US2086584A - Apparatus for separating and cleaning materials - Google Patents

Description

- July 13, 1937. E. sump 2,086,584

APPARATUS FOR SEPARATING AND CLEANING MATERIALS Filed July 29, l952 3 Sheets-Sheet 1 one 000000 In were zar Maya/216341 July 13 1937. E. S UMP 2,086,584

APPARATUS FOR SEPARATING AND CLEANING MATERIALS Filed July 29, 1932 3 sheetsf shee'b 2 /Z4 A A74 E. STUMP 2,086,584

APPARATUS FOR SEPARATING AND CLEANING MATERIALS July 13, 1937.

Filed July 29, 1932 3 Sheets-Sheet 3 In vefi' for r! ,6?

?atented July 13, 1937 STATES RElSSllED PAT APPARATUS FOR SEPARATKNG AND CLEAN- IING MZSTERIQLS Earl Stump, Chicago,

lilL, assignor to Roberts and Schaefcr Company, Chicago, 1111., a corporation of llllinois Application July 29,

Claims.

My invention relates primarily to apparatus for gravitally separating particles of different specific gravities and while it is especially applicable to the cleaning of coal by air, it is useful in con- 5 nection with separating other materials both by the use of air and other fluid separating mediums.

One object of my invention is to provide a machine which can be applied to the separation of fragmentary materials in one operation through a relatively Wide range of sizing, thereby dispensing with the necessity of excessive preliminary screening.

Another object is to provide a material separating device which, will be simple, light, inexpensive, of large capacity, take up a minimum of room and 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 and claims.

My invention is illustrated more or less diagrammatically in the accompanying drawings, wherein-'- Figure 1 is a side elevation;

Figure 2is a plan view;

ure 2;

Figure 4 isa section along the Figure 2;

Figure-5 is a detail of the butterfly valve drive;

Figure 6 is a diagrammatic view of a variant form of blower or pump.

Figure '7 is a modified form of the device.

throughout the several figures. A is an air chamber. It has a bottom A end walls A A side walls A. It is bounded at the top by a perforate wall A A 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 A". The fan is driven by a motor A in the usual manner. A is a butterfly valve interposed in the duct A between the fan and the chamber. A is a power transmission interposed between the motor and the butterfly valve 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 A'? which project upwardly above the chamber is a fixed resistance bed B,

Figure 3 is a section along the line 3-3 of Fig line 4-4 of Like parts are indicated by like characters 1932, Serial No. 625,767

formed preferably of screened gravel, shot sawdust, mineral wool or any suitable material. This resistance bed is bounded at its upper side by a perforate screen or deck B The deck B is inclined to" the wall A so that the thickness of the air'resistance bed or filter decrease from one end to the other. The perforate plates B and A are fixed in position and so related with the resistance bed that the material therein remains at rest and furnishes at all times a fixed unchanging internal resistance bed to control therate at which air escapes from the chamber A and so to control the pressure of air available along the deck surface B The walls A project above the deck surface B to form a trough bounded on its under side by the perforate plate B which plate is as indicated downwardly inclined. B is an auxiliary air chamber located beyond the chamber A and joined to it by a plurality of bleeder pipes B of such size that the air pressure in the chambers A and B is substantially the same. This chamber B is bounded on its opposed sides by the Walls A which extend forwardly from the chamber A for that purpose and is bounded at its top by a perforate plate Blfl. B is the end Wall of the device. It forms the end wall for the chamber B projects upwardly thereabove to a point above the lower end of the deck B and terminates in a weir or plate B mounted for vertical adjustment. B is a tailings discharge passage. It extends clear across the machine between the side walls A. It is bounded at the rear by the wall A at the front by the rear wall 13'' of the air chamber B This channel B inclines forwardly as indicated at B along the under side of the chamber 13 and is closed by a pivoted flap gate B C is an air pipe. It communicates to one end with the interior of the chamber A. It terminates in a goose-neck C and. has a discharge end C passing up through a water or liquid reservoir C to terminate above the lever C of the fluid in the reservoir where it discharges into a float cup C which cup is immersed in the fluid. C C are adjustable weights mounted on the float cup C and C is a lever arm interposed between the cup C and the shaft C which carries the pivoted flap gate B so that movement of the cup will move the flap gate.

The drive for the butterfly valve shown in Figure 5 comprises opposed pairs of conical driving wheels D D D D. A lever D varies in opposition to the distance between the conical wheels of each pair. D is a flexible belt engaged between the opposed faces of these wheels so that as one pair approach toward and the other pair recede from one another, the flexible belt rides out further from the center of rotation from one pair of wheels and closer to the center of rotation of the other pair so that by this method an accurate control of the speed of the butterfly valve is obtained.

E is a baffle plate extending clear across the deck, above the refuse discharge opening. It 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 of refuse material.

In the modified form of the device, there 'is substituted for the fan and butterfly valve a Roots type blower F having vanes F F driven by a motor F the speed of which can be controlled in any suitable manner. The Roots type blower being a positive displacement pump insures positive impulses to the air without the interposition of the butterfly valve and such a device as this can under some circumstances be used to displace a liquid rather than a gaseous fluid so that if water or other similar liquid is used, the same pulsating effect may be obtained.

The variant speed drive has been shown merely as illustrative of any suitable type of variable speed drive. It is understood that many different types may be used.

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 of the control cup or member and so the response of the discharge means to the air pressure in the air flow box. It will be under-- stood of course that when the device is in operation, the control cup constantly pulsates and there is, a constant opening and closing or movementiri the direction of opening and closing of the refuse valve. This is of course caused by the pulsations of variations in pressure in theair flow caused or imparted by the butterfly valve or other suitable means. This vibratory or pulsating movement of the refuse gate is of course important in that it tends to break up any accumulations of refuse in the discharge chamber.

The high resistance bed is preferably of marbles or shot or 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 difficulty lies in obtaining a resistance medium which will give the desired resistance to air flow and still will be immune from clogging by dust. This is of the utmost importance because experience shows that this clo ing takes place both as a result of dust entrained by the air as it passes upwardly through the resistance bed and also as a result of dust passing down from the treating deck into the resistance bed, being there lodged and caught and held when the air is turned off and the bed ceases to operate.

The smooth walled passages are'essential to prevent this clogging. They do not need to be perfectly straight, they can well be of constantly varying cross section because if the walls are rough, dust particles catch, adhere and build up and it is preferably better to have them of varying cross section because if the cross section should be constant, there would be too little resistance to air flow and not enough eddy currents in the bed itself and also there would be a greater chance of refuse bridging or clogging in such minute passages.

' Figure '7 shows a modified form of the device wherein the air chamber B pipes B perforate plate B the refuse passage B the baffle plate E are all dispensed with. At the end of the deck B is a refuse chute H. the refuse gate H is pivoted thereon, being controlled in exactly the same manner and by the same mechanism as the refuse gate C shown in Figure 6. The coal or lighter material passes off in the same direction, that is, parallel with the axis of the table over the coal chute H A weir H is adjustable horizontally to control the coal stream. A plate H is adjustable horizontally to control the refuse stream. Plates H H are independently adjustable and between them and in cooperation with the refuse gate H they control the relative proportions of material flowing to the refuse and coal chutes or through the concentrate and the gangue chutes as the case may be. The important thing is that the adjustment of the gates H H may be experimental adjustments only, that is to say, they depend on the size of the material being treated and its particular, peculiar characteristics.v The adjustment once made when the plant is built, never again needs to be made. So it is possible that when the adjustment has been made, to take it off and put a single plate instead of the two adjustable plates H H which plate will be welded or riveted in place.

It is hooded at H and This plate intersecting the line of flow of the i 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 the deck is likely to vary. In the past, it has been necessary to very closely position and watch the dividing member to insure that'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 structure with this relatively broad plate insures that the refuse is taken from the bottom of-the refuse bed and coal taken from the top of the coal bed and a very considerable vertical deviation or de-- flection 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 supplying air to the flow box, 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 of operation of my device. The use and operation of my invention are as follows: I

With the device .set up as indicated in the drawings, the fan is started forcing air under pressure into the air chamber. At the same time the butterfly valve rotates. This butterfly valve is so arranged that even when in the closed position it does not entirely out off the flow of air. As it rotates it thus increases and decreases any alternation periodically the amount of air fed to the air chamber, thus causing the pressure in the chamber to vary at a con-' trolled rate of speed and the air always flows up through the fixed resistance bed but the pressure available pulsates or varies between a minimum and a maximum. There is never any backward movement of the air in the direction of the resistance'bed but always outward 2,080,584 3 moverLent of the air thr ugh the bed and through or pipes B to pass into the refuse bed which the deck. is below or beyond the refuse spout, to the right Coal or other suitable material is then fed through the spout as indicated onto the upper end of the deck, that is to say, into the trough formed between the perforate deck and the side walls. This material flows down in a continuous stream through the trough being pulsating or vibrating vertically as it flows generally horiof the float cup which-controls the degree of zontally under the influence of gravity, no vi-. bration of the device itself occurring or being desired. The pulsating air stream sets up -a vibration in the body of flowing material giving it a liquid or fluid characteristic much greater than without the pulsating air flow. This liquid characteristic being sufllcient to enable the heavier particles as the flow 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 material or coal at the top supported on heavier material, refuse, slate or the like at the bottom as indicated in Figure 4 of the drawings. This refuse fills up the refuse discharge passage and builds up a bed of refuse at the bottom of the machine beneath the flowing stream of coal. As this bed builds up it adds it, together with the coal and the flowing material on the deck resistance to the escape of air and causes an increase in air-pressure in the air chamber. This increase in air pressure makes itself felt through the air deck in the control oup'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 setso that it is 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 more or less so as to maintain toward the lower end of the chute or trough on the lower end of the perforate deck, a bed of refuse of the desired thickness, the coal which by the tim e 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 end while the refuse runs put through the refuse spout. 4

It will'be noted that beyond the refuse spout is a bank or wall of refuse whiclr takes an upwardly inclined the pulsating effect of the air and'provides a live abutment to bound the lower limit of the refusebed. The deflector 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 thus prevents excessive local draining off of the refuse bed which might result in drawing coal down through the refuse discharge. The only adjustmentsthat are necessary are the height of the weir or discharge gate which assists in' controlling the depth of the refuse bed immediately at the coal discharge, the speed of the butterfly valve which controls the rate of pulsation, andthe weight opening of the refuse discharge gate and the fluid pressure supplied by the fan or pump. Ex-

perience shows that under ordinary conditions when these adjustments have been made, the apparatus will thereafter unless change in product or change in the material treated is deslred, continue substantially without change to operate in a satisfactory manner. The perforated plate B permits air pressure from the chamber 1?, which has reached it through the bleeder pipe position and. is kept alive by as shown in Figure 4.

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 alimited extent the separating effect but does not interfere with the operation of the device beyond that and moreover as soon as the wet material has passed off the deck, operation continues without change in any essential respect.

If it is desired to usea fluid medium other than air for separation, water, gases or other liquids may be used, being treated in the same way exceptthat other means may be provided than the butterfly valve for interrupting the flow or there may be substituted for the butterfly valve and centrifugal fan, a positive displacement pump which will give a pulsating effect. This is shown diagrammatically in Figure 6.

Preferably, I propose to use a separating fluid medium which is fed through the bed of material to be classified pulsatingly in a continuous forward moving current at varying speed which oi course means that normally there is always a pressure in the air chamber, the pressure in- .creasing and decreasing periodically. Under some circumstances, however, it may be desirable to use an alternating current, that is, the air or other fluid medium may' go out and the pressure may drop in .the air chamber or fluid containing box below atmospherlc and exert' a back suction.

It will be noted also that the resistance bed beneath the deck is a fixed and the material or particles between the under side of the deck and the perforated plates which form this resistance bed are about the deck and the plate held in fixed position so that they do not move, vibrate or have any displacement in response to the current of separating or floating medium. They merely serve as a part of a fixed immovable resistance bed.

.The use of the butterfly valve interposed between the fan or pressure source and the resistance bed because the valve never entirely closes the aperture, causes this pulsating or current eifect brft since the pump or fan or blower continuously operates the partial interruption of the current by the butterfly valve seems to tend to build up excess pressure which as the valve is opened is released thereby increasing the pulsating efi'ect.

I claim:

1. In a concentrator, a downwardly inclined pervious unobstructed deck of constant width, means for feeding a continuous sheet of material by gravity there'across, means for forcing a fluid medium upwardly through the deck and the immovably held bed sheet of material thereon, the resistance of which v fluid medium upwardly through such plate, and

aconcentrate chute extending clear across the pervious unobstructed deckof constant width,

means for feeding a continuous sheet of material by gravity thereacross, means for forcing a fluid medium upwardly through the deck and the sheet of material thereon, a fixed high resistancebed on the underside of the deck, the resistance of which to fluid fiow decreases toward the lower. edge thereof, and a perforate plate spaced from but in general alignment with the lower boundary of the pervious deck and adapted to receive and. support material as it travels across the lower boundary of the deck and means for forcing a fluid medium upwardly through such plate, said means comprising an air pocket bounded by said plate and an unobstructed air passage between it and the air chamber, and a concentrate chute extending clear across the deck and interposed between its lower boundary and the' perforate perviousi deck, means for feeding a plate, a battle plate generally parallel with the direction of flow of material along the deck, spaced above the deck, overlying the refuse. chute andprojecting on its upstream 'side away from.

the chute to overlie the resistance bed and on its downstream side away from the chute to overlie the perforated plat e.

3. In a concentrator, a

ntinuous sheet of material by gravity thereac oss, means for forcing ailuid medium upwardly through the deck and the sheet of material thereon, a fixed resistance bed on the underside of the deck, the

resistance of which to fluid flow decreases toward deck.

downwardly inclined the loweredge thereof, a weir extending entirely? aross the deck at the lower end thereof and projecting upwardly thereabove over which the tailclear across the deck and between it and the perforate plate, and a baflle plate overlying the refuse discharge chute generally parallel with the deck and located at a point below the weir. 4. In an air concentrator, an air pervious, material supporting deck, means for supplying ma-' terial to travel thereacross under the influence of gravity, means for effecting a separation of material, toward the discharge end of the deck, along horizontal planes, means for forcing a continuous uninterrupted column of air under pressure upwardly through the deck and the bed of materlal'thereon, 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 5.'In an air concentrator, an air pervious, material supporting deck, means for supplying ma-' terial to travel thereacross under the influence 0f gravity, means for efiecting a separation of material, toward the discharge end of the deck, along horizontal planes, means for forcing a continuous uninterrupted column oi" air under pressure upwardly through the deck and the bed of material thereon and for imparting a pulsating effect to the air column, 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, l

' 9 EARL STUMP.

Images