, al though such foreign substance performs no useful function subsequent to the sintering operation.

It will be understood that the sintering of any ore depends upon the presence therein of a combustible medium or ingredient, and in lead ore, this ingredient is in the form of sulfur, which is always in suicient quantity to afford a combustible medium. However, sulfur is not always present in uniform quantit-es even though it might be uniformly distributed. In other words, lead ore may be either rich or'lean in sulfur. Consequently, this variation of sulfur content in various runs of ore, calls for compensating features in effecting efficient ignition. Practically all of the foregoing also relates to the problem of sintering iron or copper ore.

I have discovered that scalinor of the ore can be avoided and varying conditions of ore runs compensated for by effecting ignition with a heat that is gradually applied, the temperature thereof being relatively low, at the initial area of application, and increasing as the step of ignition proceeds, and this is a primary feature of this invention.

A further feature consists in an application of ignition heat for a relatively prolonged period of time and over a relatively wide area of the ore bed.

In the most improved form of the invention, the ignition flame is elongated, preferably in the direction in which the ,ore bed is advanced, and is applied with cumulative effect in its sequential action upon the ore bed.

Because of the prolonged and elongated application of the ignition flame, heat or products of combustion, which will hereinafter be termed generically flame or flames I obtain an advanced stage of actual combustion both in depth and lengthwise of the ore bed and during what has heretofore been a mere kindling of the sulfur at the surface of the ore. Hence this invention primarily differs from previous igniters because it is acombustive-igniter, instead of a mere kindler.

It is a further feature of the invention to employ the combustion supporter as a medium for inducing the ignition ame to elongate and spread wholly responsive to the induced flow of air.

A further feature of the inventionis to elongate theA ignition flame in substantially arallel relation with the plane of the ore ed so that contact of the flame therewith will be subjacent to and along the lower length of the flame.

A further feature resides in drawing the flame diagonally into the ore bed to an increasing extent or depth so that the depth line of ignition will incline downwardly from the horizontal from the beginning toward the end of such combustive-ignition.

For the two-fold purpose of preventing loss of ignition heat and more eiectivel lconcentrating such heat on those areas of t e ore bed exposed thereto, it is a feature of this invention to rovide a hood having a flame retaining wa l in superposed relatlon to the igniting flames, and whlch is shaped to increasingly concentrate the heat of the elongated flames upon the ore bed in consonance with the action of air induction. In this connection, it is a feature of the inventionto make such wall of a material that will conserve the heat enerated by the ignition ames and therefore assist 1n rendering such ames cumulatively effective.

The invention has many other features and objects which will be more fully described in connection -with the accompanying drawings and which will be more particularly pointed out in and by the appended claims.

In the drawings:

Fig. 1 is a longitudinal vertical sectional view of that portion of a sintering machine adjacent the igniter and suction box and showing how a solid fuel may be used.

Fig. 2 -is a sectional view thereof on line 2-2 of Fig. 1.

Fig. 3 is a'sectional view on line 3 3 of Fig: 1. v

Fig. 4 is a vertical sectional view of that portion of the suction box to the-left from that end shown in Fig. 1.

Fig. 5 is a longitudinal sectional view of a modiied form ofthe invention adapted for the burning of a liquid fuel, and showing the parts in substantially the same position illus- -trated in Fig. 1.' f

' Fig. 6 is a sectional view on line 6 6 of Fig. 5.

Fig. Fig'. 5. Y

Like characters of reference designate similar parts throughout the different figures of the drawings.

The invention is shown applied to that class of sintering machine inwhich an endless series of independent and unconnected pal- 7 is a sectional view on line 7-7 of 'along an upper lap o lets are advanced or pushed by a bull wheel travel in which ore is fed to said pallets to form an ore bed of substantially uniform de th. The ore bed passes beneath an igniter w ich ignites the sulfur, and the ore bed is advanced over` a suction box that draws air through the ore to sustain and complete combustion of the combustible ingredient and thereby sinter the ore. The pallets are then moved over a dumping bight Where the pallets dump the sintered ore and the empty pallets are later returned to the upper lap of travel. Broadly, this form of apparatus is shown in the expired patent to A. S. Dwight, issued May 21, 1912, N o. 1,027,- 110, and therefore need not be illustrated in detail.

The device of this invention is addressed more particularly to a method and means for igniting the combustible ingredient in the ore, and to the coaction of the igniter with the suction box.

' Referring more particularly in detail to the drawings, a series of pallets is shown each having an open perforated bottom 1, and side walls 2, the latter bein formed on frames 3. The pallets have no en walls and hence they are adapted to endwise abut in the manner shown in Figs. 1 and 5, to form a4 substantially continuous carrier B, for the ore bed A. Hubs 4 project laterally of frames 3, a pair being lprovided on each side, and the hubs have trunnions 5 which serve as journals for rollers 6. Said rollers 6,are ada ted to be engaged by suitable notches or teet pockets 7 1n a bull wheel 8, the latter constituting motive means for slowly` advancing the pallets along the upper lap of travel of the endless pallet path. In practice, a peripheral guard, not shown, serves to hold the pallet rollers 6 in engagement with the notches in the bull wheel 8, until the pallets reach an upper position whereupon gravity comes into A The pallets advance to the left of Figs. 1

land 5, and tracks 10 may be provided for running engagement of the rollers 6, to support the pallets until the latter reach the suction box, which is vgenerally indicated at 11. The suction box is shown provided with side walls 12 which are parallel, and with end walls 13 and 14, which converge inwardly lfrom the top toward the bottom of the box.

Any suitable means, not shown, may be operatively connected with said box 11 to initiate and sustain suction sutlicient to draw air downwardly through the ore bed for the purpose of sustaining and completing combustion of the combustible ingredient in the ore during passage of the ore bed across the top of said box.

To reduce suction leakage laterally of the top edge of the suction box, hopper walls 15 are provided and the upper edges thereof are anged at 16, and supportingly engage lower y side edges 17, of pallet frames 3, as clearly shown 1n Fig. 3. The walls 15 converge inwardly and are provided with outwardly extending flanges 18, to which the side walls 12, are connected by suitable angle members 19. For a like purpose across the ends of the suctiop box, suction leakage is arrested by what are known as dead plates, one of which is general] indicated at 20 in Fig. 1, and which is in thls case the forward dead plate, the rearniost plate being indicated at 21, in Fig. 4. These dead plates afl'ord broad transversely disposed engagin faces for contact by the bottoms of the pa lets to reduce suction leakage. The up er margins of the Walls 13 and 14, are suita ly connected with said dead plates as generally indicated at 22 and 23.

At the beginning of travel of the pallets on the sintering lap of travel, they pass under feeding means which may be in the form of a hopper 24, and from which ore is fed into the pallets to a predetermined depth under control of the downwardly extending wall 25, of the ho per.

In the oregoing general description, I have set forth broadly the nature of a sintering machine, in combination with which the device of' my invention is adapted to function. Reference will now be made to that portion of the subject matter which more properly constitutes the invention, alone, and in combination with what has been set forth.

I will lfirst refer to the igniter in Figs. 1 and 2 which is designed for use ofl solid fuel. As shown, said igniter comprises a hood which includes a rear wall 26, and a bridge wall 26', extending transversely across and above the ore bed carrier B. Side walls 27 and 28, form with said Walls 26 and 26', a chamber across which is mounted a lire grate 29, on suitable supports 30. Below grate 29 is a draft chamber 31 that is shown closed across the bottom by aplate 32, and which may also form an ash pit. Above the grate 29, is the combustion chamber C, which is rendered accessible for ingress of fuel by a laterally disposed door 33; a door 34 being provided for the ash pit 31. The top of the combustion chamber is formed by a wall 35, and a forced draft is provided through a pipe 36, having nozzles 37, which delivers to the ash pit 31.

, The upper wall 35, of the igniter, extends forwardly and longitudinally of the carrier B, to the left of Fig. 1, and in the direction of movement of said carrier. l/Vhat I will term the upper section of said wall, extending froml radial dotted line 38 to a similar line 39, presents a concave inner face 40 to the flames and is in such superposed relation to the top 41, of bridge wall 26', as to form a passage of adequate size for the flame, and it will loe-clear that this section of the wall functions to guide the flames downwardly over the bridge wall. From line 39 to line 42,

the wall 35 is inwardly curved and presents will be noted that the end portions 48 and 49 are open, and it will be further noted that the lower margins of all the walls just described, terminate above the level of the ore bed A.

In order to prevent ingressing draft from entering laterally under the igniter hood structure, by reason of the spaced relation of the bottom of the latter from the top of the carrier B, and the ore bed, means is provided which will next be described.

As shown in Figs. 2 and 3, 52 designate draft arresting strips which may be provided with angle flanges 53 adapted to be secured to the bottom portions of the overhanging side walls 27 and 28, and which extend downwardly along the sides of the pallets and below the tops thereof. These draft arresting strips, as shown in Fig. 1, are shown coextenslve with the length of the igniter structure. In practice, these strips will be in sufficient lateral clearance to the side walls 2, of the pallets, to permit the latter to freely pass between said strips. If a snug fit is desired, said strips may be made of spring steel so that they willpositively engage the sides 2 of the pallets as the latter pass between said strips.

The above igniter structure is preferably formed of refractory material suitably braced and strengthened as generally shown. This igniter is suspended above and in clearance relation to the carrier B, and its ore bed A, by means which may consist of the superstructure generally designated at 50, from which the igniter is suitably hung by rods 51.

Reference will next be made to a structural feature subjacent the carrier B which vinterdependently coacts with the igniter.

The dead plate 20, has a rear portion 54 which coacts with the bottom of the carrier by abutting engagement therewith to arrest suction leakage, which portion terminates at 55. From this point forwardly, or to the left of Fig. 1, the top of the dead plate 2O is inclined downwardly, as indicated at 56, toward its forward terminal end 5 7. 'Ihe angle 58, to which the upper end of t-he wall 13 of the suction box is secured, as at 22, is also in spaced relation to the bottom of carrier B. This gradual or inclined spaced relation affords the suction box an extension zone of suction action to the right of its wall 13, viewing Fig. 1, as will be more fully described in the description of operation. j

Reference will next be made to the form shown in Figs. 5 to 7 and as the movable or ter having nozzles 65 opening to the interior of the chamber M, through the back wall 59. The fuel is force fed, andcoinbustion is supported by air conveyed by pipes 66, and controlled by valves 67, in any of the approved forms of apparatus for that purpose. It will be noted that the nozzles 65 are inclined downwardly toward the fuel bed and that they are disposed sullieiently below the top wall 60, to afford space for expansion of the flame issuing from this flame producing device. As is well known in oil burners, the flames therefrom are not to any great extent projected from the end of the nozzle and hence the inclination of the nozzles herein shown, is not for the purpose of projecting the flame down onto the ore bed, but rather to dispose the expanded flame in a position of accessibility so that it can readily be drawn or induced to play upon the ore bed, as I will later describe.

Reverting to the top or lflame retaining wall 60, the same presents a concave section 4or portion 68, from the back wall 59 to dotted line 69, and from this line 69 to its lower face, said Wall is convex down to line 70. From line 70 to the terminal end of said wall, as indicated at 71, the lower portion thereof is substantially flat and horizontally disposed. The extension zone E, and the portion of the suction box overhung by the flame retaining wall 60, eloni:

gates the flame from said burners and` pulls or draws it longitudinally along the top of the ore bed substantially in the same manner as heretofore described in connection with Figs. 1 to 3, and in the direction in which the ore bed is advanced, which is to the left of Fig. 5. Lateral draft ingress arresting strips are employed as in the preferred form.

Theoretically, the depth line of ignition would be inclined downwardly from K to O, to the right of the intersection of the suction box, and from the left of line 70, the depth line of combustion would somewhat abruptly curve downwardly as indicated at P, and then gradually descend as designated at Q, toward the bottom of the pallets, dependent upon the intensity of the flames. Some of the flames, as before stated, would be drawn along the top of the ore bed., and some would penetrate the latter, as fully indicated by the arrows.

By reason of the fact that it is not necessary to elevate the combustion chamber when liquid fuel is used, as in the case with a solid fuel, the flames may be generated ina position much closer to the ore bed. Just as soon as a portion of the ore bed has passed to the left of rear wall 59, it will be subjected to a heat that will almost Immediately dry out, at least near the surface, any of the moisture with which the ore has been previously subjected or may contain, thereby leaving the sulfur in a condition to readily ignite. In this form of the invention a bridge wall is unnecessary.

It is believed that the following description of operation will serve to make both forms of the invention entirely clear.

As the pallets approach the horizontal after leaving engagement with the bull wheel 8, they pass under the hopper 24 and are charged with ore to be sintered. The wall 25, functions to level the charge so that the ore bed A will be substantially of uniform depth. As the ore advances to the left of bridge wall 26 it is exposed to the flame from the combustion chamber C, which acts upon the ore in a manner which I will now describe in detail.

Suction from the suction box 11 exerts a powerful downward movement of air through the porous ore, and at the left of the end 44, of the flame retaining wall, the air passes vertically downwardly, as indicated by arrows D. However, as this does not satisfy suction of the box, by reason of the resistance of the ore bed A, suction also enters the extension zone E, and sets up induction to the right of the end 44, as indicated by the arrows F, trailing just in advance of bridge wall 26. This suction indicated by arrows F, not only passes diagonally through the ore bed but by reason of the fact thft it is energized by the somewhat restricted space afforded by the extension zone E, it is not so powerful from line G, to the right, as to the left, viewing Fig. 1. Line G, intersects line 42, and this is the suction box intersection with the flame passage which I have indicated at H. In other words, that area to the left of line G, is where the suction box exerts its fullest efficiency by reason of the fact that it has no restriction. However, throughout the area subjacent the flame retaining wall and to the left of the bridge wall 26, suction is exercised throughout the full width of the ore bed.

Now as a result of the foregoing, flames from the combustion chamber C, are drawn over the bridge wall 26', and downwardly through the flame passage H, and by reason of the guiding action of the flame retaining wall 35, radiation of heat is not only prevented, but said Wall 35 acts in consonance and in supplemental relation to induction from the suction box in controlling the flames. Portions of the flames are drawn downwardly and longitudinally along the top of the ore bed approximately to the end 44, of wall 35. The flames play upon and are in elongated contact with the top of the ore bed A, for a considerable period of time, and lower portions of the flame are in actual contact with the ore bed.

As the flame retaining wall conserves the heat from the igniting flames, it will be seen that the igniting heat is cumulatively- 'bed that they will almost immediately be drawn downwardly against the latter as they are not required to pass over the bridge wal as in the preferred form. Otherwise, the action of the flames in the Fig. 5, construction, is the same as 4has been described in connection with Fig. 1.

I do not means to state that this preliminary ignition-combustion is actually completed to the bottom of the pallets, but it is clear that the line of ignition-combust-ion can, and in actual practice, does reach av very considerable depth, and is in no sense superficial before the full suction action comes into play. Combusion is only completed after the ignited ore bed has completely passed over the full length of the suction box and has been subjected to a prolonged passage of air.

It now becomes pertinent to int out that the wide distribution of the ame actually prevents an excessively high heat application to any one limited portion of the fuel bed, and consequently, the danger of causing sealing fusion is correspondingly reduced, both at the surface and at depths therebelow. As a result of actual use of the device of this invention on hundreds of tons of ore, I have found it possible to eliminate the necessity of adding any foreign substance to the ore, such as blast furnace slag, in order to increase porosity of the ore, or even as a dilutant when the latter is very rich in lead, which is of course a very material saving in cost of production.

Sealing fusion is not only prevented by the prolonged igniting heat application over a wide and elongated area of the ore bed, but it is also arrested and to a maximum extent prevented by the increasing depth of ignitioncombustion from an initial to a final point of this preliminary step. It will be readily understood that* al gradual lowering of the depth of ignition-combustion e'ectively breaks up and disrupts that combustive allinity of ingredients, such as the gangues, iron and silica, and prevents sealing fusion of the ore which so quickly occurs when the ignition heat is of uniform high intensity, and is localized over a restricted area.

By reason of the elongated llame application and its relatively slowly and cumulatively increasing heat and gradual penetration to increasing depths into the ore, I find I can more effectively sinter ore irrespective of whether the sulfur content is rich or lean, and irrespective of whether'it is uniformly or sporadically distributed. It should be noted that sulfur does not ignite nearly as readily as coal, for instance, and therefore this gradual and cumulative igniting feature is just as important in its function of insuring proper and complete ignition of the sulfur content in the ore as it is in insuring that character of fusion in which porosity -is' retained.

In contrast with that type of igniter in which the flames are laterally defined and confined by the structure in which they are' housed, I have devised an igniter in which the housing structure merely serves to protect the flames from the outer air, the flames being elongated and assuming a contour of width wholly as a result of suction from the suction box. This proves the function of the draft arresting stri ps 52. In actual practice, T have removed these strips and found that the elongated flame would converge and narrow toward the center of the ore bed. By removing one of said strips, t-he flame at the corresponding side would recede and the ore bed would cease to glow and would turn dark. However, with both strips in place, the flames widen to the full width of the ore bed and cause the latter to glow.

When these strips 52 are in place, it will be seen that the igniter structure sits astride the advancing ore bed and its carrier and extends downwardly along both sides of the latter.

I now wish to make what I believe is a vital and fundemental distinction between the device of this invention and all previous patented igniters known to me in this art. Previous to this invention, ore igniters have been merely igniters whosefunction ended when a limited and superficial ignition of t-he sulfur had been effected, mainly on the surface, and for a restricted area of that surface and with no appreciable depth. Hence no actual combustion to any appreciable depth occurred prior to the time the ignited ore reached the suction box. Under such conditions, if the combustible ingredient happened to be lean or unevenly distributed, or if sealing fusion had taken place, actual combustion would not have even started in many portions of the ore bed until after the latter had reached the full zone of action of the suction box. Hence, combustion would not only be spotty, but in many instances would be incomplete after such portion of the ore bed had completely passed over the suction box. It is the function of the suction box to sustain and complete combustion after the ore has passed over the same, and if combustion has not been starten by thorough ignition, it cannot be completed by the suction box unless the latter 1s made unduly long. s

In contra-distinction to a mere ore 1gn1ter, this invention constitutes a combustionigniter in which the sulfur is notv only thoroughl ignited before it reaches the suct1on box, ut combustion has been so far. and thoroughly advanced in Ythis preliminary operative step, that when the ore reaches the full zone of action of the suction box, all that the latter is called upon to do is to sustain and complete the combustion that has already been started.

In each form of the invention, the flames are induced to low longitudinally alon the top of the ore bed and are not proJected rom the flame producing device. It is also typical of both forms that the flame retaining wall has an upper concave portion affording room for normal iiame expansion and beneath which there is a minimum ignition temperature on the ore bed because the flame is farthest away from the bed. Said wall has a convex portion extending from said concave portion which gradually deflects the flames toward and finally into engagement with the ore bed to gradually and cumulatively 1ncrease the ignition action thereon, and slowly promote fusion to avoid sealing and preserve porosity of the ore.

By reason of the advanced combustlon that is obtained in this invention during what has formerly been termed the ignition stage or step, it will now be clear that I can e'ectively sinter an ore bed of greater depth than herein shown, with a pallet travel very much increased over what has heretofore been possible.

Heretofore, igniters have been employed in which the tip ends of the llames engaged the top of the ore bed and the main body of the flames performed no igniting function; 1n others the flames were either guided or projected transversely acrossthe ore bed, in either of which events,l only a limited area of the flames actually came either into contact with,

l or exercised any other than a superficial and localized kindling action on the ore bed.

In contra-distmction to the foregoing, it will be seen that in this invention, the iiames act upon the ore bed from the time they emerge over the bridge wall, in the preferred construction, or almost immediately after they are generated, -as in the modified form. It 1s true that the llames do not instantl contact with the ore bed until after they have been deflected and drawn downwardly into engagement therewith, but they exercise a preheating function from the moment they issue forth, and throughout the balance of their travel they play upon and penetratel the ore bed substantially throughout their length, due to suction and the heat conserving wall'by means of which they are deflected. Therefore, with a given amount of combustion, I can more nearly exhaust the thermal units in effecting ignition ,and advancing combustion than is possible with any patented device known to me.

However, perhaps the greatest distinction over the rior art consists in beginning to ignite wit a relatively low temperature and' increasing the ignition temperature as ignition proceeds. t is due to ,this feature that ignition starts at zero, increasing gradually in intensity so that sealing fusion is prevented and that desirable fusion which retains the utmost of porosity, is preserved.

This has been proven by charting the igniter in actual o eration the chart showing that the line o norma or porous fusion gently and gradually rises from zero to the peak, whereas charts made on igniters having intense, localized and uniform heat, the line of fusion starts nearly at the peak of fusion, and this is the reason why sealing fusion results.

It is believed that the invention will be fully understood from the fore oing description, and while I have herein s own and described specific forms of my invention, I do not wish to be limited thereto except for such limitations as the claims may import.

Itwill nowbe clear that this invention is addressed to the problem ofi uiting and obtaining a relatively advanc stage of combustion of the ore before the ignited ore reaches the main zone or region of suction of the suction box, which, specifically in this invention, would be to the left of the end 44 of the hood in Fig. 1, or to the left of the end 71, of Fig. 5.

I claim:

1. Asa means of igniting ore for sintering purposes, va perforated carrier for advanclng an ore bed, a flame roduc-ing device, means acting through said carrier and the ore bed thereon for elongating the flames from said device lengthwise of said ore bed, means open endwise of said bed to the outer air for gradually guiding said flames into Contact with the ore bed, and means for arresting draft ingress laterally toward said flames to ermit the latter to spread responsive to sa1d iirst named means.

2. As a means of igniting ore/for sintering purposes, a perforated carrier for advancin an ore bed, an i iter structure having a ame producing evice, means acting y through said carrier for drawing flames from said device lengthwise of said advancin ore bed, said igniter structure havin a me guiding wall for advancing the ames into contact with the advancing ore bed, and said structure being open to the outer air endwise of said ore bed, and said structure extending downwardly on opposite sides of said carrier to arrest lateral draft lingress to said flames and permit the latter to spread responsive to the acti'on of said means. Y

3. As a means of igniting ore for sintering purposes, a perforated carrier for advancing an ore bed, asource of igniting flame, means actin throu h said carrier and ore bed for drawm the ame longitudinally of said ore bed, an elongated overhead means for gradually lowering and holding the llame toward and into engagement with the ore bed.

4. As a means of igniting ore for sintering purposes, a erforated carrier for advanclng an ore d, a combustion-igniter structure superposed in close relation above said advancing ore bed and having at its rear end a solid fuel flame producing device provided with a closed bottom and a bridge wall,

a to flame guiding wall extending over said bri e wall and downwardly toward said ore bed to guide flames theretoward, side walls forming with said top wall an elongated llame passage opening downwardly to and extending longitudinally of said ore ed and means below and acting throu h said carrier for drawing flames from sai device over said brid e wall and downwardly v against said ore ed through said assage.

5. As a means of igniting ore or sintering purposes, a erforated carrier for ad- 30 vancing an ore d, a combustion-igniter structure su erposed in close relation above said ore be and having end, side, and top Walls forming a combustion chamber near the rear end of said structure and open at. the bottom, liquid fuel nozzles projecting 1nto said combustion chamber, sa1d top and side walls extending forwardly longitudinall of said ore bed and said top wall exten ing gradually downwardly toward said ore be 4 and said walls forming a flame passage opening to said ore bed, and means acting below and through said carrier for drawing flames from said combustion chamber through said passage and longitudinally along and into said ore bed.

6. As a means of igniting ore for sintering purposes, a perforated carrier for advancing an ore bed, a llame producing device, means below and acting throu h said carrier for drawin flames from sai device elongativel and longitudinally along the to of sai ore bed and progressively into said bed, and a hood including a refractory flame guiding and retainin wall above said flames and extending long1tudinally of said ore bed and rogressively delecting and retaining said ames, respectively toward and into enga ement with said ore bed in conso- .nance'wit the action of said means, where- 60 by ignition will be elfected with an increasing intensity.

. As ameans of igniting ore for sintering purposes, a perforated carrier for advancmg an ore bed, `a flame producing de- 65 vice, aA suction box below said carrier having a vertically restricted extension suction section acting through said carrier and ore bed for drawing llames from said device downwardly toward and along and into said ore bed to ignite and start combustion, said box 7 having an unrestricted suction section for drawin flames further into and longitudinall o said ore bed to advance the depth of com ustion previously initiated, and a hood including a flame delecting and retaining wall guiding the flame toward and against the ore bed, respectively, in consonance with the action of said suction box, whereby ignition will be effected with an increasing intensity.

8. As a means of igniting ore for sintering pu oses, a carrier for advancing an ore bed, a ame producing device, a suction box below said carrier and having a vertically restrictedv extension suction section acting through said carrier and'ore bed for drawing flames from said device downwardly toward and along and into said ore bed, said box having an unrestricted suction section for drawing said llames further into said ore bed, and a heat conservin llame deflectin and retaining wall extending in superpose relationover said restricted and unrestricted sections for deilecting and retaining the flames, respectively, toward and against the ore bed in consonance with the action of said suction box, said suction box extending beyond said wall in the direction of advance of said ore bed wherefrom air is drawn substantially vertically downwardly through said ore'bed to sustain and complete cornbustion.

In witness whereof, I have hereunto set my hand and seal.

ALFRED F. BEASLEY.

Images