US2966262A - Method and apparatus for separating ores - Google Patents

Description

Dec. 27, 1960 E. A. HOBART METHOD AND APPARATUS FOR SEPARATING ORES Filed July 11, 1957 5 Sheets-Sheet 1 LI QRKF EDWARD A. HOBART ATTORNEYS Dec. 27, 1960 E. A. HOBART 2,966,262

METHOD AND APPARATUS FOR SEPARATING ORES Filed July 11, 1957 5 Sheets-Sheet 2 FIG-Z INVENTOR.

EDWARD A. HOBART BY W 4,.

ATTO RNE YS Dec. 27, 1960 I E. A. HOBART 2,956,262

METHOD AND APPARATUS FOR SEPARATING ORES Filed July 11, 1957 5 Sheets-Sheet 3 INVENTOR. EDWARD A. HOBART ATTORNEYS Dec. 27, 1960 E. A. HOBART 2,966,262

METHOD AND APPARATUS FOR SEPARA'IING ORES Filed July 11, 1957 5 Sheets-Sheet 4 INVENTOR. EDWARD A. HOBART ATTORNEYS Dec. 27, 1960 E. A. HOBART METHOD AND APPARATUS FOR SEPARATING ORES Filed July 11, 1957 5 Sheets-Sheet 5 EDWARD A. HOBART ATTORNEYS 2,965,262 METHGD AND APFARATUS FOR SEPARATENG ORES Edward A. Hobart, Troy, fihio, assignor to The Hobart Err others Company, Troy, Ghio, a corporation of Ohio Filed July 11, 1957, Ser. No. 671,194 7 Claims. (Cl. 209-13) This invention relates to an ore separating device of the type in which granular materials such as sand are separated by the action of gravity while in the form of a slurry. The present invention is a further extension and improvement of the general method of separating ores of the nature disclosed in my issued Patent 2,780,356 of February 5, 1957, and my co-pending application Serial No. 605,310, filed August 21, 1956.

It has been found that many sand deposits, particularly beach or ocean sands, contain a fairly large percertange of valuable minerals, particularly titanium compounds which are valuable in commerce. Such sands also generally contain zircon and other minerals such as lencopane, rutile, monazite, and various silicates such as sillimanite, kyanite, staurolite, tourmaline and garnet. A characteristic of those minerals which are commercially desirable is that they are heavier than the bulk of the sand making up the mixture. The present invention has been devised to take advantage of this difference in spe cific gravity between the bulk of the sand and the minerals it is desired to recover in order to effect an efficient separation thereof.

In the patent and pending application referred to above a slurry of sand bearing a heavy and valuable mineral component is passed down a sluice that tapers inwardly toward the discharge and whereby the heavy mineral component tends to separate out and is taken off the bottom of the stream of slurry. A repetition of this basic process a number of times serves to concentrate the heavy mineral to a commercial grade, say fifty percent or better heavy mineral.

In the patent and application referred to above, the slurry is passed downwardly through several separating stations and the fractions of the slurry are separately collected and the lightest of these factions is generally immediately discarded and the other fractions are then pumped upwardly and passed through another series of separating or splitting stations. The general mode of operation usually requires the provision of relatively large tanks for receiving and retaining the fractions split off and the provision of pumps for pumping the fractions to the inlets of the separating or splitting stations in which they are further processed.

The present invention has as a primary object the provision of a highly eificient ore separating arrangement in which the provision of large storage tanks is eliminated.

Another object of the present invention is the provision of an ore separating arrangement of the nature referred to in which the material does not have to be pumped repetitively but is only pumped once at the time that the material is initially picked up.

Another object of this invention is the provision of an ore separating arrangement in which multiple fractions of the ore can be obtained in a relatively simple manner.

It is also an object to provide a method of separating ores such that a highly efficient work cycle obtains and which is exceedingly rapid in operation.

A still further object of the invention is the provision of a separating arrangement for granulated ores and the like adapted for attachment to substantially conventional sluices and operating on a different plan from the so called free-flow,separators and in which separators the number of fractions that can be taken is severely limited.

A still further object of the present invention is the provision of a separating or splitting arrangement for removing the heavy component from a sand slurry in which the heavy component once separated from the slurry is prevented from again being entrained in the main stream of the slurry.

A still further object of this invention is the provision of an arrangement for removing the heavy component from a slurry of sand in which the split of? component can be substantially de-aired thereby eliminating foaming thereof and facilitating further handling of the heavy component.

These and other objects and advantages will become more apparent from reference to the drawings in which:

Figure l is a side elevational view partly broken away showing in general the construction of a barge mounted separator according to the present invention;

Figure 2 is a transverse sectional view indicated by line 2-2 on Figure 1 and drawn at a larger scale than Figure 1 showing the compartments of the separating unit of the present invention;

Figure 3 is a side elevational view looking in from the left side of Figure 2;

Figure 4 is a longitudinal sectional view showing somewhat diagrammatically the construction of the pick up boom by means of which a sand-water slurry is picked up and delivered to the separator;

Figure 5 is a plan view looking down on top of one of the sluices through which the slurry flows as it approaches a separating stage;

Figure 6 is a view looking down on top of the separating device that is attached to the end of the sluice;

Figure 7 is a view looking in from the outer end of the separating device;

Figure 8 is a view drawn at enlarged scale showing the action which takes place when a slurry of sand is delivered to a sluice and is separated by the separating device at the end thereof;

Figure 9 is a view drawn at still larger scale showing the action which takes place in the separating device; and

Figure 10 is a view drawn at considerably larger scale showing the action which obtains in one of the compartments of the separating device at the end of the sluice.

Referring to the drawings somewhat more in detail, the arrangement shown in the drawing comprises a barge 1i). Mounted on barge 10 are a plurality of separating stages generally indicated at E2 and to which a sandwater slurry is delivered at the top from troughs 14 extending longitudinally along the barge at an upper portion of the frame work. A sand-water slurry is supplied to troughs 14 from a cylindrical screen 3.6 that is rotatably mounted at its opposite ends as by rollers 18 and which is adapted for being driven in rotation by a central gear 20 arranged for being actuated by a motor 22.

The slurry supplied to the screen 16 is delivered thereto through a conduit 24 which has therein at its lower end a pump 26, for example, of a propeller type, adapted for being driven by a motor 28 carried by the conduit. The propeller type pump is to be preferred because it can be made to handle large stones and the like and without damage and will have long life when running in a sand slurry, especially if the propeller is coated with rubber. The conduit 24 may also be lined with rubber if so desired and which will increase its life.

The slurry picked up by pump 26 is loosened from the bottom of the body of water on which barge 10 floats or from the beach by an agitator element 30 on the end of conduit 24 that is arranged for being driven by a motor 32 via reduction gearing 34.

The conduit 24 which, together with the agitator and pumping arrangement may be referred to as a pick up boom, is pivotally supported on the barge at 36 and is 3. adapted for being adjusted as to the elevation of the outer end by a cable hoist 38.

The end of the barge opposite the pick up boom may be provided with spuds 40 at the opposite corners each being provided with a pick up hoist 42 so that the spuds can both be raised at one time for movement of the barge or can be lowered individually so that the barge will swing back and forth and thus sweep a certain area so that materials can be loosened and picked up there- 7 from.

Reference to Figure 2 will show that the troughs 14 are provided with individual screw conveyors 44 driven by motors 46 so that sand delivered to the troughs is moved lengthwise thereof so that it will drop through the discharge openings 48 into the basins 50 formed at the upper ends of the first bank of inclined sluices 52.

The division of sand between the troughs 14 may be regulated by a tiltable baffle plate 53 so that the troughs receive about the same amounts of sand. This also permits shutting off one side of the separator while keeping the other side in operation if so desired.

The sand delivered to the upper bank of the sluices passes down to the lower end thereof and is separated by the separating devices 54 at the ends of the sluices. The separating devices 54' discharge a lighter fraction that passes out to the outer ends of the separating devices to a catch basin 56 that is connected 'by conduit means 58 with a tailings tank 69 formed in the bottom of the barge. From the tailings tank the material collected therein is discharged either back to the bottom from which it was lifted or it may be delivered to trucks to be taken away for use as fill dirt or the like.

As will be seen in Figure 2 the separating devices 54 deliver heavier fractions to the basins '62 of a second bank of sluices 54 that are inclined at the opposite angles to the sluices 52 and extend inwardly toward the center of the barge. At the inner end of sluices 64 there re the separating devices 66 that deliver a light fraction of the slurry to a catch basin 68 connected by conduit 70 with tailings tank 69, while a heavy fraction of the slurry is delivered to basin 72 of sluices 74 that are inclined the same way as sluices 52and are located therebeneath.

In a similar manner sluices 74 deliver a light fraction to a catch basin 76 and a heavy fraction to sluices 78 which are inclined the same way as sluices 64.

Sluices 73 in turn deliver a light fraction to catch basins 8t and the heavy fraction to sluices 82 which will be seen to be inclined the same as sluices 52. In turn sluices 32 deliver a light fraction to a catch basin 84 and a heavy fraction to a similar sluice 86 which discharges a light fraction to a catch basin 88 communicating with tailings tank 6% and a heavy fraction to a catch basin 90. This heavy fraction is the heavy minerals that are to be recovered and they are conveyed to a refining plant and the valuable minerals contained therein may be re- 7 7 covered.

' the separating action.

It will be understood that water could be added to the slurry at any point if so desired in order, to make it more fluid and while no arrangement has been shown, it will be appreciated that a simple pumping arrangement could be provided for drawing fluid from the body of water in which the barge 10 floats and with thiswater being delivered to whichever ones of the basins of the sluices required additional water to form a freely flowable slurry;

'The construction of the sluices and the separating device'sat the ends thereof and the operation of these elements is more completely illustrated in Figures ,4 through 10. In these figures it will be noted that each sluice comprises a relatively wide inlet end, that consists of basin portion 100. The slurry delivered to the basin portion 100 swirls about therein and becomes completely admixed and flows over the lip 102 into the inclined trough part 104. This trough part tapers down to a relatively narrow discharge end, say, about A" or so, so that the slurry as it is moved down the sluice is caused to form into a relatively deep stream with the heavy portion migrated toward the bottom thereof and the lighter portion toward the top of the stream. The separating however, of the heavy material from the light is augmented by the narrowing of the sluice described so that the bottom layer of the stream is heavy laden with the minerals it is desired to recover.

As will be best seen in Figures 8, 9 and 10 according to this invention there is no free-fall of the slurry but instead this slurry is delivered outwardly into a separating device 106 which has substantially parallel side walls and a plurality of small compartments 108 separated by transversely extending relatively narrow walls 110 which function as skimming blades. At the extreme outer end of the separating device there is a large discharge opening 112 through which the tailings pass.

As the slurry emerges from the end of the sluice and passes through the separating device between the parallel side walls thereof, the lower portion of the slurry is skimmed therefrom by the walls 110 which, as mentioned, serve as skimming blades, so that a small portion of the slurry is caught in each of the compartments 108 while the main portion of the slurry passes outwardly through the discharge 112. By adjusting the angle of the sluices any desired portion of the slurry can be skimmed off the bottom and experiment has shown that an angle in the region of from 15 to 17 is satisfactory for minerals having a normal content of heavy minerals, such as beach sand, but it is to be understood that this particular angle is only exemplary for this material and that it might vary from as little as 10 to 20 or 25.

It will be noted that the separating devices are arranged to fit directly onto the end of the sluices and can be clamped thereon by the clamp means 114 so that the new method and apparatus of separating ores accord ing to the present invention can be adapted to existing separators of the nature utilizing the free-fall or fan method of separating.

It is to be noted, particularly in Figures 9 and 10 that the fraction of the slurry that is picked up in any compartment 108 tends to swirl about and a pocket of air 116 is formed that tends to separate the body of heavy minerals in the compartment from the main stream of the slurry so that the heavy material once delivered to compartment 108 does not tend again to become entrained in the main stream of the material but instead drains downwardly through the discharge ports in the bottom of the separating device. In this manner a highly efficient separating action is obtained. This also tends to separate air from the heavy component so that the slurry draining through the discharge port is substantially air free.

Whileit will'be evident that the particular size of the compartments 108 and the spacing thereof would be subject to wide variation to meet varying conditions, it has been found that a practical and workable structure for use with a sluice having a discharge window of about with the sluice being about 2 /2 to 3 long, has the compartments spaced l'fi apart and with the side walls of the separating device being about /3" apart. Six compartments for receiving heavy minerals have been illustrated, but there might be more or fewer of these compartments in order to meet particular circumstances. Similarly, all of the compartments have been illustrated as delivering a component to the basin of the next sluice beneath the separating device, but it is conceivable that one or more of the compartments might discharge elsewhere to advantage. Since the heaviest portion of minerals is received in the first separating compartment, this compartment might, for example, deliver its component directly to the heavy mineral receiving catch basin and in this manner unload to a degree the remainder of the separating devices. Also, as has been developed in my issued patent referred to above, some of the split-oft fractions might be reflexed through one or more additional splitting stations to remove still more of the light sand therefrom. Such modifications in the construction of the separating devices and the paths taken by the heavy mineral components is thus contemplated with the purview of this invention.

As a specific example of the results obtained by an arrangement of the nature described, a sluice set on an angle of 17 from the horizontal was supplied with a slurry of 50% water and 50% sand at the rate of 2140 pounds per hour, the recoverable heavy mineral fraction in this case amounted to 2.06%. The following table illustrates the conditions existing over a period of time.

In another case, a sluice set at the same angle was supplied with a slurry consisting of 75% water and 75 sand at the rate of 2005 pounds per hour with the recoverable heavy mineral in the head feed amounting to 1.92%.

The following schedule lists the conditions obtaining in connection with this test.

Percent of Percent of Percent of Heavy total Heavy Compartment N 0. Total Sand Heavy Mineral in Mineral Coming Out Mineral in Each Com- Coming of Each Each Compartment Out of Compartpartment ach Comment rartment In still another case with a sluice set at 19 from the horizontal and with a slurry consisting of 60% water and 40% sand being supplied thereto at the rate of 2,000 pounds per hour and with there being a 12% concentrate of heavy mineral in the sand, the following percentages of heavy mineral were separated from the stream by the compartments in the separating device commencing with the compartment nearest the end of the sluice and ending with the discharge opening through which the tailings pass:

Percent of Heavy Mineral in Each Compartment Compartment No.

It will be understood that this invention is susceptible to modification in order to adapt it to different usages and conditions; and, accordingly, it is desired to comprehend such modifications within this invention as may fall within the scope of the appended claims.

I claim:

1. In an ore separator; two separators arranged side by side, each separator comprising a plurality of separating units in side by side relation in a horizontal line, each separating unit comprising a plurality of individual gravity separating stages arranged one above the other in series so that each separating stage will discharge a heavy fraction to the stage therebeneath, means for collecting the heavy fraction from the last stage of each unit and which represents the recoverable mineral, a pair of hoppers extending along above the separating units, an inclined screen located above the hoppers, means for delivering a slurry of sand and water to the upper end of the screen so that the said sand and water will fall through the screen into the hoppers, and means for discharging particles above a predetermined size from the lower end of the screen, each hopper having feed means therein for distributing the sand therealong to promote a uniform supply to the said separating units, and there being baffle means between the screen and the hoppers adjustable for determining the division of sand between the hoppers.

2. In a gravity separating arrangement; an inclined sluice, said sluice comprising a basin at its upper end to which a slurry of sand and water is delivered, said sluice tapering inwardly toward its lower end so that the stream of slurry therein deepens and heavy particles tend to migrate toward the bottom, and means at the end of the sluice for removing the said heavy particles from the stream, said means comprising substantially parallel side walls, said means also having a bottom portion with an upper surface forming substantially a continuation of the bottom wall of the sluice, said upper surface of said portion bottom being provided with a plurality of transversely extending openings forming upwardly opening compartments and there being a discharge opening leading from said means at the end farthest from the end of the sluice, and each said compartment having an outlet loading from the bottom thereof out through the said bottom portion of said means whereby a heavy fraction of the stream is skimmed 011 the bottom thereof into each said compartment to be delivered from the compartment through the outlet in the bottom thereof to a point of recovery or to another separating station.

3. In combination with an inclined sluice tapering inwardly toward its lower end, a device fixed to the lower end of the sluice, and comprising parallel side walls forming substantially a continuation of the side Walls of the sluice, said device having a bottom wall forming substantially a continuation of the bottom wall of the sluice, said bottom wall being formed with a plurality of transversely extending compartments separated by relatively narrow walls and there being a discharge from the device at the end opposite the sluice, each said compartment receiving a heavy fraction from the stream of slurry passing from the sluice into the device, and each said compartment having an outlet in its bottom for delivery of the fraction to a point of recovery or to another separating device.

4. In combination with an inclined sluice tapering inwardly toward its lower end, a device fixed to the lower end of the sluice, and comprising parallel side walls forming substantially a continuation of the side walls of the sluice, said device having a bottom wall forming substantially a continuation of the bottom wall of the sluice, said bottom wall being formed with a plurality of transversely extending compartments separated by relatively narrow walls and there being a discharge from the device at the end opposite the sluice, each said compartment receiving a heavy fraction from the stream of slurry passing from the sluice into the device, and each said compartment having an outlet in its bottom for delivery of the fraction to a point of recovery or to another separating device, each said compartment having a rounded bottom so that the fraction delivered thereto tends to move in a circular pocket toward the top of the compartment and beneath the main stream of the slurry passing through the device thereby preventing the heavy fraction that enters the compartment from again becoming entrained in the main stream of the slurry.

5. In combination; an inclined sluice adapted for receiving a slurry of sand and water, said sluice tapering inwardly toward its lower end so that the stream therein forms into a relatively deep stream with the heavy particles migrating toward the bottom of the stream, and a device adapted for detachable connection to the lower end of the sluice, said device having parallel side walls between which the end of the sluice closely fits and having a bottom wall forming substantially a continuation of the bottom Wall of the sluice, said bottom wall being formed with a plurality of laterally extending compartments separated by relatively thin laterally extending walls and said device also having a tailings discharge at the end opposite its connection with the sluice, each compartment having a discharge opening in the bottom.

6. In combination; an inclined sluice adapted for re-.

ceiving a slurry of sand and water, said sluice tapering inwardly toward its lower end so that the stream therein forms into a relatively deep stream with the heavy p'a-r ticles migrating toward the bottom of the stream, and a device adapted for detachable connection to the lower end of the sluice, said device having parallel sidewalls between which the end of the sluice closely fits and having bottom walls forming substantially a continuation of the bottom wall of the sluice, said bottom wall being formed with a plurality of laterally extending compartments separated by relatively thin laterally extending walls and said device also having a tailirigs discharge at th'e'end opposite its connection with the sluice, each'co'm partment having a discharge opening in the bottom, each compartment having rounded bottom surfaces so that the fraction delivered thereto tends to niove in a rotary path whereby an air pocket is formed in the top of each compartment preventing the fraction in theco'mpartrn'ent from again entering the main stream of the sluice.

7. In a separating apparatus for separating a heavy mineral component from a slurry of sand and water, an inclined sluice tapering inwardly toward its lower discharge end, and means for skimming off a heavy fraction from the bottom of the stream as it emerges from the sluice but without the stream going into a condition of free-fall, 'said means comprising parallel walls forming extensions of the side walls of the sluice, a plurality of transversely extending narrow Walls forming skimming blades extending between said walls and spaced at intervals from the end or the sluice and being coplanar with the bottom wall of the sluice, and there being a discharge for the slurry which is not skimmed off from said stream at the end of said means remote from the sluice.

References Cited in the file of this patent UNITED STATES PATENTS 557,178 Wood et al Mar. 31, 1896 1,065,563 Thibault June 24, 1913 1,696,767 Hoyois ..n B60525, 1928 1,8'l1,408 Stebbins June 23, 1931 2,204,584 Flower -2 June 18, 1940 2,265,570 Nicol Dec. 9, 1941 2,293,228 Tucker Aug. 18, 1942 2,766,882 Cannon et al. "Oc't. 1'6, 1956 2,780,356 Hobart Feb 5 19 7 2,872,041 Fontein et al. Feb. 3, 1959

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