US1956296A - Apparatus for ore concentration - Google Patents

Description

April 24, 1934. R. B. MARTIN v APPARATUS FOR ORE CONCENTRATION Filed Aug. 5, 1950 2 Sheets-Sheet l April 24, 1934. R. B. MARTIN 1,956,296

APPARATUS FOR ORE CONCENTRATION Filed Aug. 5, 1950 2 Sheets-Sheet 2 INVEN+0 Rhetherfwd B-Nartm BYWM ATTORNEYS Patented Apr. 24, 1934 APPARATUS FOR ORE'CONCENTRATION Rhetherford B. Martin, Roselle, N. J., assignor, by mesne assignments, to Tennessee Corporation Application August 5, 1930, Serial No. 473,184

19 Claims.

concentration of ores, and more particularly tov improving apparatus for concentration by water gravity table methods.

Heretofore the separation of one mineral from another by gravity tables usually has been ef fected by the design andthe angle of the rifiies relative to the tilt of the table and'the impact of the head motion. Insome cases, arrangements in which the deck is in two or more planes joined by sloping surfaces have been employed. In prior practice, the operation has been carried outwith finely crushed ores in a freely flowing pulp. Disadvantages have been encountered, particularly in the small capacity a given table will handle.

One of the principal objects of this invention is to produce a greater concentrating capacity with gravity tables than heretofore accomplished.

Another object of this invention is to concentrate by gravity tables a coarser feed than heretofore employed.

Yet another object of this invention is to give a greater mobility to the mineral and gangue particles in the flowingpulpl' undergoing concentration and thereby improve the stratifying action of the table with improvement in the grade of concentrate while at the same time increasing the capacity of the table.

A further object of this invention'is to discharge from gravity tables the separated constituents of ores at a greater speed than heretofore possible.

In practicing my invention I utilize the well known gravity concentrating tables such as the Wilfiey, the Deister, the James and the like, which had been in common use for gravity separation of ores. I so modify the construction thereof as to render the action of said tables vastly more efficient than heretofore. I place upon the tableswires, or the equivalent, so as to facilitate the action of the table' and the separation of the ore, from the gangue. These wires are generally placed at an angle to the riffles and-usually I provide one or more sets of parallel wires placed apart a' sufiicient and satisfactory distance. l

I have found that by covering the riflles of concentrating tables with metal strips, or more particularly, wires spaced 1% inches apart, the volume of feed may be increased ten to twenty times that a normal table would handle. It is important that the wires shall be inclined at an angle to the rifiles such that the movement lengthwise of the table of the solid particles (ore and/ or sand) in the portions of the body of pulp on the table that tend to remain above the level of the riflies is retarded and at the same time such particles are guided laterally of the table. The angle of inclination of the wires to the rifiles may be varied through a wide range so long as the conditions above mentioned are satisfied. For best results the nature of the ore and the size of the feed particles should be considered in determining the angle at which the cross wires should be set. However, I have obtained equally good results, in regard to grade of concentrate and impoverishment of tailings, when the wires were set at one angle, and then changed to the diametrically opposite direction, the noticeable difierence being in the increased capacity of the table.

In treating a non-metallic ore, having substantially the same specific gravity as the gangue, such as phosphate ores, when agglomerated into floccules with the capacity of sinking less rapidly in water than the gangue particles, (see my U. S. Letters Patent Nos 1,797,356, dated March 24, 1931), I have obtained highly satisfactory results by placing a set of wires upon the rifiles at about a 225 angle to the riffles so that the .wires extend diagonally across the table from the end away from the point of feed and the head motion towards the point of feed'and the head motion. This provision will hasten the 35 movement of concentrates across the table while retarding their movement lengthwise of. the table. At the same time this makes it possible to accelerate the movement of the sands along the riflies by speeding up the rate of reciprocation of the table. I

A still further improvement in result has been obtained by associating a .set of cross wires, inclined at a 225 angle as above described, with a second set of cross wires inclined at a greater angle to the riflies, and preferably at substantially right angles to the first set, the second set of cross wires being confined to the portion of the table adjacent the point of feed to the table. In this way the movement of the material lengthwise of the table in the zone above the level of the main or primary riffles is still further retarded in the earlier stages of the treatment of the ore on the table when it is desirable to promote a high degree of stratifying action.

tioned within the body of material at least in the portions of the table adjacent the point of feed of pulp thereto. In practice it has been found most advantageous to employ wires of from 12 to 15 B. and S. gauge.

Wire screen of two inch mesh has been used, with inferior results, the junction of the Wires forming the mesh unduly churning up and disturbing the stratification of the bed.

Riiiles with a depth of two or more inches at the head motion end of the table and tapering to 1% of an inch towards the farend of the table, fitted with cross wires, have been used with great success from the point of view of tonnage, such construction facilitating the settling and movement of the sands under the cross wires to the discharge end of the table.

When treating a non-metallic ore, such as agglomerated phosphate, the cross wires. impart mobility to the mineral and gangue particles in the body of pulp on the concentrating bed. The flow of water at right angles toethe riiiles washes the phosphate across the table where it is recovered as concentrates while the sand (gangue) particles settle between the rifiles and are carried along in the channels between the rifiies beneath the cross wires to the end of the .table where they are discharged.

In the accompanying drawings constituting a part hereof and in which like reference characters indicate like parts,

Figure 1 is a plan view diagrammatic in character showing in dotted lines the direction of wires placed on the table, and

Figure 2 is a similar view showing two sets of parallel wires on the table. Figure 3 is a perspective view showing a table of the Wilfley type equipped with an arrangement of crosswires or cross rifles-arranged generally as shown in Figure 2.

Referring .to Figure 1, I have indicated by the broken line 1 a series of wires parallel to each other and spaced a suitable distance apart at the head end i of the table 5, containing a series of riflies 6 which have a maximum depth at the The wires 2 are spaced apart and parallel over substantially the head end of the table, although they may extend over the entire table if desired.

Instead of the sets of wires 1 and 2, I may place a set of parallel wires 3 suitably spaced apart at an angle of about 22.5 to the riflies as shown. With this arrangement I have still further substantially increased the capacity of the table without markedly lowering the grade of the concentrate. k

In Figure 2 I have shown the use 'of two sets of wires 2 and 3: of which the wires 2 are in parallel and at the head end of the table and the wires 3' extend from the furthermost wire 2 to the tails end of said table. The ore is fed at point 7, the tails are taken off at 8, the middlings at 9, and the concentrates at 10. This arrangement I have found to be even more effective in increasing the efiiciency of the table than any of those described above. The wires may be secured to the table in any suitable manner as byftacking them upon the rlffles, or by pinning them at numerous points between each of the rifiles or at a sufiicient number of points so as to hold the wires in their proper relation to the table.' In place of wires, Wire fabric of suitable form and spacing may be used proving it is of such a form as not to disturb unduly the solid particles of the pulp being agitated on the table. The wires need not be directly secured to the table, but may even be independent thereof, but they should be held in such relation to the table as to give them the desired function.

Referring to Figure 3, 11 represents generally a table of the Wilfiey type having a deck 12 equipped with a set of primary rifiles 6 extending generally lengthwise and ending along a diagonal line 6a. Head motion is imparted through a suitable driv-' ing mechanism indicated generally at 13. The ore pulp is introduced through a feed box 14 at the upper right hand corner adjacent the head motion. A perforated pipe 15 for supplying dressing water is shown as disposed along the upper side of the table. Launders 16 and 17 are provided at one end and along the lower side of the table to receive the tails and concentrates. A portion of the launder 17 is shown divided oiT by the partition 18 to receive that portion of the 105,

' sired, on the same level or lower than the corner 22. Tables of this type are generally provided with means, not shown, for varying the inclination of the table laterally and lengthwise according to the operating requirements, and it will be understood that in operation the inclination of the table will be varied as desired.

The following are examples of practice, carrying out this invention in the treatment of phosphate ores, on a James Gravity Concentrating Table:

Carload lots of. phosphate were secured from the Phosphate Mining Company, near Mulberry Florida. A typical screen test shows the'follo ing segregations: V

Per cent On 8 mesh 1 2.8 On 10 mesh 15.4 On 14 mesh 35.8 On'28 mesh 39.0 Thru 28 mesh 7.0

The phosphate was agglomerated into floccules in the manner described in my Patent No. 1,79'l,-

356, and fed to a James standard commercial con- A below:

TEST B Table fitted with cross wires 1, at right angles to the riflles, spaced 1% inches apart. Table feed was at rate of 78 tons per 24 hours Assay %B.P. L. I S102 Heads 59. 10 24. 43 Concentrates... 73. 44 5. 76 a1l 1ngs 5. 71 90. 94 Indicated B. P. L. recovery 95. 0%

TEST C Table fitted with cross wires 2, spaced 1 inches apart, at 45 degrees angle to the riflles. Table feed was at the rate of 126 tons per 24 hours Assay B. P. L. SiOa Heads 59. 85 25.59 Concentrates 75. 40 4. 68 Te1l1n 7. 01 90. 40 Indicated B. I. L. recovery 7.3%

TEST D Table fitted'with cross wires 3, spaced 1 inches apart, beginning at the lower left end of the table, away from the head motion, and extending upwards and across the rifles, at a 22.5

- degree angle to the riflles, to the head motion end. Table feed was at the rate of 149 tons per 24 hours Assay B. P L SiOz 59. 39 26. 88 73. 66 6. 38 Tailings 7. 01 90. 84 Indicated B P. L. recovery. 97.4%

Tss-r E Table fitted with cross wires 2 and 3 (Fig. 2) spaced 1 inches apart. The table was led at the rate of 151 tons per 24 hours Assay B. P. L. SiOz Heads 59. 85 25. 59 Concentrates 74. 16 7. 43 Tailings 5.00 92. 84 Indicated B. P. L. recovery 98.2%

Although I have described my invention setting forth several embodiments thereof, and showing its use in connection with the recovery of phosphate ores, it is to be understood that my invention is not limited thereto. For example, the wires may run in different directions than indicated in the drawings, and may be spaced varying distances apart and may cover varying portions of the table. The wires need not be strictly parallel, and two and even more sets of wires running in different directions may be used. The minerals which may be concentrated by my apparatus are of many characters too numerous to mention here and they comprise practically all of the minerals which are subject to gravity concentration.

I have given figures showing the increase in recovery by the use of my invention, but such figures are not to limit my invention, for example, in Test E, I have obtained a recovery as stated of 151 tons, but in further tests I have been able to feed the table at the rate of 188 tons per 24 hours.

The arrangements of wires which I have described are not necessarily the best for all purposes. but the ideas which I have set forth may be adapted in various forms to various concentrating tables and many ores, so that it may be found that other arrangements than I have specifioally described may be more effective under special circumstances. All such variations constitute a part of my invention which is not to be limited, except by the claims appended hereto.

It will further be understood that in lieu of wires, other wire-like members or strips, constituting riffle elements, may be employed provided they are of such form and so spaced with respect to the primary rifiles as to perform the essential functions of the cross wires in a similar way.

What I claim is:

1. An apparatus for ore concentration which comprises a table, rifiles in the surface thereof, means for imparting motion to said table, and means on said table for increasing the mobility of ore being treated, said means including two sets of substantially parallel wires at an angle to said rifiles, one set being at the heads end of said table and the other set being adjacent thereto, the two sets being at right angles to each other.

2. An apparatus for concentrating ore by wet gravity methods including a normally laterally inclined separating table, riilles extending lengthwise of the surface thereof, means for imparting vibratory motion to said table in a direction substantially parallel to that of said riffies, means for'feeding dressing water to said table adjacent the upper edge thereof, and means superimposed on said ritlles for increasing the mobility of the ore being treated, for retarding the movement of the lighter constituents of the ore lengthwise of said table while permitting the heavier constituents to pass freely along paths defined by said rifiles, and for guiding said lighter constituents off the table in paths transverse to those defined for the heavier constituents by said rifiles, said means being further so positioned with respect to said rifiles as to be disposed in the body of material being fed across said table.

3. An apparatus for concentrating ore by wet gravity methods including a normally laterally inclined separating table, riffles extending lengthwiseof the surface thereof, means for imparting vibratory motion to said table in a direction substantially parallel to that of said riflles,

means for feeding dressing water to said table, and means superimposed upon and extending across said riflles and extending over a substantial portion of the area of said table adjacent the heads end for increasing the mobility of the ore being treated, for retarding the movement of the lighter constituents of the ore lengthwise of said table While permitting the heavier constituents to pass freely along paths defined by said lengthwise rifiies, and forguiding said lighter constituents off the table in paths transverse to those defined for the heavier constituents by said rifiies, said means being further so positioned with respect to said rifiles as to be disposed in the body of material being fed across said table.

4. An apparatus for concentrating ore by wet gravity methods including a normally laterally inclined separating table, rifiles extendinglengthwise of the surface thereof, means for imparting vibratory motion to said table in a direction substantially parallel to that of said rifiles, means for feeding dressing water to said table adjacent the upper lateral edge thereof, and means on said table for increasing the mobility of the ore being treated, for retarding the movement of the lighter constituents of the ore lengthwise of said table while permitting the heavier constituents to pass freely along'paths defined by said rifiles, and for guiding said lighter constituents off the table in paths transverse to those defined for the heavier constituents by said rillles, said means including a plurality of wirelike members superimposed upon said rifiles in angular relation thereto and further so positioned on said table as to be disposed within the body of ore being fed across said table.

5. An apparatus for concentrating ore by wet gravity methods including a table of the type adapted to be reciprocated to feed the ore across the surface thereof, said table including a plurality of substantially parallel rifiies arranged substantially parallel wi h respect to the direc- 1 tion of reciprocation, means forfeeding dressapplication thereof to the table.

ing water to said table, and a plurality of substantially parallel wire-like members overlying an extended area of the rifiies adjacent the point of feed of ore pulp to said table and positioned in the material on the table at a substantial angle with respect to said riflies, the table being in-, clined in a direction generally transverse the rifiles,..whereby, in operation, the concentrate and the tailings are discharged from the table in different directions with respect to the extension of the rifiles, the angularily of the said wire like members being such that they extend generally transversely to the general or mean direc'-- tion of movement of the ore from the point of 6. An apparatus for concentrating ore by wet gravity methods including a table of the type adapted to be reciprocated to feed the ore across the surfacethereof, said table including a plurality of substantially parallel riffles arranged substantially parallel with respect to the direction of reciprocation, means for feeding dressing water to said table, and a plurality of substantially parallel wire-like members overlying an extended area of the rifiies adjacent the heads end of said table and positioned in the material on the table at a substantial angle with respect to said rifiies, the table being inclined in the direction in which the riflles extend and further being inclined generally transversely of said rifiies, whereby, in operation, theconcentrate is discharged from thetable at one edge there'- being treated and for retarding the movement of the lighter constituents of the ore lengthwise of said table while permitting the heavier constituents to pass freely along paths defined by said lengthwise riflies, said means including a series of substantially parallel wires superimposed upon said rifiles at an angle thereto and extending generally transversely of the mean or average direction of material across the table from a point adjacent the point of feed of material to said table over at least a substantial portion of said table, said wires being further so positioned as to move in the material being fed across the table.

8. An apparatus for concentrating ores by wet gravity methods including a substantially rectangular, normally laterally inclined table, riffles extending lengthwise of the surface thereof; means for imparting vibratory motion to said table in a direction substantially parallel to that of said rifiles, whereby the heavier constituents of an ore pulp introduced adjacent one end of the table will be moved along said table to the opposite end thereof and the lighter constituents of said ore pulp will be moved laterally of said said means comprising a series of cross rifiles superimposed upon and extending across said lengthwise riflles toward the lateral discharge side of the table, said series of rifiles covering at least a substantial portion of the table adjacent the heads end thereof and being so positioned as to be disposed within the material being fed across the-table.

9. Ore concentrating apparatus including a normally laterally inclined separating table having a plurality of substantially parallel riffie elements on thesurface thereof and being of a type adapted to feed ore thereacross under the influence of vibratory or reciprocatory motion of the table and of dressing water flowing over the surface of the table, and to discharge separated materials in different directions with respect to the extension of said riflle elements, means for feeding ore and dressing water to said table adjacent the upper side thereof, means forv increasing the mobility of the ore being treated, for retarding the movement of the lighter constituents of the ore in the general direction of reciprocation of the table while permitting the heavier constitucuts to pass freely along paths defined by said rifiles, and for guiding said lighter constituents off" the table in paths transverse to those defined for the heavier constituents by said rifiies, said means comprising a plurality of additional riflie elements superimposed upon said first-mentioned rilile elements and disposed in the path of movement of the material across the table, and further extending generally transversely ofthe general direction of extension of said first-mentioned rifle elements from a point adjacent the point of feed of material to said table over at least a substantial portion of said table.

10. Ore concentrating apparatus including a normally laterally inclinedseparating table of a type adapted to feed ore thereacross under the influence of vibratory or reciprocatory motion imparted to said table and of dressing water flowing over the surface of the table, and to discharge separated materials in different directions with respect to the extension of rifle elements arranged on the surface thereof, said rifle elements being further arranged substantially parallel to one another and to the direction of reciprocation of the table, means for feeding dressing water to said table adjacent the upper edge thereof, and

a plurality of additional rifle elements 'superimposed upon the first-mentioned rifle elements and disposed in the path of movement of the material across the table, and extending over at least a substantial portion of the area of the table and generally transversely of the mean or average direction of movement of material across the table.

11. Ore concentrating apparatus including a normally laterally inclined separating table of a type' adapted to feed ore thereacross under the influence of vibratory or reciprocatory motion imparted to said tableand of dressing water flowing over the surface of the table, and to discharge separated material in different directions with respect to the extension of rifle elements arranged on the surface thereof, said rifle elements being further arranged substantially parallel to one,

another and to the direction of reciprocation of the table, means for feeding dressing Water to said table adjacent the upper edge thereof, and a plurality of additional rifle elements superimposed upon the first' mentioned rifle elements and disposed in the path of movement of the material across the table, and extending over at leasta substantial portion of the area of the table and in a direction generally paralleling the mean or average direction of movement across the table.

12. Ore concentrating apparatus including a normally laterally inclined separating table of a type adapted to feed ore thereacross under the influence of vibratory or reciprocatory motion imparted to said table" and of dressing water flowing over the surface of the table, and to dis-- charge separated'materials in difierent directions with respect to the extension of rifle elements arranged on the surface thereof, said rifle elements,being further arranged substantially parallel to'one another.- and to the direction of recipro- Q: cation of the'table, means for feeding dressing water to said table adjacentthe upper edge thereof, and a plurality of additional rifle elements superimposed'up'on the first-mentioned rifle elements and disposed in the path of movement of" tion of reciprocation, a set of substantially parallel wire-like members overlying an extended area of the rifles and positionedzin the material on the table at a substantial angle with respect to said rifles, and an additional set of substantially parallel wire-like members overlyinganother ex tended area of the rifles and positioned in the material on the table at a substantial angle with respect to said rifles, the table being inclined in the direction in which the rifles extend and further being inclined generally transversely of said rifles, whereby, in operation, the concentrate and the tailings are discharged from the table in diiferent directions with respect to the extension of the rifles, the angularity of the two sets of wire-like memrs being such that the members in one set extend approximately perpendicularly to the general or mean direction of movement of the ore from the point of application thereof to the table and the members of the other set extend approximately parallel to the general or mean direction of movement of the ore from the point of application thereof to the table.

14. An apparatus for ore concentration including a table, rifles extending lengthwise of the surface thereof, means for imparting vibratory motion to said table in a direction-substantially parallel to that of said rifles, means superimposed upon and extending across said rifles and extending over a substantial portion of the area of said table adjacent the heads end for increasing the mobility of the ore being treated and for retarding the movement of the lighter constituents of the ore lengthwise of said table while permitting the heavier constituents to pass freely along paths defined by said lengthwise rifles, and additional means superimposed upon and extending across said rifles and extending over a substantial portion of the area of said table from a point adjacent said first-mentioned means, said means being adapted to retard the movement of the lighter constituents of the ore lengthwise of said table while accelerating the lateral movement thereof.

15. An, apparatus for ore concentration which comprises a substantially rectangular, normally laterally inclined table, rifles extending lengthwise of the surface thereof, means for imparting vibratory motion to said table in a' direction substantially' parallel to that of said rifles, whereby the heavier constituents of an ore pulp introduced adjacent one end of the table will be moved along said table to the opposite end thereof and the lighter constituents of said ore pulp will bemoved laterally of said table, and means for increasing the rmobility of the ore particles adjacent the feed end of the table while retarding the longitudinal movement of the lighter constituents of the ore, said means comprising a series of cross rifles superimposed upon and extending across said lengthwise rifles over a substantial portion of the area of said table adjacent the disposed on asubstantial portion of the area of said table adjacent the first-mentioned set-of cross rifles but more remote from the heads end of said table, said second set of cross rifles being dis-' posed at a substantial angle to the cross rifles comprising said first-mentioned set of cross rifles.

16. Ore concentrating apparatus including a separating table having a plurality of substantially parallel rifle elements on the surface thereof and being of a type adapted to feed ore. thereacross under the influence of vibratory or reciprocatory motion of the table and to discharge separated materials in different directions with respect to the extension of said rifle elements, a plurality of rifle elements disposed in the path of movement of the material across the table and tially parallel rifle elements on the surface thereof and being of a type adapted to feed ore thereacross under the influence of vibratory or reciprocatory motion of the table and to discharge separated materials in different directions with respect to the extension of said rifle elements, a

plurality of rifle elements disposed in the path of movement of the material across the table and extended in a direction generally transverse the mean or average direction of movement of the material, a plurality of additional rifle elements also disposed in the path of movement of the material across the table and extended in a direction generally paralleling the mean or average direction of movement of the material across the table, the rifle elements second mentioned being disposed in advance of the rifle elements last mentioned with respect to the direction of movement of the material across the table.

18. An apparatus for ore concentration which comprises a substantially rectangular, normally laterally inclined table, rifles extending lengthwise of the surface thereof, means for, imparting vibratory motion to said table in a direction substantially parallel to that of said rifles, a series of cross rifles superimposed upon and extending across said lengthwise rifles over a substantial portion of the area of said table adjacent the heads end thereof, said cross rifles being so disposed with respect to the lengthwise rifles as to retard longitudinal movement of the lighter constituents of the ore while permitting the heavier constituents to pass therebeneath along the paths defined by the lengthwise rifles, and a second series of cross rifles disposed at an angle to the first-mentioned cross rifles and extending diagonally across the lengthwise rifles from points adjacent said first-mentioned cross rifles toward the lower side of said table.

' 19. An apparatus for ore concentration which comprises a table, rifles, extending lengthwise of the surface thereof, means for imparting vibratory motion to said table in a direction substantially parallel to that of said rifles, and means on said table .for increasing the mobility of the ore being treated, for retarding the movement of the lighter constituents lengthwise of said table and for accelerating their movement laterally thereof, all while permitting the heavier constituents to pass freely along paths defined by said lengthwise rifles, said means including two sets 'of substantially parallel wires, said sets being disposed at an angle to said rifles and to each other, one set being at the heads end of said table and the other set being adjacent thereto.

RHETHERFORD B. MARTIN.

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