USRE21682E - Apparatus for separating and clean - Google Patents

Description

h APPARATUS FOR SEPARATING AND CLEANING MATERALS Original F-iled July 29, 1932 3 SheetsPSheet 1 De.31, 1940. E STUMP Re. 21,682 AP-PARATUS FOR SEPARATING AND CLEANING MATERIALS OriginalA Filed July 29, 1952 3 Sheets-Sheet 2 Dec. 3,1, 1940. 'E S'TUMP Re. 21,6132i APPARATUS FOR SEPARATING AND lCLEANING MATERIALS Original Filed July 2 9, v1932 v 5 Sheets-Sheet 3 In 'V672' for' f! www Reissued Dec. 3l, 1940 .UNITED STATESv PATENTl ori-'lcs APPARATUS FOR SEPARA-TING AND CLEAN-r ING MATERIALS Earl Stump, Harvey, Ill., assignor to Roberts and Schaefer Company, Chicago, lll., a corporation of illinois Original No. 2,086,584, dated July 13, 1937, Serial No. 625,767, July 29, 1932. Application for reissue July 8, 1938, Serial No. 218,253

11 Claims.

eration through a relatively wide range of siz-` ing, thereby dispensing with the necessity of excessive preliminary screeningv v Another object is to provide a material separating device which will be simple, light, inexpensive, of largecapacity, take up a minimum of room, andl have a minimum of vibration, whereby it becomes unnecessary to build special reinforcing or stiffened buildings or structures to house the same. Other objects of my invention will appear from time to time throughout the specification andclaims.

My invention is illustrated more or less diagrammatically in the accompanying drawings, wherein Fig. 1 is a side elevation;

Fig. 2 is a plan view;

Fig. 3 is a section along the line 3-3 of Fig. 2;

Fig. 4 is a section along the line 4-4 of Fig. 2;

Fig. 5 is a detail of the butterfly valve drive;

Fig. 6 is a diagrammatic view of a variant form of blower or pump; and

Fig. 7 is a modified form of the device.

Like parts are indicated by like characters throughout the several figures.

A is an lair chamber. It has a bottom AI, end walls A2, A3, side Walls A4. the top by a perforate Wall A5. A6 is an air duct discharging into the chamber A. Air is supplied to it and discharged therethrough by a fan or other suitable source of air under pressure Al. The fan is driven by a motor All in `the usual manner. A9 is a butterfly valve interposed in the duct A6 between the fan land the chamber. AHI is a power transmission interposed between the motor and the buttery v-alve which may be of any suitable form but preferably is adapted for easy and convenient speed adjustment so that'the revolutions per minute of the butterfly valve may 'be conveniently and easily adjusted during operation of the machine.

Mounted on top of the air chamber A and between the side walls A4 which project upwardly above the chamber is a fixed resistance bed B. formed preferably of screened gravel, shot,

sawdust, mineral Wool, or any suitable material.v

It ls bounded at I This resistance bed is bounded at its upper side by a perforate screen or deck BI. The deck BI is inclined to the wall A5 so that the thickness of the air resistance bed or filter decreases 4from one end to the other. The perforate plates BI and A5 are xed in position and so related with the resistance bed that ythe material therein remains at rest and furnishes at all times a fixed unchanging internal resistance bed to control the rate at which air escapes from the chamber A and soytocontrol thev pressure of air availlocated beyond the chamber A and joined to it by a plurality of bleeder pipes B3 of such size that the air pressure in the chambers A and B2 is substantially the same. This chamber B2 is bounded on its opposed sides by the walls A4 which extend forwardly from the chamber A for that purpose and is bounded at its top by a perforate plate Bill. B4 is the end wall of the device. It forms the end wall for .the chamber B2, projects upwardly thereabove 'to a point above the lower end of the deck BI and supports a Weir or plate B5 mounted for vertical adjustment. B6 is a refuse discharge passage. It extends clear' across the machine between the side walls A4. It is bounded at the rear by lthe wall A2, at the front by the rear wall Bl of the air chamber B2. This channel B6 inclines forwardly as indicated at B8 along the under side of thel chamber B2 and is closed by a pivoted flap gate B9.

C is an air pipe. It communicates at one end with theinterior of the chamber A. It .terminates in a gooseneck CI and has a discharge end C2 passing up through a water or liquid reservoir C3 to terminate above the level C4 of the fluid in Ithe reservoir where it discharges into a' float cup C5, which cup is immersed in the fluid. C6, Cl are adjustable weights mounted on, the float cup C5, and C8., is a link interposed between the cup- C5 and the shaft C9 which carries the pivoted flap gate B9 so that movement of the cup will move the flap gate.

The drive for the butterfly valves is shown in Fig. 5 and comprises opposed pairs of conical driving wheels D DI, D2 D3. A lever D4Ivarics in opposition the distance'between lthe conical wheels of eachpair. D5 is a flexible belt engaged between the opposed faces of these wheels so that as one pair approaches toward and thc belt rides out farther from the center of rotation 2 otherpairrecedesiromoneanothentheilexible from one pair of wheels and closer to the center of rotation of theother pair so that by this method anaccurate control of. the speed of the butterfly valve is obtained.

'Ihe variant speed'drlve has been shown merely as illustrative o! any suitable type o! variable speed drive. It is understood that many diilerent types may be used.

ln the modiiled form of the device shown in Flg.l6,`there is substituted for the fan and butterily valve a Roots type blower 1'I having vanes FI. F2 driven by a motor F8, the speed of which can be controlled inany suitable manner. 'I'he Roots type blower, being a positive displacement pump, insures positive impulses to the air without the interposltion of the butteriiy valve.

Eisabaiiieplateextendingclearacrossthe deck, above the reiuse discharge opening. I t is preferably so positioned that it will be embedded in the refuse and always have above it and between it and the coal a bed oi refuse material.

Intermediate between the air box and the control cup or control means is located the valve G which may be manually set to initially adjust the response ofthe control cup or member and so the response oi the discharge means to the air pressure in the air ilow box. It will be understood of course that when the device is in operation, the control cup constantly pulsates and there is a constant opening and closing, or movement in the direction of opening and/closing. of the refuse valve. This is of course caused by the pulsations or variations in pressure in the air now caused or imparted by the butterily valve or other suitable means. This vibratory or pulsating movement of the refuse gate is of course important in that lt tends to breakup any accumulations of refuse in the discharge chamber.

'I'he high resistance bed is preferably of marbles or shot `o1" some smooth generally spherical objects because. while experience shows that -so far as the control of the air pressure itself is concerned. most any resistance medium will do, the great diiilculty lies in obtaining a resistance medium which will give the desired resistance to air ow and still will be immune from clogging by dust. This is of the' utmost importance be,

cause experience shows that clogging takes place bothasaresultofdustentrainedbytheair Y as it passes upwardly. through the resistance bed andalsoasaresult ofdustpassingdownirom the treating deck into the resistance bed, being there lodged and caught and held when the air ls yturnedoiiandthebedceascstooperiite. The

smooth walled passages are essential to prevent .this clogging. They do not need to be perfectly straight; in fact, they can well be of constantly varying cross section; but they should be smooth walled because, ii' the walls are' rough, dust particles catch, adhere and build up obstructions to theairow. Itisevenbettertohavethem of' varying cross section because, il' the cross section Y should `be constant. there would be too little rewherein the air chamber B2, pipes-B8, periorate platellandthebailleplatelarealldimd with. suheendoftnesecknlinretusechute sacas H. It is hooded at Hi and the refuse sate H2 is pivoted thereon, being controlled in exactly the samemannerandbythesamemechanlsmasthe refuse gate Bl shown in/Fig. 4. The coal or lighter material passes oi! in the same direction, that is. parallel with the axis of the table over the coal chute HI; A weir Hl is ,vertically adjustable to control the coal stream. A plate H5 is vertically 'adjustable to control the refuse stream. Plates HI, Hi are independently adjust;

able and between them and in cooperation with the refuse gate H2 they control the relative proportions of material ilowing to the refuse and coal chutes or through the concentrate and the gangue chutes as the case may be. 'I'he adjust,- ments depend on the size of the material being treated and its particular. peculiar characteristics. In the case ot any particular material. after the proper adjustment has been made. as determined by experiment. it is possible to replace the plates H4 and HI by a single plate which may be welded or riveted in place.

'nils plate intersectin the line of ow of the material on the table is peculiar in that it provides a relatively wide space between the points at which the refusev and the coal are removed. Always when dealing with apparatus such as this and when handling coal as it comes from the mine. the horizontal line of cleavage between the refuse bed and the coal bed as they travel down thedeckisllkelytovary. Inthepast,ithasbeen necessary to very closely position and watch the dividing member to insure that the coal did not come out with the refuse when the refuse bed got-thin. or that refuse did not come out with the coal when the coal bed got thin. My lstructure with this relatively broad plate insures that the refuse is taken from the bottom of the refuse bed and coal taken from the top oi' the coal bed and a very considerable vertical deviation or deiiection of the dividing line between the two beds may take place without interfering with the product.

It will be understood also that the mechanism for causing the pulsation of air and the mechanism for permitting pressure variations and pressure pulsations to the refuse gate all may be varied without departing from the general principles ol' operation o! my device.

The use and operation of my invention are as follows:

With the device set up `as indicated in the drawings, the fanis started forcing air under pressure into the'air chamber. At the same time the butterfly valve rotates. This butterily valve is so arrangedthat even when in the closed position it does not entirely cut ofi.' the flow of air. As it rotates it thus increases and ,decreases periodically the amount of air fed to the air chamber. thus causing.I the pressure in the chamber to vary at a controlled rate of speed. andthe air always ilowsup through the nxed resistance bed, but the pressure available pulsates orvarlesbetweenaminlminnandamaximum. There is never any backward movement of the air in the direction oi the resistance bed. but always an outward movement of the air through the bed and through the deck.

Ooal or other suitable material is then'fed" stream the trough, being pulsated or .vi-

brated vertically as it ilows generally horizontally under the influence of gravity, no vibration of the device itself occurring or being desired. The pulsating air stream sets up a vibration inthe body of flowing material giving it a liquid or fluid characteristic much greater than without the pulsating air now. This liquid characteristic is sumcient to enable the heavier particles as the ow goes on to gravitate to the bottom and the lighter particles to the top. This forms a bed which toward the lower end consists in light mamakes itself felt in the control cup as indicated;

thereby raising it and opening the refuse flap valve wider. It will be understood, of course, that the refuse flap valve is ordinarily set so that it isl always partially open, but this variation in pressure in-the air chamber caused by variation in' the resistance to the escape of the air results in opening or closing the refuse valve moreor less so as to maintain toward the lower end of the chute or trough on the lower end ofthe perforate deck,A

a bed of refuse of the desiredthickness. The coal, which by the time it reaches the lower end of the chute will have become separated from the refuse, will run out over the adjustable Weir or gate at the lower en d while the refuse runs out through the refuse spout.

It win be noted that beyond the refuse` spout isa bank or wall of refuse which takes an upwardly inclined position andis kept alive'by the pulsating effect of the air coming through the i perforate plate Bil and provides a live abutment to bound the lower limit -of the refuse bed. The deector plate extending as-it does horizontally across the refuse discharge opening insures that the refuse runs in from the side and not from the .top and vthus prevents excessive local draining on' of the refuse bed which might result in drawing coal down through the refuse discharge. The only adjustments that are necessary are the height of the weir or discharg gate which assists in controlling the depth of the'coal and refuse bed immediately at the coal discharge, the speed of the butterfly valve which controls the rate of pulsation, the weight of the float cup which controls the degree of opening of the refuse discharge gate, and thefiuid pressure supplied by the fan or pump. Experience shows that under ordinary conditions when these adjustments have i been made, the apparatus will thereafter. unless change in product or change in the material treated is desired, continue substantially without change to operate in a satisfactory manner.

In view of the fact that the deck is smooth and unobstructed, there is no tendency toward the hanging or sticking of material on the deck and the constant upward movement of air through the perforations in the deck prevents clogging, plugging or blinding. It is true that wet or soggy material cannot be as satisfactorily separated on any air 'deck as can 'dry material. but the presence 'of wet or soggy material merely decreases for a time to `il. limited extent the separating effect but does not interfere with the operation of the device beyond that, and moreover,

assoonasthewetrnateriaihaspassedoifthe deck, operation continues without change in any rf it is desired to use a nula medium other than air for separation, water, gases or other 5- liquidsmay be usedI being treated in the same way except that other means may be provided.

than the buttery valve for interrupting the flow, c

or there may be substituted for the .buttery valve and centrifugal fan, a positive displacement pump which will give a pulsating effect. This is shown diagrammatically in Fig. 6.

` Preferably, I propose to use a separating fluid medium which is fed through the bedof material to be classied pulsatingly in a continuous forward moving current. at varying speed which of pre means vthat normally there is always a re in the air chamber, the pressure increasing and decreasing periodically.

1t wm be noted valso that the resistance bede beneath the deck is a fixed immovably held bed, and the material or particles between the under side of the deck and the perforated plateswhich form this resistance bed are held in fixed posi- .tion between the deck and the plates so that they do not move, vibrate or have any displace- -ment in response'to the current of separating or floating medium. They merely serve as a part of a. fixed immovable resistance bed. r

The use of the buttery valve interposed be- 30 tween the fan or pressure source and the resistance bed causes theY pulsatingA current eect, but because the valve never entirely closes the air duct. and since the fan or blower continuously operates, the partial interruption of the current Yby the valve seems to build up excess pressure which is released as the valve is opened. thereby increasing the pulsating effect.

I claim:

l. In `a concentrator, a downwardly inclined pervious unobstructed deck of constant width,A means for feeding a continuous sheet of material by gravity ac'ross said deck, means for forcing a fluid medium upwardly through the deck and the sheet of material thereon, a fixed high resistance bed on the under side of the deck, the resistance of said bed to fluid ow decreasing toward the lower edge thereof, a perforate plate spaced from but in general alignment with the lower Aboundary of the pervious deck and adapted to receive and support material as it travels across the lower boundary of the des?, means for forcing a fluid medium upwardly through such plate, a concentrate chute extending clear across y the deck and interposed between its lower boundary and said perforate plate,` and a baille plate generally parallel with the' direction of ow of material along `the deck and spaced above the deck, said baille plate overlying the said concentrate chute and projecting on its upstream side away from said chute to overlie the resistance bed and on` its downstream side away fromthe chute to overlie said perforate plate. y

2. In a concentrator, a downwardly inclined pervious unobstructed deck of constant width. means for feeding a continuous sheet of material by gravity across said deck, means including an air chamber for forcing air upwardly through said deck and the sheet of material thereon, a fixed high resist-ance bed on the under side 'of the deck and between the same,` andsaid air chamber, the resistance of said bed to air flow decreasing toward the lower edge thereof, a perforate plate spaced lfrom but in general alignment with the lower boimdary of the pervious 75 and adapted to receive and support material velsacrosthelowerboundary of the means for forcing air upwardly through deck and interposed between its lower boxmdary and said perforate plate, and a b aiiie plate generally parallel with the direction of now of material along the deck and spaced. above the deck, said baille plateoverLving'said concentrate chute and projecting on its upstream side away from the chute to overlie the resistance bed and on its d side away from the chute to overlie the perforate plate.

3. In a concentrator, a downwardly inclined perviousdeck, means for feeding a continuous sheet of material by gravity across said deck,

means for forcing a fluid medium 'upwardly' through the deck and the sheet of material thereon. a nxed resistance bed on the under side of the deck. the resistance of which to iiuid ovy decreases toward the loweredge thereof, a weir spaced horizontally from the lower end of said deck and projecting upwardly thereabove over which the tailings may pass, a perforate plate between the weir and the deck, means forfforeing Y through the deck and the bed .terial to travel thereacross the nuid medium upwardly through theplate in' the saine general manner asit is forced through the deck, a refuse discharge chute extending clear across the deck and between it and the perforate plate, and a baille plate overlying the refuse discharge chute generally parallel with the deck vand located at a point below the weil'.V

4. In an Vair concentrator, anairkperviouamaterial supporting deck, means for supplying material to travel thereacross under the inuence of gravity, means for effecting a separation of material, toward the discharge end of the deck, along horizontal planes, said last means including apparatus for forcing a vcontinuous uninterrupted column of air under pressure upwardly of material thereon, and automatic means responsive to variation in the air pressure beneath the deck for varying the relative proportions of separated material in the discharge zones as they leave the deck.

5. In an air concentrator, an air pervious. material supporting deck, means for supplying maunder the influence of gravity, means for effecting a separation of materiaktoward the discharge end of the deck, along horizontal planes, said last means including apparatus for/ forcing a continuous uninterrupted column of air under pressure upwardly through the deck and the bed of material thereon and for imparting a pulsating effect to the air column, and automatic means responsive to variation in the air pressure .beneaththe deck for varying the relative proportions of separated material in the discharge zones as they leave the deck. f

`6. In an air separator, an air chamber, a resistance bed and an inclined separation deck in superimposed relation. means forV delivering mixed material to the separation deck, means for maintaining air pressure in said air chamber. whereby air is forced through said bed and deck to cause new of the material down the deck, said material being separated into different layers toward the lower end of the deck, means for withdrawing a limited quantity of material from the lower layer', and means responsive to the increasedairpresslu'einsaidairchamberdueto 21,7esa

increasing thickness of said lower layer for correspondingly increasing `the amount of material' Withdrawn.

7. In anair separator, an air chamber, a resistance bed and an inclined separation deck in superimposed relation, means` ,for delivering mixed material to the separation deck, means for maintaining air pressure in said air chamber, whereby airis forced through said bed and deck to cause flow of thematerial down the deck, said material being separated into di'erent layers toward the lower end of the deck, means includ ing a 'gate for withdrawing. a limited quantity of material from the layer next to' ,said deck; a Y pneumatic device for controlling said gate,' and an air pipe connecting said device with said air chamber, whereby an increased air pressure in the air chamber due to. excess accumulation of material L-on the deck will cause the said gate to release a greater quantity of material.

8. In an air separator, an inclined deck which is pervious to air but impervious to coal or refuse, means for supplying crude coal to said deck at the upper end thereof, a vresistance bed beneath said deck, an air chamber beneath said resistance bed, means for maintaining air pressure in said chamber and for modulating the pressure to force a pulsating stream of air up through said bed and deck and the coal thereon, whereby said coal is caused to flow down the deck to the lower end thereof, and whereby the refuse separates.

to the deck by air pressure in said chamber, whereby if the' pressure increases duel to excessive thickness of the refuse layer the gate will be opened farther toincrease the rate atV which refuse is discharged down said chute. l

9. In an airy separator, an inclined deck which vis pervious to air but impervious to coal or refuse, means for supplying crude coal to said deck yat the upper end thereof, a resistance bed beneath saidgeck, an air chamber beneath said resistance bed. means for maintaining air pressure in said chamber and for modulating the pressure to force a pulsating stream of airup through said .bed and deck and ythe coal thereon. whereby said coal is caused to now down the deck tothe lower end thereof, and whereby the refuse separates from the coal yand collects reason oi' its greater specific gravity, means for withdrawing refuse from oi! the lower end of the deck, means for limiting the rate at which refuse isso withdrawn to cause the refuse to accumulate on the lower end ofthe deck in a layer sired thickness, means for withdrawing coal from oil' the lower end of the deck .above said refuse layer, and'means responsive to an increase of air/ 10. In an air separator, an inclined separating iloorordeckwhichispervioustoairbutimpervious to thematerial to be treated, side walls of the denext to the deck Aby l cooperating with said deck to form a trough, a

chute for takim oi! material fm u.. 1.... -l

the lower end thereof, a gate for closing said chute below the level of the deck. an air chamber beneath said deck, means for delivering material to the upper end of said deck, means for supplying air under pressure to said air chamber and for intermittently increasing and decreasing the` pressure, whereby'apulsating current of air is forced upward through said deck and the material thereon to'cause said material to ow dowrithe deckand separate into different layers, the lowermost layer being received in said chute,

`and means governed by the air pressure in said chamber to regulate the closing of said gate so as to maintain said chute full of material, said last means being also eil'ective to vibrate the gate in response to the pulsating pressure in the air chamber to prevent clogging of the chute.

il. In 'an air separator, an inclined separating .door or deck which is pervious to air but impervious to the material to be treated, means ,for continuously delivering material to said deck at the upper end thereof. `means for forcing a pulsating current of air upward through the deck and the material thereon to cause said material to` flow across the deck toward the lower end thereof,

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