US2003899A - Cleaning and sizing of coal - Google Patents

Description

June 4, 1935.

A. F. Nr-:sBlT 2,003,899

CLEANING AND SIZING OF COAL Filed Feb. 25, 1952 4 Sheets-Sheet l 67E THU/e F N555/ T,

June 4, 1935. A. F. NEsBlT 2,003,899

CLEANING AND SIZING OF COAL Filed Feb. 2s, 1952 4 sheets-sheet 2 lwena: 4E Hz/E F N555/ T,

June. 4, 1935. A NE$B|T 2,003,899

CLEANING AND SIZING 0F COAL Filed Feb. 23, 1932 4 Sh6`tSShee 3 [Quien/fof:

ffl/e THU@ F NESS/T,

@Mm @MM/ June Y* 4, 1935.

CLEANING AND Filed Feb.V 25, 1932 NEsBl-r 2,003,899

SIZING OF COAL 4 Sheets-Sheet 4 and method of cleaning and Patented June 4, 19435 UNITED STATES PATENT oFFlcE cLlniNT'NGfv AND sizrNG oF ooAL Arthur F. Nesbit, Wilkinsburg, Pa. Application February 23, i932, serial No. 594,641

Y 5 claims. (o1. 20a-137) This invention relates to the cleaning and sizing of lump and granular material such as coal, coke and the like, and has for one of its objects the provision of a novel apparatus for l sizing such materials. i

The present invention sizes the material, removes the fines and dust therefrom, removes the slate from the 'coal and sizes the material. v

One of the important advantages of the pres` ent invention is that all of the above described functions are performedwhile the material is drying and without the use of washers or other wet method steps heretofore generally used.

In the drawings:

Figure 1 is a vertical sectional elevation through an apparatus constructed in` accordance with thisinvention.y K

Figure 2 is an elevation partly in section taken on the line II-II of Figure 1.

Figure 3 is an elevation partly inV section taken on the line III- III of Figure 1.

Figure 4 is a sectional plan taken on the line IV--IV of Figure 1.

Referring more particularly to the drawings, which illustrate apparatus particularly adapted for the cleaning and sizing of coal, Athe numeral l designates a hopper to whichc'oal is delivered from any suitable source, such as the well known shaker screen. The hopper I` delivers the coal to a feeding conveyer 2 which discharges the coal upon a bar or other screen 3 in a chutell. The screen 3 permits thenes and dust of less than one-half inch mesh to pass through the screeny onto the bottom wall of the chute 4 While the coarse and lump material remaining yon the screen 3 passes down over a plate 3a to an adjustable feeder plate or lip 6. The bottom of the chute 4 on which the fines and dust are delivered is also provided with an adjustable feeder plate or lip 5. TheV feeder plates or lips 5 and 6 serve, respectively; to kill the downward velocity of the material sliding down the chute Ltand the material sliding over the screen 3 and plate 3i, and also to project the streams of material from the chute 4 and plate 3?' forwardly into oncoming and successively operating air streams or jets from suitable air nozzles n and n2.

j The air streams which are discharged from the nozzles n and n2`have a high velocity and serve to break up the material stream from the plate 3a and stream of fines and dust from the chute `li so as to carrythe dust and small mesh fines forwardly through the'chamber 'l and into a dust collector 8, Where the fines and dust are trapped in a dust-settling chamber 9. The air,

which is freed of substantially all of its dust,

returns from the dust collector 8 through'suitable conduits or pipes l0, D3, D4, D5 to a fan F.

The fan F delivers air through conduits or pipes 5v ber 9 is automatically discharged through a dust 10 seal 'I IL The impactvof the air jets against the coal streams from the feederl plates 5 and 6 gives rise to a wide range of trajections of coal of different sizes, resulting in sizing or separating of the coal of various sizes. 151

Attention is here called to the fact that the delivery of the coal over the screen 3 and plate 3a and of thefines over the bottom of the chute 4 causes a separation, so that the coarser material in both of the streams of coal is on the top and the fine material is on the bottom of thetraveling streams of material. As a result of the separation of the coarse and 4fine material of each of the streams of coal, the fines will be located on the sides of the streamsY as said streams are delivered across thejets of air from the nozzles n and nzopposite said nozzles so that as the air is projected into the streams of material the iines and dust may be readily blown out of the streams of material without the Vsplashing action ordinarily set up when `mixed streams of coarse and fine material are delivered across the air jets or where the material is delivered with the fines next to the air jets rather than on the side of the stream 35 farthest from the air jets.

The coarse material delivered from the feeder plate B will fall across the air jets from the nozzles n and n2, and any lines which have been formed by breakage or which have not passed through the screen 3 will be located on the side of the'stream of coal delivered from the feeder plate opposite the air jets, so that said nes will be forced forwardly to fall into the chute 23 to the right of the adjustable deector plate l2, while the coarser or lump material will fall into the chute 2| at the left of the The fine material and dust which is passed through the screen 3y and has V`moved down through the chute 4 and over vthe feeder plate 5 will be blown or forced forwardly by the air jets from the nozzles nv and n2 so that the heavierparticles of such streams will fall into the chute 24 to the right of the adjustable de- 55 ZW ,.-i

Iiector plate I3 while the ner material will be forced forwardly to the right of the deflector plate I4 so as to fall into the chute 25, where the very fine material and dust will be carried forward, as stated before, through thel chamber 1 to be trapped by the dust separator 8.

The position at which the adjustable deflector plates or baiiles I2, I3 and I4 are set will control the coal sizes that fall into the several chutes 2|, 23, 24 and 25. The coal, which is passed to the level of the deflector plate I2 so as to fall into the chute 2|, first passes over successive baffles I6, I1 and I8 so as to slow up the flow of this coal, and a suitable bar,

screen or the like I9 is arranged in the "chute 2| so as to separate any fines produced Vby breakage from the main flow body or stream of coal passing through the chute 2|, yThe fines passing through the screen I9 are delivered into a chute 20, from Which they may be deliveredto any point of storage or consumption.

The coal which flows over the screen I9` and through the chute 2| passes down into a chute 22 which forms a continuation of the chute` 2|. The coal is discharged from the chute 22 over an adjustable feeder plateV or lip 2,6 and plunges or moves forward and downwardly through cooperating air jets or streams issuing from a pair of nozzles 113 and 115. coal stream from the chute 22 is adapted to be sized in the chamber 21 by means of the air jets from the nozzles 113 and n4, and the spent air, after passing through this coal stream, is delivered through a conduit 28 to the conduit section D3, to be returned to the'fan F.

The sizing of the coal in the chamber 21 depends upon the setting of the dampers 58 and 59, the setting of the nozzles 113 and n4 and upon the setting of the baffle plates 29, 30 and 3| at the tops of the chutes 38, 49, 4| and 42. The heavy and coarser material passes from the feeder plate 26, drops through the air 'jets from the nozzles 113 and 114 into the chute 38 and successively smaller particles of material are delivered to the successive chutes 40, 4|\ and 42. Each of the chutes 49 and 4I are provided at their upper ends with bars or other screens 43 and 44, which serve to separate any fines caused by breakage of the material entering the chutes, and these nes are trapped in suitable chutes 45 and 46 to be delivered out of the system to any suitable point of disposal. The baffles I2, I3 and I4, previously described, and also the bafIies 29, 39 and 3|, are adapted to be set at such inclinations to the trajections followed by the coal in its flight in the respective chambers 1 and 21 as to slow up as little as possible `the velocity of the pieces or particles of coal. In fact, these bales are adapted to be so set as to encourage sliding at the instant of impact so as to minimize the breaking of coal due to striking against the bales and chutes.

The chute 39, in which the heavier and larger particles or pieces of coal have been segregated in the last sizing'operation, is provided with suitable baffles 33, 34 and 35 to slow up the travel of the material as it enters the chute, and a suitable bar or other screen 36 is provided to separate the nes caused by breakage of the material as it enters the chute 38. The fines passing through the bar or screen 36 enter a chute 31 which is adapted to deliverv such fines out of the system to any point of disposition desired. The chute 38 connects with a chute 39 which terminates in a feeder plate 41.

The

In actual operation, the coal delivered overv the feeder plate 41 will consist of practically all lump or large particles and will be projected forwardly into the path of the air jets from the nozzles and 115. The coal delivered through this chute 39 will contain the usual amount of cubicle and flat slate and also pieces of slate and bone with coal adhering thereto, as is commonly found in mined coal.

The feeder plate 41 is so inclined, and the nozzles 11.5 and 11,5 are so directed that the air jets from the nozzles 115 and 11.6 will cut across the flat pieces of slate edgewise as such slate leaves the feeder plate 41 so that said slate, due to its weight, rwill plunge through the air jet and fallinto the slate or refuse receiving container 5I; The cubicle pieces, as well as much of the bone, and any other foreign matter having greater weight than'the coal, will also cut through the air jets and fall into the container 5|.Y A suitable deflector or baille plate 59 is provided at the upper end of the refuse container or bin 5| so as to provide for adjusting the width of the top or entrance portion of the container 5| to insure the trapping of all of the slate, bone and other refuse. The coal will be blown forwardly by the air jets from the nozzles 115 and 116 so as to strike against an adjustable baffle 53 and be trapped in the container or bin 52. As the coal enters the bin 52 fromthe baille 53 it will pass over a bar or screen 54 which will remove any fines caused by breakage, which fines will be trapped in a container 55.

Suitable dampers are provided in the conduit branches leading to each of the respective nozzles,'which dampers are adapted to be adjusted to determine the amount of air delivered to, and therefore the impact of, the air jets upon the material. The damper controlling the lower air jet of each set of air jets is preferably adjusted to provide an air jet of less velocity than the upper air jet so that the material will size more accurately by gravity.

Each of the chutes 23, 24 and 25, and 40, 4| and 42, in which the various sizes of material or coal `are collected, are adapted to terminate at their lower ends in a slate and refuse removing unit of duplicate construction to the unit last described, such units being offset to one side of the apparatus as indicated in Figures 2 and 3 of the drawings, and being indicated in Figure 2 by the numbers 235, 245, 255 and 405, 4I5 and 425, respectively.

It will be understood that the slate and refuse collecting chambers 235, 245, 255 and 405, 4| 5 and 425 will each be provided with nozzles as in the chamber 48, and that these nozzles will be connected by branch conduits to the conduits D1 and D2, respectively, and will have their discharge ends connected to the conduits D3 and D4, respectively, so as to form a recirculating system of air through said refuse collecting chambers.

The apparatus and method of this invention has many advantages over apparatus heretofore in use for the cleaning and sizing of coal, and other granular and lump materials, since the apparatus has no moving parts and an enclosed and recirculating air system is provided so that no dust escapes into the atmosphere and no coal is lost. ThisY is an entirely dry system and eliminates the mud and sludge which form a necessary evil of wet or washing systems heretofore generally. used. Since no 'water is used in the present method, the necessity of evaporating water after cleaning the coal, as is necessary with the wet methods, is eliminated and the handling of the coal is facilitated.

In the present method the dust is collected and may be used as a powdered fuel.

While I have shown and described one specic embodiment of apparatus for carrying out my novel method and a certain sequence of steps of my novel method, it will be understood that I do not wish to be limited thereto, since various modiiications may be made without departing from the scope of my invention, as defined by the appended claims.

I claim:

l. In a cleaning and sizing apparatus for lump and granular material, an enclosed inclined conveying chute for conveying the material to be sized and cleaned, upper and lower material conveying walls in said chute, said upper wall being composed, at least in part, of a screen through which the fine material and dust passes onto said lower material conveying wall, angularly adjustable deector plates at the discharge ends of said conveying walls in the path of travel of the material under treatment and adapted to arrest the flow of the material and to cause said material to discharge from said chute into space with substantially no initial downward velocity, and means for producing a plurality of relatively high velocity air jets directed upwardly and forwardly into the material as it is discharged from said chute and below the deiiector plates, said air jets being adapted to separate the fines and dust from the heavier material delivered by said chute.

2. In a cleaning and sizing apparatus for lump and granular material, an inclined conveying chute for conveying the material to be sized and cleaned, upper and lower material conveying walls in said chute, said upper wall being composed, at least in part, of a screen through which the fine material and dust passes onto said lower material conveying wall, angularly adjustable deilector plates at the discharge ends of said conveying walls in the path of travel f the material under treatment and adapted to arrest the flow of the material and to cause said material to discharge from said chute into space with substantially no initial downward velocity, and means for producing a plurality of relatively high velocity air jets directed upwardly and forwardly into the material as it is discharged from said chute and below the deector plates, said air jets being adapted to separate the nes and dust from the heavier material delivered by said chute, said chute being inclined downwardly and toward said air jets so as to deliver said material to said air jets with the ne material and dust localized on the side of the material streams opposite said air jets.

3. In a cleaning and sizing apparatus for lump and granular material, a chute inclined to the vertical for conveying a flat, single layer stream of the material to be sized by gravity, a substantially horizontal angularly adjustable deflector plate at the discharge end of said conveying chute in the path of travel of the material under treatment and adapted to arrest the flow of said material and to cause said material to be discharged from said chute into space with substantially no initial downward velocity, and in a substantially horizontal plane, means for producing a plurality of high velocity air jets, said means including a plurality of vertically spaced upwardly inclined air nozzles, said nozzles being so arranged and adjusted as to direct said air jets upwardly into said material as it is discharged irom said chute and below the deflector plates so as to force the smaller and lighter material forwardly until said material falls out of the path of said air jets by gravity, and means for controlling the flow of air through said nozzles so that the successive air jets will have slightly less velocity than the preceding jets to permit the material to size by gravity, means for receiving and maintaining said sized material separate, means for collecting the air from said air jets and means for recirculating said air through said jets.

4. In a cleaning and sizing apparatus for lump and granular material, means for conveying relatively thin and slow-moving streams of material to be cleaned and sized and for separating the same into parallel streams of coarser and ner material respectively, at least two air nozzles directed upwardly and forwardly so as to direct jets of air of a relatively high Velocity across the paths of the streams of material discharged by said conveying means, said conveying means causing the material to be moved by gravity toward said air nozzles and to discharge said material immediately above the jets of air from said nozzles and localizing the fine material and dust on the side of the material Vopposite from said air nozzles, the jets of air from said nozzles passing through said stream of material and removing the fine material and dust, and means for providing a suction on the side of said stream of material opposite said air jets to withdraw said dust laden air.

5. In a cleaning and sizing apparatus for lump and granular material, an enclosed conveying chute for conveying the material to be cleaned and sized, said enclosed conveying chute being inclined downwardly so as to permit the material to move over its entire length by gravity alone, said conveying chute being constructed and arranged for an entirely uninterrupted flow of material and provided with means to separate the material into streams of fine and coarse particles respectively with the fines on the bottom wall of the chute, and means for producing at least one high-velocity air stream, said conveying chute being arranged to deliver the material ARTHUR F. NESBIT.

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