US1551643A - Transportation and distribution of pulverized material pneumatically - Google Patents

Description

Sept. 1, 1 925.; I

J. CRITE S ET AL TRANSPGRTATION mi) DISTRIBUTION OF PULVERIZED MATERIAL PNEUMATICALLY Filed Oct. 11. 1924 4 Sheets-Sheet 2 pn lunn n lnn Sept. 1-, 1925.

1 J. CRITESI ET AL TRANSPORTATION AND DISTRIBUTION o,F PULVERIZED MATERIAL ENEUMA TIClALLY Filed Oct. 11. 1924' 4 Sheets-Sheet 5 "65 71 gel-Than: fares Se t. 1, 1925. 1,551,643

5 J. RITE'S ET AL TRANSPORTATION AND DIsTRiBUTIoN 0 PULVERIZEDIMATEIRIAL PNEUMATIGALLY w Filed 1;. 11; 1924 V 4 Sheets-Sheet .4

' Patented Sept. 1, 1925.

UNITED STATES PATENT OFFICE.

- JOE oRITEs, or EVANS'ION, ILLINOIS, AND BERTRAM :r. cRoss, or GLENWOOD SPRINGS, COLORADO, ASSIGNO'RS To INTERNATIONAL COMBUSTION ENGINEER- ING CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE.

TRANSPORTATION AND DISTRIBUTION OF PULVERIZED MATERIAL PNEUMATICALLY.

. Application ,filed October 11, 1924. Serial No. 743,123.

To all whom it may concern:

' Be it known thatwe, Jon Cairns and BERTRAM J. CROSS, citizens ofthe United States, residing at Evanston, in the county of Cook and State of Illinois, and Glenwood' an improved process and apparatus for subs dividing a stream ofthis material suspended III air, in such a manner that each divisionalstream will carry the same amount of solid material in proportion to the volume of air, per unit of time. Substantially the same device may be employed for retributors depending upon the grouping ofthe installation to be served. v

Each distributor is so formed as to subdivide the stream delivered thereto into a plurality of streams, each of which is drawn from substantially every portion of the cross-sectional area of the first stream, so that the density of all streams remains equal. lVe .here disclose two types of distributors, one of which will divide the first stream into a air of streams, and the other dividing the rst stream into three streams.

,By-a suitable combination of the required number of distributors of these two types, any desired number of subdivisions may be Obtained. a

More specifically, each distributor comprises means for dividing the streams fed thereto, into a multiplicity of similar small streams, and then distributing these numerous small streams among the two or more branch streams, in such a manner that thematerial delivered to the branches. is drawn from all portions of the main stream. For example, to supply two branch streams, each alternate subdivision of the main stream is directed into one of the two branches. For three branch streams, every third one of the subdivisions is directed into one of the branch streams. In this way, if any portion of the main stream is denser than other portions, by dividing this denser portion equally between the several branches, theddensity of the branches will be equalize By using such distributors at every pointwhere a stream of the material is divided or split into two or more branches, the density of the mixture will be maintained equal in every branch, and at every point of. delivery or consumption.

Also by placing one of these distributors at any intermediate point in a long pipe line, the several divisions of the material being fed back into the pipe, it will act as a reconditioner to reestablish an even den sity of the material throughout the crosssection ofthe pipe or conduit.

The above, and other objects and advantages of thisinvention will be apparent from the following detailed description of certain approved forms of apparatus suitable for carrying out the principles of this invention.

' In the accompanying drawings: F 1g. 1 1s a general diagrammatic view of one transporting and distributing system.

Fig. 2 is a similar View of another sys- .tem, involving the use of reconditioners.

Fig. 3 isan end view, partially broken away, of one of the two-way distributors.

Fig. 4 is a side view, partially-broken away, of this distributor. This view is taken looking from the left at Fig. 3.

Fig. 5 is a horizontal section, taken substantially on the line 5"5 of Fig. 4.

shown in Fig.8, looking from the left at Fig. 8.

Fig. 10 is a horizontal section,'taken substantially on the line 101O of Fig. 8.

Fig. '11 is a perspective view of one of the built-up deflecting units.

Fig. 12 is a perspective view of one of the division plates, used between the units shown in Fig. 11. f

Fig. 13 is a side elevation, showing one of the two-way distributors used as a re-conditioner in a single pipe line.

Fig. 14 is an elevation of the reconditioner looking fromtheleft of Fig. 13.

Fig. 15 is a similar view, partially in section, showing a pair of these distributors used for this purpose.

Fig. 16 is a similar view looking from the left at Fig. 15.

- Referring first briefly toFig. 1, a pulverizer is'indicated diagrammatically at 1, in which the material, coal, for example, is reduced to a powdered state and then forced pneumatically, in suspension in air, through a main conduit 2, At 3, 4, and 5 are indicated furnaces, each individual burner of which is fed through a separate supply conduit 6. The main conduit 2 connects with the several supply conduits 6, through a series of distributors and branch conduits, the arrangement and number of which will vary for different installations, and before proceeding further with the description of the general system we will describe in detail the improved distributor units used in this system.

Referring now to Figs. 3 to 7 inclusive, which show a two-way distributor, 7 indicates the feed pipe or conduit leading thereto, and 8 and 9 the pair of branch conduits leading therefrom.

-Where pulverized material is transported in suspension-in an air current throughaconduit whichhas elbows, angles or curved portions, centrifugal force tends to bring about an unequal distribution of the solids in the stream, transversely thereof, and this inequality in density tends to persist even after the stream has entered a straight section ofthe conduit. A similar condition of unequal density in 'difi'erent parts of the cross section of the stream may be brought about through the action of gravity in any 7 ortion of the transporting conduit which is not vertical. If the stream of air and solids under conditions such as these is divided, half, for example, being sent to one furnace or bin and the other half to another furnace or bin, the ratio of solids to air volumes is likely to be quite difierent in the two streams, and this is objectionablevfor obvious reasons, especially in the case of pulverized fuel fed directly to furnaces The distributors here disclosed provide a remedy for this difliculty.

Upper portions of the branch conduits 8 and 9 are widened out, as shown in Fig. 4, and their outer and inner walls made flat so that an angular ridge 10 is provided at the junction of the two branches, the branch pipes opening out of a common. section'll of the structure, which is preferably quite narrow in the plane of Fig. 3, and considerably broader in the plane of Fig. 4. \This section 11 preferably has a long and narrow rectangular cross section, such as indicated in Fig. 5.

Interposed between the branch conduit structure 11, just described, and main conduit 7 is a casing 12 in the form of a truncated pyramid having a circular flange por-' After entering the casing 11,this

deflecting plates 17 and 18, which are arranged in alternation in the space within structure 11 above the junction of branch conduits 8 and 9. The division plates 15 and 16 extend transversely of casing 11 in the direction of its narrower dimension. These socalled division plates 15 are flat plates formed with notches 19 in their lower edges, so that the plates fit over the angular ridge 10 at the junction of branch conduits 8 and 9. The division plates 16 are triangular in shape, with their pointed ends 20 extending downwardly in line with and against the ridge 10, and the deflecting plates 17 and 18 are preferably formed integrally with division plate 16, as right-angle flanges extending from the downwardly converging sides of these division plates 16. The rectangular extensions 21 at the lower'ends of the deflecting plates 17 and 18, are adapted to seat upon thesides of ridge 10. The dithese vertical passages 22, six leading to conduit 8, and six to conduit 9, but it is-to be understood that this is merely illustrative,

Suppose that the stream passing down through conduit 7 into the casing 12 is dense with solids on the right hand side of the con (luit, as viewed in Fig. 4, and. contains a muchsmaller'proportion of solids on the left hand side thereof. This denser mixture at the right hand side of the'distributor, will be split up between the several passages 22 at this side of the device, and distributed in substantially equal proportions to the two branches 8 and 91 The same will be true of the lighter material'in the left hand side of the device. Thatis, the stream is first spread out, preferably, so that it is, much wider in one direction than the other, and then is cut up into sections narrow enough, in the directionof the greater Iwidth of the main stream, so that when :thesedivided streams aresent alternately tothe branch conduits, each branch stream :will receive practically the same PIfOPOItlQIYOfSOlldS, no

matter how un'equal'may' be the di'stribu' tion of the solids-in the cross section of the main Strcann- Theresult is" that regardless of the inequality of distribution of the solids with respect to thecross-section of the main stream, each of the branch streams will carry approximately the same amount of solids per unit volume of air,-

As a matter of convenience, the casing 12 may be provided with an opening 23 for clean out and repair purposes, the opening being normally covered by closure 24.

In the three-way distributor shown in' Figs. 8 to 12 inclusive, the main conduit 7 and casing 12 are practically thesame as in the form previously described. The three branch conduits '25, 26 and 27 areeach flared out or made broader at its upper end, as indicated at 28, and the three conduits join with the lower portion of a casing 29, whose upper cross section, as indicated in Fig. 10, is quite similar in conformation to the corresponding section of the.casing 11 previously described. The junction of the flat portion of branch conduits 25 and 26 forms a ridge 30, and the junction of conduits 26 and 27 forms a ridge 31.

In this form of distributor, the dividing and deflecting members preferably comprise built-up. units such as shown at 32 in Fig. 11 wherein the narrow rec.- tangular open ended boxing 32 has end walls 33 and side walls 34, to which are secured thediagonally disposed ,defiecting plates and The widthof end plates 33 is substantially the same as that of thedeflecting plates 35 and 36, so that the width of the passage 37 through the boxing 32, will be substantially. the same as that of the passages 38 formed between the side plates 34, deflector plates 35 and 36, and the division plate 39, shown in Fig. 12, one of which is mounted between each adjacent pair. of the units shown in Fig.'11, The

width'ot plates 34and- 39 is substantially the same as the;distance between ridges 30 and 31, and ,the lower ends of the deflecting plates 35 and 36 are adapted to connect with the "ridges respectively.

It will be noted that each of the vertical passages 37 connect-with the branch conduit 26, whereas the deflectingpassages-38 (of'which there are twice as many as'ot the passages 37), are directed alternately into the branchconduits 25 and 27. In this manner, eachof'the branch conduits 25, 26 or 2'1, is fed from every third passagethroughout the length ofcasing 29. By making these passages 37 and. 38 suificiently narrow and numerous, substantially the same results are obtained, and in the same manner, with this "three-way distributor-{as with the two-way distributor previously described.-

l riYith slight structural changes, one or- Ino're'of these distributors can be used to recondition,.or render more homogeneous, a stream of material which has travelled for some distance through asingle conduit. As shown in Figs. 13 and 14, a single two-way distributor, 40 is positioned at some inter- ;mediate point inthe pipe line or conduit 41, the branch conduits 42 and 43 leading from IOU the distributor 40 being directed back into ,the continuation of the conduit 41. It will be noted that the branch pipes 42 and 43 are twisted relatively through about to avoidreturning the material to the same portions of pipe. 41 previously occupied by it. i

f shown in Fi s. 15 and 16, in which a pair ;o f two- way istributors 44 and 45 are posi- A more eiiicient device of this type is i tioned successively in the conduit at right angles to one another, so that the material will be successively split up in two different directions substantially at right angles to 'one another. In this form, the two branch pipes 42 and 43 may be omitted, and the "lower portion of the casing below the dividing walls, may be divided at right angles to these walls into .two halves by means of a vertical partition 46. The spaces at'the two sides of wall 46 correspond to the branch conduits 42 and 43in Figs. 13 and 14. Obviously' a three-way distributor. might be adapted to either form of reconditioner,

above described. c Referring now again to the installationindicated diagrammatically in Fig.1, the main conduit 2 is 'shown connecting with a threeway distributor A, which supplies the three branch conduits 47, 4 8 and 49. The branch conduit 47 leads to atwo-way distributor B,

which immediately feeds a pair oftwo-way distributors C and D, from the branches of.

.2 nected with main conduit, and in all of the other con-- which lead the four supply pipes 6 for the burners of furnace 3. As .illustrating a slightly ditl'erentconstruction, the. branch conduit 48 is shown connecting with a twoway distributor E from which. lead the branch conduits 50 and 51. 50 is shown leading to a two-way distributor F, positioned: near the furnace, which distributor feeds the two conduits 6 supplying two of the burners of furnace 4. In the same manner, branch conduit 51, through distributor G, supplies the other two conduits 6 for the other pair of burners of furnace4. The

furnace 5 is (illustrated as having three burners, the supply conduits6 of which are. fed from a three-way distributor. H con-.

the third main branch con-- duit 49. I

' In another typical installation, indicated in Fig. 2, the pulverizer 1 supplies powdered fuel to the burners offurnaces 3, 4-and 5, throilgh distributors A to H inclusive, and branch conduits 47 t051, as in Fig. 1. In this installation, conduit 2 being of'considerable length, a reconditioner M, of the type shown in Eigs. 13 and 14 is positioned in this conduit at an intermediate point to reestablish a more uniformly dense flow of the ma terial through the conduit.

p In the same manner, branch conduit 47 being of considerable length, a reconditioner N, this time of the type shown in Figs. 15 and 16, is placed at asuitable intermediate point in the run of pipe or conduit 47. Obviously the type of reconditioners shown at M and N could be interchanged or both might be of the same type.

Of course, the installations, are only examples of countless combinations that might be arranged. In every case, however, the density ,of the-mix ture of air and solids in each one of the conduits will remain the same as that in the duits, despite the fact that the mixture in any one or all of the conduits may not always be homogeneous throughout the cross-- sectional area of that conduit. While in the distributors illustrated, the branch conduits leading from each distributor here shown are of equal size and volume,

it is obvious that by suitably varying'the size of the sub-divisions in the distributor,

branch conduits of unequal size may be supplied therefrom. For example, if one branch conduit of a two-way distributorhas twice the volume of the other, the distributor would be 'formed with every alternate passage twice as lar e as those adjacent thereto. Similar resu ts could be obtained by arranging the deflectorfplates in the.

above described sample passages, so as to divert a larger number thereof, at properly spaced intervals,.to the larger branch condui i We claim:

1. In combination with a conduit for transportation of pulverulent material pneu- .ma tically, and a plurality .of branch conduits, means for dividing the stream of air and suspended solids passing through the main. conduit into a greater number of streams than the number of branch conduits and then directing certain of these streams into each branch conduit.

2. In combination with a conduit for transportation of pulverulent material pneumatically, means for dividing the stream of air and suspended solids passing through' the conduit into a plurality of streams and deflecting each alternate stream in'one directionand the other streams in another direction. p

3. In combination with a conduit for transportation'of pulverulent material inen-- matically, means for dividing the stream of air and suspended solids passing-through the conduit into a plurality of streams and) 'defleeting the divided streams angularly from the mainstream in alternation, one set of alternate streams from one side of the main stream and the other set from the other side.-.

4. In combination with a conduit for transportation of pulverulent material pneu-K matically, means-for dividing the stream of air and suspended solids passing through the conduit into a series of parallel streams," and a plurality of branch conduits, the divided streams from the main conduit being ,fed in'-. to the branch conduits in. successiveorderthroughout the series. .5. In combination with a conduitffor transportation of pulverulent material pneu matically, a portion of which is wider in a one direction than in the other, means, in said portion ofthe conduit for dividing the stream across its narrower dimension into'a plurality of streams, and for deflecting said divided streams angularly from the main. stream in alternation, oneset of alternate' streams. to one side, with respect tom. the

greater cross-sectional area of the main stream, and the other set to. the other side.

stream in series to form branch streams; r l a,

7. In combination with a main conduit for transportation of pulverized material pneumatically, branch conduits leading from themain conduit, andmeans-located a. plurality of at the junction of the main and branch conduits for dividing the main stream of air and solids and deflecting. the divided streams to the branch conduits so that the ratio of solids to air in the branch conduits is approximately uniform regardless of diiferences in density of the mixture in diflerent branch conduit being selected at regularly.

spaced intervals throughout the series.-

9. In combination with a main conduit for transportation of pulverulent material pneumatically, branch conduits leading from the main conduit, and means located at the junction of the main and branch conduits for splitting the mainstream into a series of substantially parallel streams, and deflecting these latter streams into the branch con duits, the streams deflected into any one branch conduit being selected at regularly spaced intervals throughout the series.

10. In combination with a main conduit for transportation of pulverulent material pneumatically, a portion of which is wider inone direction than in the other, branch conduits leading from said portion, and means in said portion for dividing the stream of air and solids across its narrower dimension into a series of smaller streams and for deflecting said divided streams into the branch conduits, 'the streams deflected into any one branch conduit being selected at regularly spaced intervals throughout the series.

11. In combination with a main conduit for transportation of pulverulent material pneumatically, a portion of which is wider in one direction than in the other, branch conduits leading from the wider sides of this portion, and means in the aforesaid portion of the main-conduit for dividing the stream of air and solids across its narrower dimension into a series of smaller streams and for deflecting said divided streams to said branch conduits, the streams deflected into any one branch conduit being selected at regularly spaced intervals throughout the series.

12. In combination with a main conduit,

for transportation of pulverulent material pneumatically, a portion of which is wider in one direct-ion'than in\the other, branch conduits leading from said portions,-one from each of its wider sides, means in said portion of the main conduit for dividing the stream across its narrower dimension into a plurality of streams, and deflecting said streams in alternation, one set of alternate streams into one of the branch eonduits and the other set into the other branch conduit.

13. In combination with a main conduit for transportation of pulverulent material pneumatically, aportion of which is wider in one direction than in the other, branch conduits leading from this portion of the main conduit, one from each of its wider sides, and a plurality of plates in this o1 tion of the conduit extending in the direction of the narrower dimension thereof, and

means arranged between said plates for defleeting the streams of air and solids into said branch conduits alternately.

14. In combination with .a main conduit for transportation of pulverulent material pneumatically, a portion of which is wider in one direction than in the other, a plurality of plates in this ortion of the conduit extendin in the direction of the narrower dimensions thereof, and means between said plates for deflecting the divided streams alternately to opposite sides of said conduit.

15. In combination With a main conduit for transportation of pulverulent material pneumatically, a plurality of plates in said conduit and means between said plates for deflecting the streams of air and solids between the plates alternately to opposite sides of saidconduit.

16. In combination with a conduit for transportation of pulverulent material pneu-' matically, a pair ,of branch conduits diverging therefrom and providing an angular ridge between them, a plurality of dividing and deflecting plates in the main conduit, the ends of which fit over saidridge and which are formed to divide the stream of air and solids and deflect the divided streams into said branch conduits alternately.

17. In combination with a conduit for transportation of pulverulent material pneumatically, a pair of branch conduits di verging therefrom and providing an angular ridge between them, a plurality of diportion of the main conduit extending across the same in the direction of the narrower dimension, and a plurality of deflecting plates between said dividingplates having oppositely inclined flanges on opposite sides to deflect streams of air and solids into said branch conduits alternately.

19. In combination with a conduit for transportation of pulverulent material pneumatically, a portion of which is wider in one direction than the other, a pair of branch conduits diverging from the main conduit at the wider sides thereof, and a third branch conduit substantially in line with the main conduit and between the two side branch conduits, a plurality of dividing plates in the aforesaid portion of the main conduit-extending across the same in the direction of the 'narrower dimension and forming a plurality of similar separate passages, these passages comprising three distinct series, each third passage belonging to the same series, adeflector plate in each passage of one series to deflect the suspended material into one side branch conduit, an oppositely disposed deflector plate ineach passage of the second series to deflect the material in the passages into the other side branch conduit, and a pair of parallel plates enclosing the othersides of each passage of the third series whereby the material therein is directed into the central branch conduit.

20. In combination with a main conduit for transportation of pulverulent material pneumatically, a portion of which has a rectangular crosssection, a plurality of substantially parallel plates in said rectangular portion extending across the conduit in' the direction of the narrower dimension thereof and forming aseries of passages amongst which the stream of material in the main conduit is divided, a plurality of branch conduits, and deflector plates in the passages for directing the material therein into some one of the branch conduits.

21. In combination with a mam conduit for transportation of pulverulent material pneumatically, a portion of which has a rectangular cross-section, a plurality of substantially parallel plates in said rectangular portion extending across the conduit in the direction of the narrower dimension thereof and forming a series of passages amongst which the stream of material in the main conduit is divided, a plurality of branch conduits, the passages being divided into as many series as there are branch conduits, the passages of each series being separated by passages of the other series, and similar deflecting means associated with each passage of any one series for directing the material in each of these passages into a certain branch conduit.

22. In combination with a main conduit 1,551,ees

for transportation of pulverulent material pneumatically, a portion of which has a rectan gular cross-section, a plurality of substantially parallel plates in said rectangular portion extending acrossthe conduit in the direction of the narrower dimension thereof and forming a series of passages amongst which the stream of material in the main conduit is divided, and means associated with the passages for directing the material in successive passages in different directions.

23. The method of subdividing a'flowing stream of pulverized material suspended in air, consisting in splitting the main stream into a series of similar parallel streams and then deflecting and combining alternate streams of the series to form one of the subdivisions of the main stream.

24. The method of subdividing a flowing stream of pulverized material suspended in air, consisting in splitting the main stream into a series of similar parallel streams, certain of these subsidiary streams being deflected and combined to form one of the sub divisions of the main stream, thesubsidiary streams of any one set being taken at spaced intervals from end to end of the series into which the main stream is split.

25. The method of subdividing a flowing stream of pulverized material suspended in air, consisting in causing the main stream to assume a relatively broad and narrow form,

splitting this portion of the stream at right angles to its broader dimension into a series of similar parallel streams, and then combining streams selected from spaced points throughout the series to form one of the subdivisions of the main stream 2G. The process which consists in pulverizing fuel, forcing a stream of the fuel suspended in air through a suitable conduit, splitting the stream into a multiplicity of similar subdivisions, selectively combining certain of the subdivisions to form an auxiliary stream, and delivering this auxiliary stream to a burner.

27. The process which consists in pulverizing fuel, forcing a streamof the fuel suspended in air through a suitable conduit, splitting the stream into a multiplicity of similar subdivisions, selectively combining certain of the subdivisions to form an auxiliary stream, splitting this auxiliary stream into a multiplicity of subdivisions, and selectively combining certain of these latter subdivisions to form a supply stream which is delivered to a. burner.

28. In a system of the character described, a source of pulverized material suspended in air, a main conduit leading therefrom, a plurality of burners, a separate supply conduit leading to each burner, and a combination of distributors and branch conduits between the main conduit and the supply conduits, each distributor comprising means for selecting the material delivered to each branch conduit from substantially all portions of the stream delivered to the distributor whereby a mixture of the same density will" be .furnished to each of the supply conduits.

29. In asystem of the characterdes'cribed,

a source of pulverized material suspended in air, a main conduit leading therefrom, a plurality of burners, a separate' supply conduit leading to each burner, and a combina tion of distributors and branch conduits between the main conduit and the'supply conduits, each distributor comprisingmeans for .and suspended solids passing throu h the main conduit, into a greater 'num er of streams than the n'umber of branch conduits and then directing certain of these streams selected from spaced portions of the main stream, into each branch conduit. a j

31. In a'system of the character described,

a source of pulverized material suspended in air, a conduit'leading therefrom, a plu rality of branch conduits, and a distributor connecting the main conduit with the branch conduits, the-distributorincluding means for selecting the material delivered to each branch conduit from substantially all'portions of the stream in the main con-- duit."

32. In a s stem of the character described,

a source 0 pulverized material suspended in air, a conduit leading therefrom; a plu- -branch conduits, the distributor comprising interspaced order with the branch conduits,

air, a'conduitleading therefrom, a plu-I rality of branch conduits, and a stationary distributing device connected with the main conduit and the branch conduits and comrality of branch conduits, and a distributor connectin the main conduit with the a -multiplicity of subdivisions connected in where y each branch-is fed equally ,from

substantially all portions of the main stream..

33. In a s stem of the character-described, a source 0 pulverized material. suspended prising means for dividing all portions of the main stream substantially equally between the several branches. v 34. In asystem of the character described,

a source of pulverized material suspended in air, a distributor,-a' conduit leading from the source tothe distributor, a plurality of branch conduits leading from the distribu-' tor, a plurality of distributors each fedby,

one of the branch conduits, and subsidiary branch conduits leading from each distribua v tor, each distributor comprising means for dividingfsubstantially allportions of the stream flowing thereinto' equally between the conduits leading therefrom.

35. In a system of the character described,

a source of pulverized material suspended in air, a distributor, a conduit leading from the source to the distributor, a plurality of branch conduits leading from the distributor, a" plurality of distributors each fed by .one of the branch conduits, and subsidiary branch conduits leading from each distribu: tor, each distributor comprising a multiplicity of subdivisions connected in interspaced order with the bran 2h conduits eading therefrom-.-

36. In combination with a conduit for the transportation of pulverulnt material pneumatieally, means .for redistributing the'sus-- pended-solidsin the stream of air passing through the conduit so; as toimake the stream more uniformly dense throughout the cr'oss-sectionalarea of the conduit, comprising a' plurality of division plates for dividingthe mainstream into a multiplicity of-branches, and means for collecting the branch streams and returning them to the conduit in a rearrangedorder;

- 3'7. The method of redistributing the suspended solids infthe'stream of air passing the stream into a multiplicity of divisions,

and then returning these divisions to the conduit in a rearranged. order.

38. In a system of the character described, a source of pulverized material suspended in air, a plurality of burners, a system of conduits and distributors for conducting the material from the source to the burners, and a devieemounted in one of the conduits for redistributing the mixture flowing therethrough so that a substantially uniform density ofthe mixture is obtained throughout the cross-sectional area of the conduit,

' said device comprisingmeans for separating ,through a conduit, consisting in separating the stream i'ntoa inultiplicity of .divisions,

and then'returning these divisions to the conduit in 'a'rearranged order.

In a system of the character described, a source of pulverized material suspended in air, a burner, a conduit for conveying the material iron), the source to the burner, and a device mounted at an intermediate posi- [tion in 'the' conduit for redistributing the mixt'ur'e flowing therethrough so that a sub-' stantially uniform density of the.mixtur'e is obtained throughout the-crosssectional area of the conduit,'said device comprising means for separating the stream into a multiplicity of divisions, and then returning these divisions to the conduit ina rearranged order;

JOE 'CRITES,

BERTRAM J. CROSS.

Images