US3065919A - Ore concentrator - Google Patents

Description

A. LE ROY BURKETT ETAL 3,065,919

Nov. 27, 1962 ORE CONCENTRATOR 3 Sheets-Sheet 2 Filed Sept. 6, 1960 INVENTORS NOW 1962 A. LE ROY BURKETT ETAL 3,065,919

ORE CONCENTRATOR Filed Sept. 6. 1960 3 Sheets-Sheet 3 INVENTORS fliimrliiarhP/rzrr 5/005 7: E T

' v %EY United States Patent ice 3,065,919 ORE CONCENTRATOR Albert Le Roy Burkett, and Andrew T. Sweet, Denver, Colo., assignors, by direct and mesne assignments, to Colorado Manufacturing & Mining (30., Inn, Denver, Colo., a corporation of Colorado Filed Sept. 6, 1%8, Ser. No. 53,958 3 Claims. (ill. 241-161) This invention relates to a machine for comminuting consolidated sedimentary rocks andrecovering the mineral values therefrom.

Natural sedimentary rocks comprise sand grains cemented or attached together by various alluvial materials toform solid rock masses. In certain localities, it has been found that mineral values such as uranium, copper, zinc, molybdenum, etc., have been entrapped between or deposited upon the individual sand grains. Heretofore, it has been customary to crush these con glomerate masses or pieces -to substantially grain size and to then subject the grains to a final grinding or powdering step to liberate the mineral values so that a hydraulic separation could be made between the intersticial, mineral-carrying coating material and the pulverized sand grains. This final fine grinding produces a large volume of valueless sludge material and so increases the milling costs that it is profitable to mill only the exceedingly high grade ores having a high percentage of mineral values although vast amounts of mineral values are present in the ores of lower grade.

The principal object of this invention is to provide a method and means which will make the expensive fine grinding of the rock grains completely unnecessary and which will reduce the conglomerate material to grain size without crushing the grains and which will recover the value-carrying intersticial cementing material from the grains so as to proportionately reduce milling cost to enable the lower grade ores to be worked and to enable a higher profit to be made from the higher grade ores.

Another object is to provide means for scouring the grains to remove all value-carrying material from the surfaces thereof and thence separating the material re- .moved from the grains from the grains themselves thereby eliminating the m'ost costly of all milling operations, that is, the exceedingly fine grinding.

A further object of the invention is to provide a dry i ore concentrating device which will disintegrate the consolidated sediments to grain size and simultaneously .abrade and polish the surfaces of the grains to remove the intersticial cementing material in which the values are contained, in the form of a dust which can be collected in any suitable recovery device to produce a valuable dry concentrate of the mineral values.

A still further object of the invention is to provide,

, in a machine designed to break down consolidated sediments and abracle and scour the resulting grains, means tion.

In the drawings: FIG. 1 is a side elevational View of the improved ore comminuting and concentrating machine partially broken away to show the interior elements;

FIGS. 2 and 3 are horizontal cross sectional views lookdownwardly on the lines 22 and 3--3, respectively,

FIG. 4 is a detail fragmentary enlarged section of a portion of the sectional area of FIG. 1 illustrating the type of sand pockets as employed in the machine; and

FIG. 5 is a vertical medial cross section taken on the line 55, FIG. 2.

Briefly, the machine comprises a plurality of rapidly rotating, superimposed, axially-aligned, relatively fiat, annular discs which receive the conglomerate rock particles and throw them centrifugally and tangentially outward against an enclosing wall with an impact sufiicient to comminute the particles into grains and to abrade, scour and polish the surfaces of the resulting grains to produce a valuable dust concentrate which is constantly and permanently removed.

As illustrated, the machine comprises a vertical shaft 10 rotatably supported in a lower thrust bearing 11 and an upper guide bearing 12. The lower thrust bearing 11 is supported upon radial beams 13 extending to and supported by four vertical supporting columns 14. The upper guide bearing 12 is maintained in vertical alignment with the bearing 11 by means of radial supporting arms 15 extending from and supported by the columns 14. The shaft 10 is rotated through the medium of the transmission belts 16 extending from a drive sheave 17 on a shaft drive motor 18, mounted on one of the columns 14, to a driven sheave 19 mounted on the shaft 10 adjacent its lower extremity.

A feed distributing disc 20 is mounted on the shaft 10 above the guide bearing 12 and a plurality of annular throwing discs 21 are mounted on the shaft 10 in vertically spaced relation between the bearings 11 and 12. Each throwing disc 21 is supported on a plurality of radial spokes 22 extending from a hub 23 fixed upon the shaft 10. The annular shape of the discs outlines a circular axial air passage 24 through each disc which is surrounded by an annular upstanding guard flange 25.

The throwing discs are enclosed in a vertical cylindrical barrel 26 which is supported by means of lower spokes 27 and a lower hub 23 from a thrust bearing 28 so as to be rotatable about but axially immovable on the shaft 10. The upper extremity of the barrel 26 is maintained in concentric relation with the shaft by an upper guide bearing 29 from which radial spokes 30 extend to the periphery of the barrel. Thus, it can be seen that the barrel 26 may rotate independently of the shaft 19.

The barrel contains a plurality of cast liner rings 31 superimposed upon each other in stacked relation, therebeing one liner ring substantially in the plane of each throwing disc 21. Each liner ring is provided with an internal annular sand pocket 32. An annular, conicallyinclined funnel plate 33 extends inwardly and downwardly from the sand pocket 32 in each of the liner rings 31 to a position over the axial portion of the next lowermost throwing disc 21, as shown in FIG. 1.

The barrel 26 is rotated independently of the shaft 10 in any desired manner. As illustrated, it is rotated through the medium of a friction drive wheel 34, preferably rubber-tired, mounted on one of the columns 14 in contact with the exterior of the drum and driven from a second drive motor 35 through the medium of a second transmission belt drive 36. Additional-lateral support for the barrel is provided by means of idler wheels 37 mounted on vertical shafts 38 in bearings 39 on the columns 14.

An annular feed ring 40 having an inwardly and down Patented Nov. 27 1 962 apes.

wardly depending annular apron 41 is supported over the barrel 26 in any desired manner, such as by being fixedly mounted upon the arms 15 of the upper guide bearing 12, as indicated at 42. The feed hopper 40 is preferably closed by means of a cap plate 43 through which a concentrically-positioned ore feed chute 44 enters. An annular conical bottom plate 45 is positioned in the bottom of the barrel 26. The bottom plate 45 has a central, flanged, air passage 46 and is preferably supported on the lower spokes 27 so as to direct material toward an annular discharge passage 47 about the periphery of the lower extremity of the barrel 26.

An annular ore receiving trough 48 is supported below the barrel 26 in any suitable manner such as by means of cross braces 49 extending to the columns 14. The top of the annular trough 48 is open so as to receive material falling through the annular discharge passage 47 from the barrel. The bottom of the receiving trough 48 is contoured to form a plurality of hoppers 50, each of which directs material into a vertical discharge conduit 51. The discharge conduits 51 discharge through a top plate 52 on a collection chamber 53 supported from the columns 14 by means of suitable bracing 54. The chamber 53 directs material to a tailings discharge collar 55 through which the tailings are discharged from the machine.

A circular, cup-shaped, open-topped air suction chamber 56 is positioned within the confines of the annular trough 48, from which an air suction conduit 57 leads to the intake of any suitable conventional suction fan or blower by means of which air is constantly drawn downwardly through the feed chute 44, the feed ring 40, the air passages 24 in the discs 21, and the discharge passage 47 in the bottom plate 45. It is conceivable that blower blades could be mounted on the shaft within the circular chamber 56 to draw air downwardly about the shaft 10 and discharge it through the conduit 57 if desired.

The motors, the sheaves and the belt transmission devices are so proportioned that the shaft 10 is rotated at from 500 to 800 rpm. while the barrel 26 is rotated at from 38 to 50 r.p.m. They may be both rotated in the same direction. It is preferred, however, to rotate the barrel in a direction opposite to that of the shaft.

Let us assume that crushed conglomerate, mineral bearing ore is being fed into the feed chute 44 onto the feed disc 20. The rotation of the latter disc will throw the ore particles forcibly against the inner surface of the feed ring 40 with a resulting fractionation of the particles. The fractioned particles will then be directed inwardly and downwardly by the annular ring apron 41, against the guard flange 25 of the uppermost throwing disc 21.

The rapid rotation of the latter throwing disc will instantly impart centrifugal force to the particles so as to throw them tangentially outward with great force into the sand pocket 32 of the uppermost liner ring 31 resulting in additional fractionation. The further fractionated particles will now roll inward down the incline of the uppermost funnel plate 33 to the inner periphery of the second throwing plate where a third fractionation will take place as above described.

The particles continue to cascade downwardly from throwing plate to throwing plate at each of which the above fractionation will be repeated. The particles will finally fall from the sand pocket of the lowermost liner ring and will be guided by the conical bottom plate 45 into the trough 48 and from thence through the conduits 51, the collection chamber 53 to the tailings discharge 55.

The successive impacts against the liner rings and the constant and violent rolling and throwing will scour the rock grains of the adhering, value-containing, cementitious material and create a dust thereof. This valuable dust will be constantly removed by the downwardly flowing air stream and the dust laden air will be treated in conventional cyclones, filters, etc., for the removal of the solid concentrate. The rock grains will be discarded at the tailings discharge.

The liner rings are subjected to a continuous and violent sand blast which would normally rapidly wear the rings away. However, in this device, each of the metallic rings is constantly protected by an annular sand cushion as indicated at 58 in FIG. 4. These annular sand cushions are maintained in place in the sand pockets 32 by the centrifugal force created by the rotating barrel. The sand forming the cushions is constantly changing due to the continuous impact of the incoming sand but always a sufficient amount is present to reduce abrasion.

The machine has an exceedingly large capacity, for instance, with throwing plates 5'0" in diameter rotating at 600 rpm. with a peripheral speed of 9400 f.p.m. the machine will efliciently treat and concentrate from 5 to 6 tons of ore per minute.

While a specific form of the improvement has been described and illustrated herein, it is to be understood that the same may be varied within the scope of the appended claims, without departing from the spirit of the invention.

Having thus described the invention what is claimed and desired secured by Letters Patent is:

1. An ore concentrator comprising: a rotatable, vertical shaft; means for rotating said shaft; a vertical, cylindrical barrel enclosure concentrically surrounding and radially spaced from said shaft and journalled thereon; a plurality of annular throwing discs mounted on said shaft in vertically-spaced relation, said discs having medially positioned openings; means for feeding ore onto the uppermost disc to be thrown tangentially outward against the interior of said barrel enclosure; a feed distributing disc mounted on said shaft overlying and spaced axially from the uppermost throwing disc, said distributing disc covering the openings in the uppermost throwing disc and preventing entrance of ore therein; annular funnel plates supported from said enclosure intermediate said discs for successively returning material from said barrel enclosure to the next lowermost disc; an annular conical bottom plate mounted on said shaft below the lowermost disc and directing material falling from the latter disc radially outward to a circumferential discharge; an annular receiving trough positioned below said circumferential discharge; discharge conduits discharging material from said trough; a circular air chamber positioned below said conical bottom plate and within the confines of said annular receiving trough, said air chamber opening upwardly through the medial openings in said discs; and means for drawing air from said air chamber.

2. An ore concentrator as defined in claim 1 and having means to mount said barrel enclosure freely on said shaft, and means to rotate said enclosure in a direction opposite to said shaft.

3. An ore concentrator comprising: a rotatable vertical shaft; means for rotating said shaft; a plurality of circular, throwing discs mounted on said shaft in vertically-spaced relation said discs having air passages adjacent the axes; a feed distributing disc mounted on said shaft overlying and spaced axially from the uppermost throwing disc, said distributing disc covering the openings in the uppermost throwing disc and preventing entrance of ore therein; a vertical cylindrical barrel concentrically surrounding said shaft and rotatably mounted thereon; a plurality of super-imposed annular liner rings fitted into said barrel, there being one liner ring for each disc; means for feeding ore onto said discs to be thrown tangentially outward against their respective liner rings; upper and lower spoked members in said barrel, said spoked members being mounted on said shaft so as to be rotatable relative thereto; a thrust bearing means supporting said spoked members on said shaft and main- 5 6 taining the liner rings in the planes of their respective the openings in said discs; means for drawing air from discs; a conical bottom plate in the bottom of said said suction chamber; and means for rotating said barrel barrel and directing ore outwardly to circumferential independently of said shaft.

discharge, said bottom plate having an air passage its axis communicating with the air passages in said discs; 5 References Cited ill the file of this P an annular stationary receiving trough positioned below UNITED STATES PATENTS said circumferential discharge and a suction chamber positioned within the confines of said trough below and 2 5 322 223 igg in close relation to said bottom plate to draw an down- 981,489 Hannum p 25, W61

wardly through the openings in said bottom plate and 10

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