US1323373A - Flotation apparatus - Google Patents

Description

J. F. MYERS. 'FLOTATION APPARATU S. I APPLICATION FILED OCT- 22,1918- 1,323,373. Patented Des. 2,1919.

2 SHEETS-SHEET 1.'

$13 (futon wag,

J. F. MYERS.

FLO TATION APPARATU S.

APPLICATION FILED OCT. 22. I918.

Patented Dec. 2, 1919.

2 SHEETS-SHEET 2.

' JOHN F. MY RS, or canyon CITY, COLORADO, ASSIGNOR TO THE NEW JERSEY zmo,

V COMPANY, on NEW YORK, v. v., A CORPORATION-OF NEW FnoTA'rIoN-APPARArUs. V

. ."Snecifieation of-Letters Patent.

I Application filed October 22, 1918. Serial No.'259,200.

. o all wh'omit ma h' y 4 Be it known thatv I, JOHN MYERS, a citi zen of the United States, residing at Canyon City, 'in the,county of. Fremont, State of, Colorado, have invented-certain. new and .useful- Improvements in =Flotation Appara- 1 ms; and I do hereby declare the following to be a full, clear, and exact'de'scription ofthe invention, such as will enable others skilled in-th'e art to which it appertains to make and'use thesame;

This invention relates to an apparatus for f -9, so 'that the air mtroduced therethrough *acts' 111'; these. respective compartments and 'theconcentra'tion of minerals in accordance with the so-called flotationprocess. 15

.The apparatus of the present invention is made up of a plurality of compartments or cells of annular or other contour surround ing each other and so arranged with respect to each other that the froth from one'cell. is fed to the'next, and thetailings are fed. fromJone cell to another incounter current v tothe flow of the froth.

The invention will be further described in connection with the "embodiment thereof,

illhstrated in the accompanying drawings,

V -in which Figure 1 shows, in central, vertical section 1 an apparatus embodying the invention, the

illustration being, in part, of a conventional character; Fig. .'2 is a plan of the same apparatus; Fig. 3 is an enlarged deta1l showing one form of construction of the porous bot tom of the apparatus; Fig. 4 shows in central, vertical section, another form of app-aratus embodying the invention; 'Fig'. '5 is a. plan of the apparatus of Fig. 1; and 6 is an enlarged detail showing the'form of air bottom' used in the apparatus of Fig. 4.

The,apparatusillustrated in Figs. 1, 2 and 3 is made up of the four concentric walls 1, ,2, 3 and 4 suitably-connected. at their lower ends. Depending within the compartments formed by these concentric walls are concentric walls 5and 6, which extend 'nearly to the bottom of .the compart- *ments, but are spaced away therefrom These depending walls may be supported in any suitable manner (not shown). The arrangement of the concentric walls issuch that there are formed three annular flota- -tion. compartments 7, 8 and 9, and two an- 'nular inlet compartments l1 and 12. Inside the central annular wall 4 is the central compartment 9. By this arrangement, the

provided a. series of airc'hambers'13'-cov'-' ered by a porous bottom 14: of any suitable" construction andsu-pplied by air through air In .the'bottom 'of the; apparatus there I ply pipes 15, each of which has an i I I, dentcontrol valv 16 and each of which I,

5 is protected ,by a baflle plate or distributor 1'7. 1 These air chambers do notextend over- .the entire bottom of the a pp-aratus,but are localizedibeneath the compartments 7 8 and does not act in the overflow orfeed corn partments 11 and Bafiies or bottom" plates-l8 are-provided at the bottom of the compartments 11 and 12 to form the bottom thereof and to aid in directing-theflow of the pulp from'the compartments 11 and 12- to the adjoining inner compartments.

The concentric walls 2 and 3 are provided near the'lower end thereof with check valves 19 and; 20, through which communication is afforded for circulation. of the orepulp from both of the inner compartments B and ,9 to

the neXt-adjacentcompartments 7 and 8 -re.-;,.-'

spectively. structed so as to -permit the ,pulp to flow from-the inner compartment to the adjacent outer 'compartment,'and so as to prevent any flow of pulp therethrou'gh'inthe opposite direction.'- Thus, the check valves 19, of

which there may be 'a suitable number, perto compartment 7, but not from compartment 7 to compartment 8. check valves 20 are-constructed so that the. pulp -can go frdin compartment 9 to compartment 8, butnot from compartment Sto ore pulp can flow through the various compartments in only one direction, to wit, from The check valves are so con-Y 'm'it the pulp to travel from compartment 8 Likewise the I the innermost compartment toward the outermost compartment.

A- partition 21 is provided in the outer compartment 7.' An outlet, 22 is arranged on one side of this partition and communicates withl the compartment. 7 below the normal liquid level therein. An inlet 23 is arranged on the other side of the partition 21.

Stirrer rods 24 carriedby arms 25 are provided for assisting in breaking up the froth necessary or desirable, these stirrersbeing rotated slowly in any suitable manner, as by means of the bevel gears 26. -The stir rers' and driving means therefor may be supported in any suitable manner (not shown); v e

As above noted, the perforated bottom 14 may be of any suitable construction, such as iscommonly employed in flotation apparatus of the character where air is intro duced through a porous bottom into the flotation ,cell. One suitable form of porous bottom is shown in the-enlarged viewof Fig. 3, this bottom being made up of a coarse screen cloth 29 with a layer of finer cloth supported thereon and with metallic shot or spherules supported by the upper cloth of suflicient-fineness and depth to effect a uniform distribution of the enter ing air. The-metallic spherules' may, for

example, vary insizefrom- 0.08 inches to 0.03 inches diameter, or from about No. 9 .to.fine dust, American standard. 2;.The depth oflthe layer of spherules or shot mayyary, for example, from one-half 'inch-ytQ pm; or twoinehes,

vWhen the apparatus is inlnor'mal opera- 'tion, the outer or first flotation compartment or cell 7 is the rougher cell, while the inner'flotation compartments or cells 8 and v9 are the cleaner; and re-cleaner cells, re-

spec'tively. The nermal operating condition of the 'apparatu'siw rnay be. initiated in any suitable manne'n' as, for example, by feeding the ore pulp to all three: cells or com-. partments and o crating the apparatus, as hereinafter described, until the intermediate and inner cells 8 and 9 are in. proper condition to operate as cleaner and re-cleaner .cells, respectively."

After the apparatus is in norn1al pperation, the ore pulp is fed to the first-cell 7 of the series through the inlet 23. The levelofthe pulp can be determined in any suitable mannenas by means of a, float-control inlet (notshown). Air is introduced through the pipes 15 to the air compartments 13 and is discharged through the porous bottom 14 into the. respective compartments 7, 8 and 9 which thus form flotation cells or compartments. The froth formed in the compartments 7, 8 and 9 over'-. flows the inner annular. walls '2, 3 and 4,

which terminate at progressively lower levels, so that ,the froth is re-treated in the inner compartments, and finally discharged into the central outlet compartment 10.

The froth fdrmed in the outer or rougher flotation cell 7 overflows into the annular chamber 11. This overflow froth from the rougher cell 7.then forms the feed of the second or middle flotation cell 8, which thus acts as a'cleaner cell, and the froth therefrom. overflows in. a similar manner intothe annular chamber 11, from whence it is fed into the inner cell or compartment 9, which serves as a rercleanercellp The froth from the re-cleaner cell 9 overflows into the central compartment 10 and is conducted therefrom to any suitable plaeefor further treatment or storage. The stirrers 24 when k up the o erflowing froth, in case such breaking up 1s necessary.

used, serve to brea 'The froth formed in the outer cell is retreated in the next inner cell, and the froth of the latter is in turn re-treated in the inner cell, while thetailings from the inner cells flow outwardly and are similarly retreated. v.

T e arrangement ofthe inlet 23 and of the outlet 22- is suchthatthe entering pulp is distributed around the outer compartment 7, and so that the tailings' escape gfrom this compartment through the ,outlet 2'22,- which is arranged on the QDosite side'of the -partition 21 from the inlet- 23. The ore, pulp thus flows around the outer annular compartment or flotation cell from the inlet 23 to the outlet 22. WVhile the pulp is thus flowing through this outer annular compartm'en't it'is continuously and everywhere throughout the compartment subjected to a flotationtreatment. The rough froth overnowing from this outer flotation cell is retreated in the intermediate or cleaner cell 8, and the tailings from this second flotation treatment-escape from the cleaner. cell through the check valves 19 into the outer cell, while the overflowing froth is subjected to a further flotation treatment in the inner cell 9". The tailings from this last flotation treatment escape t rough the check valves 20 into the intermediate flotation cell 8,'

where thev a ain undergo the flotation treatpower is required for the operation of the" apparatus inasmuch as the transfer of the froth from one part of the apparatus to another takes place by overflow, and inasmuch as thetailings flow by -gravity in the reverse direction. Centrifugal pumps or other apparatus for conveylng the froth or concentrate and the tailings from one flotation machineto another are unnecesary' The compressed air supplied to the apparatus may be obtained in any convenient manner, such as is common in the art, and it may be lntrod'uced under a regulated presj sure. so that the operation of the apparatus.

can be thereby controlled; Each of the air pipes is provided with a regulating valve so I that each of the compartments 13- can be innumber of independenta r compartments dependently regulated. For convenience of distribution and regula'tioneach of the flotation cells 7,- 8 and 9 is provid'edwitha large 13 separated from each ,other by partitions indicated by dotted lines 32 in Fig. 2. Each of the air compartments 13 may also be provided with draw-ofi openings or pipes (not shown) for permitting the draining of these respective compartments in case of necessity therefor.

Where the apparatus is made with a larger or smaller number of flotation cells or compartments, the apparatus will nevertheless operate in the same manner, with progressive enrichment of the concentrate and progressive impoverishment of the ore pulp. So also ifthe apparatus is made anything other than circular in form and with concentric cells or compartments, it will nevertheless retain its characteristic moue of operation and simplicity of structure. The circular and concentric'arrangement of the flotation cells is, however, of particular advantage, since by such an arrangement the cellsmay be conveniently designed of progressively decreasing size corresponding to the progressively decreasing amount of ore pulp which each succeeding cell must handle' Thus the circular and concentric arrangement of the flotation cells provides a very compact structure in which each. inner cell is of progressively smaller capacity than the next adjacent outer cell.

In operating the apparatus, the quantity of material overflowing the-wall'2 is larger than that overflowing the wall 3, and hence ther is always a tendencyffor the liquid level in compartment 8 to be higher than the liquid level in compartment Z, and this difference in hydraulic head keeps the check valves 19 open under normal operating conditions, thereby permitting the ore pulp or 1 rat us embodying the invention.

tailings to flow through'the check valves 19 from compartment 8 into compartment 7. Similarly, the quantity of material overflowing the 'wall. 3 is larger than that over-- flowing the wall 4, whereby there is established between the compartments 9 and 8 a 7 difference in hydraulic head which, under ment 7-fr'om getting into the cleaner cell or compartment 8. lfrothlis overflowing the wall 2 into the com- And again, in case no p partment 8 for a short period of time, while froth continues to flow over the wall 3 into compartment 9-, causing the liquid level in compartment 8 to. become lower than in compartment 7, no flow of pulp can take place fromlcompar tment -7 into compartment 8, because, under such conditions, the check valves19 remain closed. The same prinCi-. ples obyiously apply to the two compart- I ments 8 and 9. It will furthermore be evident that the arrangement of check valves facilitates starting ,up theapparatus, when empty. Y

In Figs. 4, 5 and 6 of the drawings, there is shown a slightly modifiedform if appa he apparatus comprises three concentric compartments 7, 8 and 9, having froth overflow walls 2', 3' and 4' respectively. The walls 2, 3 andv 4' are of substantially the'same height, andnot progressively lower, as inthe modification of Fig. 1. The depending concentric walls 5- and 6." are preferably higher than the walls 2, 3 and 4, so as to direct the overflow froth into the froth in- 110.

let compartments 11 and 12, and so as'to. prevent any backward flow of the froth. Thewalls 2' and 3'have near their bottoms check'valves 19' andQO, of the same character as in the apparatus of Fig. 1.

. Circular water spray pipes 35 and 36 are arranged above the froth inlet com:part--.

This porous bottom is in the form of an air grate composed of pipes 37 drilled with holes to provide air exit apertures. ,Each pipe 37 is covered with a layer 38 of canvas,

or equivalent material. The pipes 37 :are spaced apart to permit the passage of material through the grate. The air grates are the art.

so positioned that the air coming from the pipes intothe' flotation cells has no opportunity 'of passing into the froth inlet pompartments; 11 and-"12. In an-air grate of this type which I" have successfully operated, the pipes 37 were half-inch pipes suit-- ably drilled with holes and covered with canvas. The pipes were 'spacedil/ l inch apart. In the drawings Iihave shown the pipes 3-7 as circular and: extending pletely' around the flotation."cells, but it will of course be understoodthat the pipes may be sector-shaped and arranged in sections, and that more than one air inlet 39 may be provided.

The operati-on'of the apparatus of Figs.

4, 5 and 6 is substantially the same as'de-fl scribedin connection with the apparatus of Figs. 1, 2 and 3. It, is, accordingly, be-

lieved that no-further explanationof the modified construction is necessary, and that its operation will be clear to those skilled in From the foregoing description it willbe seen that in the apparatus of the invention a plurality of flotation cells are arranged in series. The first cell of theseries is the rougher cell from which the overflow froth.

passes by gravity to the'next adjacent cell in the series. The last'cell'of the series is .the cleaner cell from which the overflow froth is collected and the tailings passed by gravity to then'ext preceding cell .in. the

series. "In the intermediate cells of the series the overflow froth. and tailings flow in counter-current, the overflow froth passing by gravity toward the last cell in the series and the 'tailing passing by gravity toward the first cell in the series. Thus, in the apparatus of the invention the raw mineral 4 pulp to be treated is fed to the first cell of tion treatment 'inthis cell.

- I claim: 7

1. 'Afiotation apparatus comprising a plumay of flotation cells surrounding one another, each of-saidcells being provided with the series-and is subjectedto the first flota- --a porous bottom for the. introduction of air,

said cells being arranged vso that the froth overflows from one cell toanother and so that the tailings escape from one cell to another in the reverse directionto. theflow of the froth. 5 I

2. A flotation apparatus comprising a plurality of annular flotation fcells concentri cally arranged,"each of said cells having a porous bottorn'for the introduction of air,

said cells being arranged so as'to direct the froth overflow of each cell into'the next-adj acent inner cell and so that the tailings of each cell escape intothe next adjacent outer celL- v is a porous bottom for the introduction of air, 1 the innerwalls of said'cells' being progres- 1 sively lower so as to permit the progressive overflow of froth from the outer-most cell to the inner-most cell, and means for directair, the inner wall of each'of said cells be-- ing into each of the inner of said compartsively lower so as to direct the overflow froth from each flotation compartment to 3. A flotation apparatus comprising-a plurality of annular flotation cells concentrically arranged, each of said'cells being provided with aporous bottom for the introduction of air, intermediate annular compart- 7 ments' arranged between adjacent cells and adapted. to receive the overflow froth from the adjacent outer cell and to feed such froth into the adjacent inner cell, and means permitting the escape of tailings from each inner cell to the adjacent outer cell.

, 4.;A flotation apparatus comprising a plurality of. annular flotationcells concentrica'lly arranged, each of said cells having next adjacent-inner cell. 3 v

5. A flotation apparatus comprising a plurality 'of flotation cells surrounding one an' other, each of said cells being provided with a porous bottom for the introduction of" ing lower than the outer wallthereof and also lower than the inner wall of'the next adjacent outer cell, rneans for directing the froth overflow of each cell intothe next ad-. jacent inner cell, and means for: permitting 'the escape of'tailings from each inner cell to the'next adjacent outer cell.

6. A flotationapparatus comprising a plurality of concentrically arranged annular compartments, each of said compartments having 'a porous bottom arranged for the introduction of air,a circular wall depend ments and arrangedto divide" such compartments into a froth inletcompartment and a flotation compartment, the inner walls of said annular compartments being progresthe adjacent froth inlet compartment, andmeans for permitting the escape of tailings from each. of said annular compartments to the. pext adjacent outer annular compartmentf 1 1 7. A flotation apparatus comprising a series of flotation cells, each of said cells beingprovided with a porous bottom for the introduction of air,-means for feeding the ,raw ore pulp to be treated to the first cell each cell to the 85 Y op erativelylarranged in series so that the r by each cell intermediate the first and last cell in the series subjects the overflow froth of the preceding cell in the serles together with the tailings from the succeeding cell in the series to a flotation treatment, andmeans for feedingrthe raw ore pulp to be treated and for withdrawing the exhaust tailings of said apparatus from the first cell-in said series.

10. A flotation apparatus comprlsmg' a plurality of flotation cells, saidcells being operatively arranged in series, and means forfeeding by gravity to each cell intermediate the first and last cell in said series the overflow froth from the next preceding cell in the series and the tailings from the next succeedin cell'in the series.

11. A flotatlon apparatus comprlsmg a plurality of-flotation cells operativelyarranged in series, means for feeding the overflow froth of each. cell, except the last cell inthe series, to the next succeeding cell in the series, means for permitting the escape ,by gravity of the tailings of each cell, except the first cellin the "series to the next preceding cell in the series, means for collecting the overflow froth of the last cell in the series, and means for fe'edin the ,raw ore pulp to be treated and. forgwi drawing the exhaust tailings of said apparatus from the first cell in said series. I 12. A flotation apparatus comprising a plurality of flotation cells operatively arranged 1n series, means for feeding by gravity the overflow froth of each cell in said treatment.

series, except the last cell thereof, to the next succeedin cell in the series, means for permitting t e tailings to escape .by gravity from each cell in said series, except the first cell thereof, to thenext preceding cell in the series, and means for subjecting the overflow froth and tailings in 13. A. flotation cell in the series and the tailings from the next succeeding cell in the series, and means overflow froth from each of said cel each'cell to a flotation apparatus comprising a plurality of flotation cells operatively arfor feeding the rawore pulp to be treated andfor withdrawing the exhaust tailings .of

said apparatus from the. first cell in said series.

14.'A- flotation apparatus comprising a plurality ofannular flotation cells concenpartments arranged between adjacent cells and adapted to receive the overflow froth from the adjacent outer cell and to feed such froth,into the adjacent inner cell, and rotary 'stirrers associated with said intermediate trically arranged, intermediate annular comof air, a circular wall depending'into each of said annular compartments, except the outer thereof, and arranged to divide such compartment into a froth inlet compartment and a flotation compartment, the inner walls- .of said annular compartments being pro-.

gressively lower from the outer to the mner so as to permit the progressive flow of froth from each flotation compartment to the next inner adjacent inlet compartment, and. a rotary stirrer in each of said inlet compart-e' ments. Y 1

16, A flotation apparatus comprising a plurality of annularflotation cells concentricallyarranged, said cells being arranged so as to direct the froth overflow of each cell into the next adjacent inner cell and :so that the tailings of each cellescape into the next adjacent outer cell, and means for feeding the ore pulp to be treated to the-outer of said cells and for withdrawing from said same cell the exhaust tailings of said apparatus.

17. A flotation apparatus comprising a plurality of annular flotation cells concentrically arranged, means for feeding the overflow froth from each of said cells, except the innermost one thereof, tothe next adja- -cent inner cell, and'means for breaking up the froth overflowing from one cell to another. Y

18. A fiotatlon apparatus comprising a plurality of annular flotation cells concenof, to the next adjacent outer cell, and means for feeding the ore pulp to be treated and for withdrawing the exhaust tailings of said apparatus fromthe outermostcell thereof.

In testimony whereof I aflix my si attire.

, JOHN F.M RS.

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