US1453850A - Method of and means for burning bricks - Google Patents

Description

May 1, 1923.

G. E. LUCE METHOD OF AND MEANS FORBURNING BRICKS Filed July 25 1917 3 Sheets-Sheet l wn an @n 8 Gwagiavul? l-ZZCQ/ w May-l, 1923. 1,453,856

G. E. LUCE METHOD OF AND MEANS FOR BURNING BRICKS Filed July 25 1917 3 Sheets-Sheet 2 May 1, 1 923 1,453,850

G. E. LUCE 1 METHOD OF AND MEANS FOR BURNING BRICKS Filed July 25 [1917 s Sheets-Sheet 5 C(iifozmeys Patented May 1, 1923.

UNITED STATES GRAFTON E. LUCE,

OF CHICAGO, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS, T0

CHARLES A. BROWN, OF HINSDALE, ILLINOIS.

METHOD OF AND MEANS FOR BURNING BRICKS.

Application filed July 25, 1917. Serial No. 182,653.

T 0 all whom it may concern:

Be it known that I, GRAFTON E. Loon, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Methods of and Means for Burning Bricks, of Which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to a method of and means for burning bricks. This invention is an improvement upon a process of burning bricks known in the art as the Lambert process. In that process a generally horizontal zone of heat is created in the lower part of the kiln at a rapid rate so as to drive off the moisture from the bricks faster than the kiln draft will carry the same off so that finally the draft becomes choked and the heat which has been put in the bottom of the kiln is held there and is not dissipated by leakage of air or by any draft.

The present invention is particularly concerned with an improved manner of generating the heat in the bottom of the kiln; in an improved manner of applying and burning fuel in the kiln, and in an improved manner of causing the heat which is gener ated in the lower part of the kiln to be moved through the unburned part of the kiln to finish the entire kiln.

Further objects of the invention are to provide an improved structure of kiln for carrying out the various steps of the process and a new relation between a particular type of firing apparatus and a brick kiln.

Other incidental and contributory objects will be apparent from the following specification, which, together with the drawings which form a part of the same, describe one particular manner of practicing and constructing my invention so that those skilled in the art may fully understand the same.

Figure 1 is a cross sectional view of a kiln of bricks with parts broken awaywith the burning apparatus applied in position to create a zone of heat in the lower part of the kiln. This section of Figure 1 is taken through an arch of the kiln.

Figure 2 is a similar view showing the blower pipe in position during the stage of blowing.

Figure 3 is a fragmentary section taken on the line 8, 3 looking in the direction of the arrows showing the disposition of the blower pipe in the lower furnace and showing the relative arrangement of dog-house and arch.

The bricks are preferably formed with a compact exterior and somewhat less compact interior which will permit of rapid firing without damage. The bricks are then set into the kiln for burning. The bricks may' be formed in any other desired manner, as

this feature forms no part of the present invention. The type of kiln which I prefer to employ is the scoved kiln although it is to be understood that the invention is applicable to other forms of kilns. In building a kiln, a bed or foundation of previously burned bricks three layers deep, as shown by th reference, numeral 1 is first laid down fiat on the ground. This layer of burned bricks l is interrupted to form a space or furnace 2 substantially three bricks thickness deep and about 3; of a brick length in width extending ompletely across the kiln. This furnace is closed off at the top by a series of burned bricks being placed close to each other with small spaces between them. They are set, however, substantially in contact with each other. The bricks .to be burned are then piled on top of the lower layer 1 with arches formed over the furnaces 2 and the bricks 3. The dried bricks which are to be burned may be handled by cranes or in any other manner. If a crane is employed the bricks are taken from the driers on cars piled eight brick widths deep and the cranes pick up a carload at a time and place it in the proper position for building up the kiln.

A crane load of bricks is set on each side of the burned bricks 3 resting upon the foundation of burned bricks 1, as shown .in Figure 3. This leaves an opening Which becomes the arch opening forming a furnace above the furnace 2 and communicating with the furnace 2 by means of the spaces 4: between the bricks 3 as well as through they crevices between the green bricks 5at the bottoms of the arches and the burned bricks 1 which form the foundation.

The workmen with their hands draw the upper layers of bricks over to form ets 6 and thus close off the tops of the arches 7. After the arches are formed the spacesbehind the jets are filledin with extra bucks placed by hand as shown at 8. To complete the kiln the unburned bricks are packed on top of the bricks thus set by means of the crane where the same is our ployed until the kiln is completed.

I prefer to form the kilns of about 22 arches set 48 courses high measured in brick widths exclusive of the bottom bricks 1. The width of the kiln at the bottom is about 5% brick lengths and at the top is about 51 brick lengths. Each pillar or leg between the arches has a horizontal thickness or about four brick lengths and each arch is about 2 brick lengths in width so that the consecutive arches are about six brick lengths distance from center to center.

The bricks all stand on edge cries-cross with narrow spaces between them with a spacing of about3 over 1.

On the outside of the kiln above the arches and on the ends of the kiln from the ground up there is placed a wall 9 of double coal bricks, the thickness of this wall being equal to thelength of a single brick. The double coal bricks in this wall are made up by mix ing coal screenings preferably anthracite coal with the clay in the proportion of about 80 lbs. to a thousand bricks.

Outside of the double coal brick wall 9 a wall of previously burned bricks 11 is built up all around the sides and end of the kiln.

his wall 11 has a thickness of a brick length for the lower half and has a thickness of a single brick width for the upper half. The outside of the wall 11 is then daubed over or scoved with a daubing made of sand and loam so as to close the cracks between the bricks. On top of the kiln a layer 12 of previously burned bricks which is called the platting or fiattino; is laid with the bricks lying on the side. These bricks are laid closely but are not scoved or daubed and the cracks or fissures between them permit the gases and vapors from the kiln to escape.

The outside wall 11 of burned brick is built across the upper part of the ends of thearches 7 as can be seen at 13 in Figs. 1

and 2, but so as to leave openin s to the exterior along the lower parts of the arches 7. Extensions 14 called dog-houses are built out from the open end of the side wall 11 in line with the arches.

Above each dog-house a peep hole 15 is left in the wall 11. this peep hole being normally closed by a brick bat.

The side and end walls of the kiln may be suitably braced as desired.

Some means is preferably provided for indicating the settle. This may consist of a rod or finger normally touching the top ot' the platting or a pile of brick bats on top oi the platting as for instance a rod hung fron. the roof or frame work of the shed, the end of the rod just touching the flatting or a pile of brick bats on the fiatting so that when the settle begins a space will show bet-ween the end of the rod and the top of the kiln.

F or the purpose of heating the bricks for firing the same I provide a horizontal burner nozzle 16 at each end of each arch. This nozzle comprises a horizontal tube terminating in a restricted tip or jet 17 having a conical flange 18 about the same. A pipe 19 adapted to deliver powdered coal in proper quantities communicates with the nozzle 16 by way of an opening 29 above which the pipe 19 is adjustably secured. The pipe 19 telescopes with a pipe 21 from which it is supported and to which a supply of powdered coal is furnished. The adjustment of the pipe 19 may be fixed as by means of the thumb screw 22. The opening has a flange 27 about the same to insure catching of the stream of powdered coal from the pipe 19, and to admit air which is drawn in by the blast which is supplied to the nozzle 16 from any convenient source. The blast of air in the nozzle 16 may be generated by means of a fan, a rotary blower, by a steam jet entraining air or other well known means.

F or the purpose of blowing in air at a certain pressure in carrying out the latter part of the process of my invention as 1 shall describe hereafter, I provide a blower pipe 23 which consists of a straight length of pipe extending from end to end of the space 2 and having openings 24: substantially evenly distributed across the width of the kiln for blowing air under pressure into the kiln as will be described presently. The end of the nozzle 16 is adapted to register with the open end of the blower pipe 23.

The pipe 28 may consist of one continuous piece from side to side of the kiln or may consist of separate parts inserted from each end and furthermore the section of the pipe may be decreased to take care of the different amounts or quantities of air flowing therethrough.

I shall now describe the manner of firing the kiln in the manner previously described. The nozzle 16 is directed into the lower furnace2 which has its walls made up entirely of burned bricks. A blast of air is then directed through the pipe and at the same time the proper quantitv of powdered coal is fed through a pipe 19 and these two elements unite in a stream or blast in the nozzle 16 which is directed into the lower furnace 2. The blast of powdered coal and airis ignited as by means of a shovel full of live coals, a piece of burning oil soaked waste, or the like.

The powdered coal is of a fineness such that approximately 85% will pass through a 200 mesh screen and 95% through a 100 mesh screen. The powdered coal is retained in a very dry condition having only about 1 per cent moisture.

The fire is directed into the furnace 2 from each end thereof with as great a force as is required to fill the furnace. This burning is continued for about 2 hours and at the end of that time the entire furnace 2 will be heated across the length of the arch. The bricks 1 and the layer of bricks 3 will be red hot and the adjacent green bricks 5 will have been dried off and partially burned by this preliminary heating of the burner 2. The face of all the bricks facingthe inside of the arch will also have been dried off so that at the end of this time the arch is thoroughly dry and the legs or benches'will have a preliminary drying which will permit them to be burned very rapidly.

The advantage of burning in a furnace of burned bricks is that the fire burns clearer and hotter from the very beginning and there is no tendency for the ash or particles of coal to adhere to the walls. After the furnace 2 has been properly heated up so as to dry off the furnace which is formed by the arch 7, the nozzle 16 is raised into the dotted line position 26 shown in Figure 1, the pipe 19 being raised and fixed in position to correspond and the flame is then directed into the furnace 7 above the furnace 2.

The fire 'is then directed to heating the arch completely across the bottom of the kiln to substantially a brick-burning heat in the neighborhood of 2000 degrees F. The advantage of the coal burning apparatus heretofore described is that no outlet or regular draft is necessary as is the case where lump coal is burned. It is possible to burn the powdered coal under a very considerable pressure in a substantially closed place so long as the blast is maintained. This is due to the fact that the-blast which carries in the fuel is also sufficient to form a complete combustion of the fuel thus carried. In order to burn powdered coal a very considerable length offire box is necessary and this is completely and adequately provided in the arches by the furnaces 2 and 7.

The fire is first directed to igniting the double coal bricks 9 and then to heating the arch evenly throughout its entire length. This isaccomplished in about 16 hours of burning.

The condition desired by the burners is to secure an even heat in a continuous zone throughout the entire bottom of the kiln, this zone rising slightly at the edges where the double coal bricks 9 have been ignited.

The fire is forced to such an extent and must be forced to drive off the moisture of the bricks faster than the kiln draft will carry it off so that the top of the kiln finally becomes choked with steam. forming what I term a blanket of steam. The formation of the blanket of steam together with the pressure generated by the nozzle venience is occasioned by the ash.

16 tends to insure the creation of the isothermal zone in the bottom of the kiln. The employment of the powdered coal as fuel is not detrimental as might be expected because of the very fact that the kiln draft has been shut off by this choking with steam and as a consequence the ash does not pass up through the stack and settle upon the green brick but instead is trapped in the relatively dead air space in the arches or furnaces 7 so that practically no incon- The ash is not driven from the top of the kiln and consequently no objection can be made to burning bricks in proximity to dwellings or other buildings.

At the end of about 16 hours the operator can notice a slight settle at the top of the kiln, this settle being substantially even entirely across the kiln if the fire has been in is suflicient to fill the bottom of the kiln taking the place of the air previously heated and expanded by combustion and at a pressure sufficient to overcome the resistance of the blanket of steam in the upper. part of the kiln. This blast of air levitates or raises the blanket of steam forcing it up at the top of the kiln and at the same time it carries upward the heatunder the blanket of steam thereby finishing the bricks in the strata above. This blowing is continued until the zone of heat is carried upward under the blanket of steam to the very top of the kiln and then out. At this point the blowing is discontinued.

It is to be noted that the initial blast of cold air does not strike the heated bricks which are being burned for the first time but strikes only the heated bricks 1 and 3 which were previously burned and which are not subject to cracking. The blast of air finding its way to the narrow openings and crevices betweenthe bricks 3 and between the bricks 1 is heated sufficiently that it does not chill the bricks 5 around the'arches and consequently there is much less danger of cracking or damaging any of the bricks in the arches or other parts of the kiln.

The result of this blast of air is to levitate or raise the blanket of steam forcing it out of the top of the kiln. As the blanket of steam is raised the heated zone is carried upward and as the blowing continues the heated zone travels throughout therestof-the kiln to the top of the same and burns the bricks to the desired degree as it passes. When the wave or zone of heat has reached to top of the kiln the bottom of the kiln is practically cool enough for handling. This blowing continues for about 2% more hours making the total time of burning in the neighborhood of 40 to 48 hours from the beginning of burning.

The fuel cost is very low because of the short period during which burning is carried on and because of the low cost of powdered fuel.

After the blowing has been completed, that is, after the zone of heat has traveled to the top of the kiln, the dog-houses are knocked down and the air is allowed to enter to cool off the kiln. As a result the kiln may be taken down and hauled away very shortly.

In firing the kiln it is essential to observe the following condition. The firing must be rapid enough and must be distributed over sufficient bricks to evolve the blanket of steam. Otherwise the heat will escape by the kiln draft and will not be available for blowing.

At the same time sufiicient bricks must be heated so that they contain a large enough body of heat to finish the rest of the kiln. With these conditions observed burning of a kiln of bricks is under the absolute control of the operator at all times.

The arches or furnaces provide large free space within which the flame from the powdered fuel may be developed. The formation of the blanket of steam which shuts off the draft does not prevent the burning of the powdered fuel as it is supplied with its own air for supporting combustion, and hence does not require any definite draft as would be the case in burning lump fuel.

The extent of the fire may be restricted and the fuel consumption may be restricted and at the same time the pressure in the kiln which contributes the heat may be re tained merely by the addition of a surplus of air. Thus it is possible within the furnaces, that is within the arches to vary the total amount of heat generated without varying the pressure which is necessary to distribute the heat. This is of very great importance in obtaining the heated Zone in the lower part of the kiln.

When the fire is directed into the furnace 7 it is to be noted that no separate fire boX is necessary and the heat is intimately distributed among the bricks and directly applied. The arch thus serves the double function of permitting the generation of a long flame and of being a place for the depositof the ashes which settle due to the lack of upward current. A further advantage over the burning of lump coal is that the direct radiation from the fire which results in burning lump coal is distributed throughout the length of the flame in my process and hence the bricks directly at the ends of the arches are not overburned before the heat can be driven through the interior of the kiln.

The fire may be forced from the very beginning on account of the distributed nature of the same and this tends to secure quick and even burning.

In burning according to my method and employing powdered coal, there is practically no draft in the arch or furnaces proper, therefore none of the ash of the powdered coal would be carried up into the kiln where the bricks are green and this prevents any choking of the kiln with ash or any detrimental effect on the coal before or at the time of burning.

I claim:

1. In a kiln, a stack of green bricks and a foundation of burned bricks, said foundation of burned bricks having a furnace therein and said stack of green bricks having a furnace therein adjacent the furnace in the foundation, said furnaces being connected at intervals through a foraminous wall of burned bricks.

2. In a kiln, a transverse arch of green bricks, and a transverse furnace of burned bricks lying parallel with said arch and communicating through spaced relatively narrow slots with said arch.

3. In a kiln, a foundation having a transverse groove therein, forming a furnace within which to burn fuel, a series of bricks set on edge over the top of said groove partially closing the same off and an arch of green bricks set over said groove and communicating with said groove through the interstices between the bricks set on edge and through the interstices between the bricks in the foundation.

4:. In a kiln, a foundation having a transverse groove therein, a series of bricks set on edge over the top of said groove partially closing the same off and an arch of green bricks set over said groove and communicating with said groove through the interstices between the bricks set on edge and through the interstices between the bricks in the foundation means for burning fuel in said groove and in said arch and a pipe adapted to be inserted in said groove, said pipe hav ing means for creating a blast of air and having a plurality of openings for discharging said blast at a plurality of points along said groove. said pipe being adapted to be put in communication with the means for burning fuel.

5. The herein described method of burning bricks, which consists in forming a kiln of the bricks with a main transverse arch at the bottom, and a secondary arch or furnace below the main arch formed of burned bricks, introducing combustible fuel into the secondary arch of a kind and in suflicient quantity to very rapidly raise the temperature of the walls of the secondary furnace to a high temperature, approximately 2000, Fah.,,thereby applying heat to the bricks forming the walls of the main arch with sufiicient rapidity to thoroughly dry them preparatory to burning in such a short time as to form a steam blanket in the upper part of the. kiln, thenvintroducing fuel into the main arch to burn the lower part of the kiln, then introducing air into the secondary furnace in sufiicient quantities to levitate the apart to form narrow communicating slots;

8. In abrick kiln, 'a transverse arch'of green bricks, a furnace extending longitudinally beneath the arch in which to burnfuel, the wall between the furnace and the arch provided with narrow spaced slots whereby the arch bricks are protected from the intense heat developed in said furnace.

9. In a brick kiln, an arch of green bricks,

a furnace of relatively small cross section extending longitudinally beneath said arch, a wall of burned bricks substantially conlining the heat of combustion to said furnace, said wall being provided at intervals with narrow slots for-the escape of the products of'combustion from the furnace to said arch. I

10. In a brick kiln, an elongated furnace adapted to have fuel projected into same from both ends, an arch of green bricks extending above the furnace, and'an archfrom the arch, said floor formed of bricks resting attheir ends on the side walls of the furnace and spaced slightly apart, forming narrow communicating slots between the;

I furnace and the arch above same.

11. The method of burning brickswhich comprises introducing heat at a predetermined place in a foraminous pile of bricks, and after the surroundings of the heated place have been heated to a predetermined degree, transferring the heating to another location in the surrounding heated zone having more extensive communication withthe entire pile.

floor of burned bricks, dividing the furnace 12. The method of burning bricks with powdered fuel without choking the kiln, which comprises building a. small furnace below a large furnace, heating by means of the small furnace until the walls of the large furnace are'hot enough not to collect soot from thezones of incomplete combustion in the flame, and then transferring the heating to the large furnace.

13. The method of burning bricks, which comprises building a small furnace adjacent a large furnace, burning the large furnace partially by heating the small furnace, burning the lower part of the kiln by heating the large furnace, and burning the upper part of the kiln by blowing air through the lower burned portion to carrying the heat up.

comprises building a small furnace adjacent a large furnace, burning the large furnace partially by heating the small furnace,

.burningthelower part of the kiln by heating the large furnace, and burning. the up- [per part of the kiln by blowing air through the lower burned portion to carry the heat up, said air being introduced into the small furnace, to avoid damageto the bricks formingt-he large furnace by too sudden cooling.

-In witness whereof, I hereunto subscribe my name this 20th day of July, A. D. 1917. I a GRAFTON E. LUCE.

I i 14:. The method of burning bricks, which

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