US2916213A - Ore beneficiation process and apparatus - Google Patents

Description

P. L. PAULL ORE BENEFICIATION PROCESS AND APPARATUS Dec. 8, 1959 2 Sheets-Sheet 1 Filed March 3, 1954 Dec. 8, 1959 P. L. PAULL 2,916,213

om: BENEFICIATION PRocEss AND APPARATUS Filed March s, 1954 2 sheets-sheet 2 United Se@ Patient* oRn BENEFICIATION PROCESS AND APPARATUS Peter lL. Paull, Norwalk, Conn., assignor to Texaco Dev'elopment Corporation, New York, N.Y., a corporation of Delaware Application March 3, E1954, Serial No. 413,806

2'5 Claims. (Cl. 241-5) The present invention relates to a novel method of and apparatus. for beneiiciating -ore Aso as vto separate particles which are richv in desired components from those that are poor.

Briey, my novel method involves first forming a flowable mixture such as a slurry of relatively coarse particles of an ore in a vaponzable liquid such as water, continuously passing this slurry into an initial portion of an elongated uid conduit, heating the slurry to vaporize liquid and form a dispersion of solid particles in hot vapor such as steam, and passing the resulting dispersion through a latter portion of the fluid conduit at high velocity in turbulent ow to cause the particles to impinge against one another and disintegrate to relf atively ne particles, some of which are rich and others poor in the desired mineral. Y

The fine ore particles are continuously fed from the fluid conduit to a separator wherein the rich particles are separated from the poor and collected as a concentrate. Separation can be accomplished in any suitable way, as by magnetic separation when there is a substantial difference between the magnetic attractabilities of the rich and poor particles, or by flotation wherein the rich particles are separated from the gangue on the basis of dif' ferences in their real or apparent specific gravities in a liquid such as water.

My invention is highly advantageous because it is a rapid, economical, and continuous integrated operation combining size reduction of the'ore with concentration of the desired mineral. Also, as will appear hereinafter, the invention is surprisingly eicient because it incorporates various steps involving the multiple utilization of process fluids in different, parts of the method, and the recycling of rejected middlings to improve recovery. Another important advantage is that size reduction of the ore can be accomplished with but little wear on the apparatus, and in such a way that contamination of the ore with undesirable ingredients is avoided.

In the drawings:

Figs. l, 2, and 3 are schematic ow diagrams showing three modifications of apparatus for performing one embodiment of the invention, wherein size reduction is cornbined with flotation for the separation of rich particles from poor; and

Figs. 4 and 5 are schematic flow diagrams showing two modifications of apparatus wherein size reduction is combined with magnetic separation.

In the following description the slurry liquid is exemplied by water, but under some circumstances other liquids such as petroleum distillates or liquid refrigerants can be used. Examples of the former are kerosene and lubricating oil. Examples of the latter are ammonia, sulfurvdioxide and propane.

As shown in Fig. l, ore particles which have been previously crushed in a jaw crusher to a' relatively coarsev Patented Dec. 8., 1959 considerably but generally is less than 2:1 by volume, often being 1:1. Continuous feed of ore particles and Water to tank 11 in the selected proportions is advantageous.

This slurry is pumped continuously by a pump 13 at a linear velocity of 1/2 to 10 feet per second into the initial portion of an elongated conduit or tubular zone, including a long heated tube 17 located within a heater 19 which may be tired in any desired way, as by oil or gas. Tube 17 can be coiled, or in the form of parallel straight tubes connected together by return bends, so as to effect space economy in heater 19; and the tube may be composed of two or more sections located in several individual heaters.

In the initialportion of tube 17 the slurry is rapidly heated to a temperature above the boiling point of Water and a dispersion of coarse ore particles in steam is formed. This dispersion passes at a high velocity in excess of feet per second, through the latter portion of the tube 17 and continues through a pair of branch tubes 21 and 23 from which it is discharged as a pair of opposed mutually impinging high velocity jets through a pair of diametrically opposed nozzles 25 and 27 located Within a low pressure grinding chamber 29. Tubes 21 and 23, and nozzles 25 and 27 constitute part of the tubular zone along with tube 17. Velocity in tube 17 advantageously is kept below 100 feet per second to reduce erosion of the tube by the solid particles, but much higher velocities may be used where erosion is not an important factor.

Some size reduction occurs as the result of turbulence and mutual impingement of particles on one another before the ore particles reach the nozzles, but most of the grinding results from impact of the two jets against one another due to the high velocity and turbulent ow which causeparticles to collide with great force. Relative velocities of the two jets are double that of a single jet, yet erosion difficulties are avoided because impingement reduces velocities below detrimental values before the particles strike the walls of the grinder. Particle sizes of the ground ore are such that substantially all pass through a 200 mesh U.S. Standard screen (-200 mesh), and many-are as line as 5 microns.

From grinding chamber 29 the dispersion of ultra-fine particles in'steam then passes by way of a conduit 31 to a condenser 33 wherein condensation of the dispersion back to a slurry is accomplished by passing a cooling liquid such as water into the condenser through a conduit 35 and out through a conduit 37 for indirect heat exchange with the dispersion to reduce its temperature below the boiling point of water, say to a temperature between and 180 F.

The hot reconstituted slurry then ows through a con-- duit 39 into a flotation machine tank 41 to form a pulp which is -agitated violently by mechanical stirring and/or by the bubbling of gas such as air therethrough. Air

' is supplied by a conduit 43 and distributed through a porous septum `45 forming the bottom of the tank and inclined toward one side for the accumulation of settled unfloated material. A froth -47 forms on the top of the liquid pulp 49 and carries therewith one of the compo-l nents of the ore, usually the rich one, this froth being continuously removed by flow into a trough 51. The settled material at the bottom of the tank, usually the poor particles or gangue, is removed as a slurry through.

a conduit 53.

It is often found that the settled gangue leaving through conduit 53 still contains some valuable minerali; content. This can be recovered by pumping the gangueA slurry through a conduit 54 back to the slurrytank 11 to mix with fresh slurry and be recycled as described,` above, whereby the sangue particles are reduced still further in size. Alternatively or concurrently, 'gangle slurry may be injected into the dispersion in heater tube 17 through a conduit 56 to cause shock cooling and rewetting of the solid particles, whereby size reduction is accentuated. Suliicient heat is supplied to vaporize the liquid after the rewetting.

In general the desirable concentration of solids in the pulp within` flotation tank 41 will be less than in slurry tank 11. Therefore, when the reconstituted slurry is passed into tank 41 it may require dilution by the addition of water to reduce the concentration of solids to about Ztl-40% by volume. Dilution is readily accomplished in an ecient and economical manner with the condenser heat exchange liquid, as by passing it through a conduit 55 into the conduit 39 in amounts regulated automatically byyconventional flow controllers.

Separation by flotation occurs more etfectively at high temperatures than at low because a rise in temperature normally increases reaction velocities; aids completion of reactions involving decomposition, solution of solids, or formation of gas as one of the reaction products; and reduces the viscosity of flotation agents such as oils, thus aiding coating of ore particles. Such a relatively high temperature, of course, is an important advantage of the method described above wherein high temperature grinding is employed and a slurry is passed at a high temperature into the flotation machine.

An important factor in froth flotation is the employment of suitable addition agents in the pulp to cause selective separation of rich and poor ore particles by means of a froth which acts to float off some particles of ore while permitting others to sink to the bottom. Among such addition agents are collecting agents, conditioning agents, and frothing agents, specific examples of which are well known to the art as described on pages 12-03 to 12-47 of the Handbook of Mineral Dressing by Arthur F. Taggart, published by John J. Wiley and Sons, Inc., copyright 1945. Such agents can be continuously added by feeding them directly to the flotation tank 41, or by incorporating them in the initial slurry in tank 11 for passage through the grinding portion of the system before entering the flotation tank, or by introduction at any intermediate point. By incorporation with the slurry before vaporization the individual particles lcan -be uniformly coated. The quantity required yis very small, generally ranging from 0.05 to 1.0 pound per ton of pulp under treatment.

Example I Referring to Fig. 1, concurrent grinding and notation concentration 'of molybdenite illustrates the present invention. vAn 89% by weight slurry of 14 mesh molybdenite ore in water is passed at a rate of 3300 pounds per hour through 800 feet of '1K2 inch heater pipe 17 (arranged in four heaters as parallel straight pipes connected by return bends) to an opposed jet grinder 29 having 3A6 inch LD. (inside diameter) nozzles and thence to a condenser 33. Air is bled into heater pipe 17 through conduit 57 to condition the molybdenite.

Thepressures in pounds per square inch are 1100 at the entrance to the heater pipe, 543 at the nozzle inlets, and atmospheric at the condenser. The temperature at the nozzle inlets is 751 F. The velocity ahead of the nozzles is about 100 feet per second, but sonic Velocity is reached in the nozzles.

The L200 mesh ground ore slurried in water from the steam condensation is then passed to a ilotation tank 41 to which is continuously added enough water from conduit y55 to reduce the ore concentration to 30% by volume. Also there is continuously added to thepulp in 'the lflotation tank 4a mixture of C-Cm aliphatic alcohols, fuel'oil, andpine oil (424:2 parts by'volume, respectivelylat a rate of 0.5 pound per ton of pulp.

fAgitatio'n of the pulp by air effects the desired otation of `molybdenite particles from the gangue particles.

zetema i f Referring to Fig. of the drawings, a grinder 29' identical with that of Fig. l is preceded by identical heater tubing and slurry tank equipment, which have been omitted for simplicity. The dispersion from grinder 29 ows through conduit "31 into a centrifugal separator 61 such as a conventional cyclone separator within which all or part of the steam or other vapor is separated and passes off the top through a conduit 63.` Solid material passes out the vbottom through an outlet `65, is picked up by a stream of water from a conduit 67, and carried through a conduit 69 into the flotation tank 41 for concentration of the mineral. Y

Separator 61 is provided with external condensing' coils 71 which can be supplied with cooling water through a conduit 73 leading from the conduit 67 on the upstream side of a control valve 75 and then connected back into conduit 67 downstream of valve 75. With this construction a part of the steam can be ondened in separator l61 so that'a wet mass of ground ore is def livered through outlet 65 for better mixing with the diluting water from conduit y67 prior to entering tank 41'.

The steam leaving the top of separator l61 passes by conduit 63 to an air aspirator 79 wherein a substantial volume of air is aspirated and passes with the steam through conduit 81 and a conduit `8.3 into the void 85 below a porous septum 87. The mixture of steam and air then passes through the septum to agitate the pulp 89 and cause separation of the ore `ingredients by iiotation. Auxiliary air may be supplied through conduit 91. Sometimes agitation by the steam alone is sumcient, and then the aspirator 79 is eliminated and steam alone enters void 85.

As in Fig. l, foam laden with mineral particles is taken oi the top by a trough 51'; and settled particles in slurry form are taken .olf the bottom through a conduit 53' and may be recycled to the slurry tank and/or heater tube if desired.

Referring .to Fig. 3 of the drawings, a `grinder 9,5 is supplied with a dispersion in the manner of Fig. l. Grinder is a convergent-divergent nozzle which takes the relatively low velocity dispersion from conduit 17 and accelerates it tremendously so .as to develop supersonic velocity (greater than `1000 feet p er second) and great turbulence whereby the solid particlesimpinge forcibly against one another and are reduced greatly in size. The -powdered dispersion then passes to a centrifugal separator 97, such as a conventional cyclone, which is so designed as to separate out oversized solid particles which leave the bottom throug'han outlet 99 and can be returned Vto theslurry tank and/ or heater tube for repetition of the lgrinding cycle, if desired. 'The dispersion of fine particles in steam passes off the top through a conduit 101 and is delivered to agenerally'horizontal header 1013 having 'a plurality of nozzles '105 for passing the dispersion into the bottom o'f the pulp 107 'in a tlotation tank 109. Auxiliary cold water to reduce the concentration of the slurry is added through a conduit '1.11. Froth and settledparticles are removed as described prerviously.

In the Fig. 3 modilication uniform distribution of the solid particles inthe pulp 107 is obtained while the steam concurrently agitates the pulp and 'heats it so as to effect an efficient flotation operation. `Much of the steam, of course, vis condensed in the pulp.

Example II Referring to Fig. 3, a 59% by weight slurry of 14 mesh apatite orein water is passed ata rate of 1732 pounds perhour through 800 feet of l inch heater pipe, as in Example I, to a convergent-divergent nozzle 95 having a 1A inch throat, `and .thence toa 4 Ainch I.D. scalping cyclone97. vr1`he pressur;es sin pounds ,persquare inch. are 1'092 at .the entrance to .theheater pipe, 578 at the'nozzle inlet, and .l0 .at the cyclone. The tempera- UfQC the nozzle 'inlet Jis.7 5 0 F ,at the cyclone entrance 15 741 F., and at the bottom' of the cyclone 700 F. Supersonic velocity is reached in the nozzle.

The scalped steam dispersion of -200 mesh ground ore from the top o-f cyclone97 then flows into a llotation `machine 109 to which is continuously added enough cold water to reduce the ore concentration to 28% by volume. Also there is continuously bled into the pulp at a rate of 0.2 pound per ton of pulp a flotation reagent formed by 2 pounds tall oil fatty acid, 4 pounds light fuel oil, 1/2 `pound of caustic soda, and `1 pound of turpentine. The concentrate of phosphate is iloated oli while the gangue settles to the bottom.

By way of illustration the principles of that portion of the invention involving flotation have beendescribed `above with reference to froth llotation. It is evident, however, that theyfalso apply to other types of flotation such as skin llotation, bulk oil flotation, and granulation.

VVThere are many. different types of ores 4which can be concentrated by the combined grinding and ilotation methods described above. In general, if two minerals diier to the extent that one contains a substantial amount of a particular metallic element or acid ion which is absent in the other, the two may be separated by flotation. Forexample, single orv mixed suliides can be separated from the usual rocky gangues. The oxidized heavymetal minerals and the rocky mineralsof the non-silicate series can be separated from each other and from the silicate minerals. 'Coal and graphite are readily separable from the rock-forming minerals. Quartz and `other silicates can be lloated in the presence of metallic oxides and mineral salts of the alkaline earths.

Among specific sulfide minerals which can be concentrated by flotation are cinnabar, copper suliides, chalco-V cite, chalcopyrite, galena, and molybdenite. Others, of the non-sulfide variety, are native metals such as gold, silver and copper; and such oxides as bauxite, cassiterite, chromite, manganese oxides, iron oxides, rutile, alunite, cerussite, scheelite, vanadinite, calcite, dolomite, lluorspar, and 'various phosphates such as apatite and podolite.

Silicates also can be concentrated by flotation, for exi ample andalusite, 4beryl ore, brucite, feldspar, mica, and

kyanite.

Oxidation is a form of activation for suliide minerals often employed as a preliminary to flotation. When using the present invention on sulfide ores, such oxidation can be accomplished readily in the heater tube 17 by bleeding in air or oxygen through a conduit 57 to react l with the sulde and prepare it for ilotation.

Fig. 4 shows an arrangement of apparatus wherein an integrated combination of grinding and magnetic separation of the ore is accomplished. A slurry of about 50% ore in water by volume is made up continuously in a slurry tank 115 and pumped through a conduit 117 into the initial portion lof an elongated iluid conduit comprising a tube 119 located Within a heater 121 fired in any desired way, as by oil or gas, all as described in connection with Fig. l As the slurry passes through tube `119 water is vaporized to form in the latter portion of the tube a dispersion which ilows at a velocity in excess of 25 feet per second to a grinder 123 comprising a convergent-divergent nozzle forming a part of the lluid conduit. Supersonic velocity and great turbulence are thus produced in the nozzle and the particles are disintegrated by collision with one another.

The dispersion then passes through a conduit 125 into a centrifugal vseparator A127. Steam leaves at the top of separator 127 through a conduit 129, while substantially dry ground ore leaves the bottom through a conduit 131 and enters a rotating cooling drum 133 over the outside of which water is sprayed by a series of distributing nozzles 135 to cool the ore down to a'temperature preferably below 100 C.

From drum 133 the ore enters a hopper 135 and passes onto the periphery of a magnetic separator drum 137 whichrotates counterclockwise while a magnet 139 within the `drum rotates clockwise. The relatively nonmagnetic middling .material is carried counter-clockwise and ilows offvthe side of the drum into a receptacle 141, while the magnetic concentrate is carried clockwise and taken off the other side of the drum by a clockwise rotating magnetic collector wheel 143. Several suitable dry magneticl separators are described in the aforementioned Taggart volume on pages 13-15 to 13-l9.

Some ores contain a mineral which is not suiciently magnetic as mined, but which can be converted to a more magnetic condition by a suitable roasting treatment. This can be readily accomplished in my method by introducing through a conduit 145 into the latter portion of the heater coil 119 a suitable gas such as air, oxygen, nitro-gen, or a reducing atmosphere such as hydrogen, carbon monoxide, or natural gas so as to react with the ore at the high temperature of the coil.

Hematite can be changed to magnetic Fe304 by extrac- -tion of the oxygen at temperatures ranging between 370 and 600 C. This can be done by strong heating in the air, less heat in a reducing atmosphere, and still lower heat when there is intimate admixture with a lreducing substance such as hydrogen or carbon. From 5-10% by weight of carbon or equivalent reducing agent should be used. o

Pyrite may lbe converted either to FeqSs or to Fe304, both of which are highly magnetic. The former is produced by introducing air while heating at about 400 C. Further roasting at 50W-600 C.. with limited air and an atmosphere of CO, H2, and SO2 results in conversion to F8304. i

Manganese and chromium ores can be improved mage, netically by bleeding in nitrogen at the temperature of the coli.

Referring again to Fig. 4, the etliciency of the operation is greatly improved by reusing the water collected below cooling drum 133 in a sump 144. Thiscan be done by pumping it by way of a conduit 146 through a preheater 147 to the slurry tank 115 and/or heater tube 119. Alternatively, the water from sump 144 can be passed to receptacle 141 to form -a slurry with the middling, and 4this slurry can be pumped by way of a conduit 148' through a preheater 150 to the slurry ltank 115 and/or heater tube 119. Preheaters 147 and 150 are supplied with heating stearn by connection to the conduit 129 which carries the o steam from cyclone separat-or 127.

Example Ill Referring to Fig. 4, a 58% by weight water slurry of -14 mesh zinc ore containing 35% franklinite along with non-magnetic minerals is passed at a rate of 1884 pounds per hour through 800 feet of 1/2 inch heater pipe, as in Example I, to a convergent-divergent nozzle 123 having a 1A; inch throat, and thence to a cyclone separator 127 wherein steam passes olf the top and substantially dry fine oreV (-200 mesh) leaves at the bottom.

The pressures in pounds per square inch'are 1073 at the entrance to the heater pipe, 596 at the nozzle inlet, and substantially atmospheric at the cyclone. The temperature at the nozzle is 759 F. Supersonic velocity is reached in the nozzle.

The dry hot ore from cyclone 127 passes through cooler 133 wherein its temperature is reduced to about F., and into hopper 135 from which it is fed onto a magneticseparator surface 137. Franklinite is concentrated under the influence of the magnet, and the balance of the ore passes off as middling, which may be discarded or recycled, as desired. ergized at 12.5 volts with a current of 14.0 amperes.

Referring to Fig. 5, an arrangement of apparatus for performing a wet magnetic separation by my novel method is shown. :A slurry is made up in tank 149, passes through a heater tube 151 to which a suitable gas may 'be supplied through a conduit 153, as described in con-` V7 nectionwith Fig.,4, Land then. theresulting dispersion enters an opposed nozzle grinder 155 of the type described in connection with Figs.,1 and v2.

The dispersion of extremely 'ine particles of ore in steam then enters a condenser 157 wherein it is converted back to a hot slurry which is 'transferred by a conduit 159 onto the `surface of an inclined clockwise rotating belt 161. The top of belt 161 passes in close proximity to an elongated magnet 163. Suitable wet magnetic separators are described inthe `aforementioned Taggart volume, t

pages 13-19 to 13-32.

As the belt 161 revolves the magnetic particles o-f ore are carried over the top and discharged at 165 as the concentrate, while the non-magnetic particles fow. E the. bottom at 171 with the slurry Water. Meanwhile, condenser water from 157 ows by way of a conduit 1167 to a header 169 having a plurality of discharge nozzles arranged across the width of belt 161 for delivering a plurality of streams of water von the belt to.help wash the non-magnetic material to the bottom.

Non-magnetic middling particles from the bottom of belt 161 enter a receptacle 173 along with the water, and the resulting slurry .is pumped through a conduit 175 back to slurry tank 149 for further grinding along with fresh ore .to liberate magnetic material from associated gangue and prepare it for magnetic separation as described above.

Example I V Referring to Fig. a 66% by weight slurry of -14 mesh taconite iron ore in water is passed at a rate of 2307 pounds per hour through 1000 feet of 1/2 inch heater pipe 151, as in Example I, to an opposed jet grinder 155 having FAG inch LD. nozzles, and thence to a condenser 157 wherein a slurry is reformed wherein the particles are substantially all 200 mesh.

'.Ihe pressures in pounds per square inch are 1642 at the entrance to the heater pipe, 1224 at the nozzle inlets, and substantially atmospheric at the condenser. The temperature at the nozzle inlets is 751 F. Sonic velocity is reached in the nozzles, but the velocity upstream is not more than 100 feet per second to avoid erosion.

The -200 mesh ground taconite ore slurry passes onto belt 161 for separation of the m'agnetitev (which passes `olf the top) from the siliceous gangue (which ilows down and passes off the bottom.)

Many different ores are amenable to magnetic concentration by my novel method, the principal ones being those containing the iron mineral magnetite. For example, the iron content of taconite, consisting predominantly of silica combined with a relatively small amount of magnetite, can be readily separated. Other separations which can be accomplished in this way are roasted hematite and limonite from silica; roasted siderite from siliceous and carbonaceous gangue; roasted pyrite from blende unaltered in the roasting; pyrrhotite from blende, and from quartz and basic silicates. Other commercial separations are: franklinite from Willemite, zincite, and calcite; pyrolusite and psilomelane from siliceous gangue and limonite; chromite from silicates; rutile from apatite; copper carbonates from siliceous gangue; wolframite from cassiterite; magnetite and ilmenite from monazite sands; ilmenite from cassiterite concentrate; rutile, brookite, and ilmenite from orthoclase feldspar; and wolframite from a tungsten-bismuth concentrate.

Obviously, many modifications and variations of the invention, as hereinbefore set forth, may be made without departing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated in the appended claims.

The embodiments of the invention in which an exclusive property or privilege is claimed are dened as follows:

1. A method of producing a finely-divided mineral concentrate from a mass of relatively coarse particles of an ore which contains said mineral associated withvother bulent flow to-cause said particles to impinge against one another and disintegrate'to relatively iine particles, some of said ne particles being rich and others poor in said mineral; atleast partially condensing said steam and forming a owable mixture of said tine particles in the resulting water; and then separating said rich particles from said poor particles in said flowable mixture and collecting said rich particles to form said concentrate.

2. A method in accordance with claim 1, wherein there is a substantial diierence between the magnetic attractabilities of said mineral and said material, and wherein separating said rich particles from said poor particles is accomplished by subjecting said particles to a magnetic field.

3. A` method in accordance with claim 1, also comprising maintaining in contact with said ore during said heating step an atmosphere of a gas which promotes the magnetic attractability of a constituent of said ore, thereby assuring a substantial difference between the magnetic attractabilities of said mineral and said material; and wherein separation is accomplished by subjecting said particles to a magnetic field.

4. A method of producing a timely-divided mineral concentrate from a mass .of relatively coarse particles of an ore which contains said mineral associated with other material, said method comprising forming a flowable mixture of said particles in a vaporizable liquid; passing said mixture into an initial portion of an elongated iluid conduit; heating said mixture in said fluid conduit to vaporize liquid and form a dispersion of said particles in hot vapor; passing said dispersion through a latter portion of said fiuid conduit at high velocity in turbulent flow to cause said particles to impinge against one another and disintegrate to relatively tine particles, some of said tine particles being rich and others poor in said mineral; separating vapor from the iine particles of ore to provide a substantially dry ore; passing said dry ore to a magnetic separator; and separating said rich particles from said poor particles by subjecting said particles to a magnetic field in said magnetic separator. j

5. A method of producing a finely-divided mineral concentrate from a mass of relatively coarse particles of an ore which contains said mineral associated with other material, said method comprising forming a owable mixture of said particles in a vaporizable liquid; passing said mixture into an initial portion of an elongated fluid conduit; heating said mixture in said fluid conduit to vaporize said liquid and form a dispersion of said particles in hot vapor; passing said dispersion through a latter portion of said uid conduit at high velocity in turbulent flow to cause said particles to impinge against one another and disintegrate to relatively fine particles, some of said fine particles being rich and others poor in said mineral; separating hot vapor from the fine particles of ore to provide a substantially dry ore; cooling said ore; passing said dry ore in a relatively cool condition to a magnetic separator; and separating said rich particles from said poor particles by subjecting said tine particles to a magnetic field in said magnetic separator.

6. A method in accordance with claim 5, wherein cooling of said ore is accomplished by passing a owing body of said vaporizable liquid in indirect heat exchange relationship therewith, said method comprising the additional step of passing said vaporizable liquid thereafter into mixture with said relatively coarse particles for forming said slurry.` Y

k7. A method in accordance with claim 6also comprising passing said separated hot vapor in heat exchange relationship with said vaporizable liquid after fcooling said ore therewith to preheat said vaporizable liquid prior to forming said slurry therewith.

rEl. A method of producing a finely-divided mineral concentrate from a mass of relatively coarse particles of an ore which contains said mineral associated with other material, said method comprising forming a owable mixtures of said particles in water; passing said mixture into an initial portion of an elongated iluid conduit; heating said mixture in said fluid conduit to vaporize liquid and form'a dispersion of said particles in hot vapor; passing said dispersion through a latter portion of said fluid conduit at high velocity in turbulent flow to cause said particles to impinge against one another and disintegrate to relatively ine particles, some of said line particles being rich and others poor in said mineral; condensing vapor in said dispersion to form a new fiowable mixture of said fine particles by passing a cooling liquid in heat exchange relation therewith; passing said new mixture to a magnetic separator; separating said rich particles from said poor particles in said owable mixture by subjecting said fine particles to a magnetic field; passing said cooling liquid from said 'condensing step to said magnetic separator and washing therewith the material on said sepl arator to assist the separation of rich and poor particles from one another.

9. A method in accordance with claim 1 wherein said rich and poor particles are separated from one another by dotation.

10. A method of producing a nely-divided mineral concentrate from a mass of relatively coarse particles of an ore which contains said mineral associated with other material, said method comprising forming a flowable mixture of said particles in Water; passing said mixture into an initial portion of an elongated uid conduit; heating said mixture in said uid conduit to vaporize water and form a dispersion of said particles in steam; passing said dispersion through a latter portion of said fluid conduit at high velocity in turbulent flow to cause said particles to impinge against one another and disintegrate to relatively ne particles, some` of said fine particles being rich and others poor in said mineral; condensing steam in said dispersion to form a new owable mixture of said tine particles; passing said new mixture to a dotation separator; and separating said rich and poor particles from one another by flotation.

1l. A method of producing a finely-divided mineral concentrate from a mass of relatively coarse particles of an ore which contains said mineral associated with other material, said method comprising forming a owable mixture of said particles in a vaporizable liquid; passing said mixture into an initial portion of an elongated fluid conduit; heating said mixture in said fluid conduit to, vaporize liquid and form a dispersion of said particles in hot vapor; passing said dispersion through a latter portionof said fluid conduit at high velocity in turbulent ow to lcause said particles to impinge against one another and disintegrate to relatively fine particles; some of said ne particles being rich and others poorin said mineral; separating vapor from said dispersion; passing said ne particles to a flotation separator containing a pulp of such fine particles in a liquid; and passing said vapor into said ilotation separator for agitating said pulp to effect separation of said rich and poor particles from one another.

12. A method in accordance with claim `11, also comprising aspirating air with said vapor, and passing both said air and said vapor into said separator for agitating said pulp.

13. A method in accordance with claim 11, also cornprisingfcondensing part of the vapor of said dispersion,

and passing the condensed vapor with said ne particlesA to said otation separator.

14. A method in accordance with claim- 13 wherein said part of said vapors is condensed by passing water in indirect heat exchange relationship therewith, said method also comprising passing said water thereafter to said flotation separator with said condensed vapor andi said ne particles to make up said pulp.

15. A method of producing a nely-divided mineral concentrate from a mass of relatively coarse particles of an ore which contains said mineral associated with other material, said method comprising forming a flowable mixture of said particles in a vaporizable liquid; passing said mixture into an initial portion of an elongated iiuid conduit; heating said mixture in said fluid conduit to vaporize said liquid and form a dispersion of said particles in hot vapor; passing said dispersion through a latter portion of said fluid conduit at high velocity in turbulent ow to cause said particles to impinge against one another and disintegrate to relatively ne particles, some of said ne particles being rich and others poor in said mineral; passing said dispersion into a pool of pulp in a dotation separator to add said fine particles thereto while agitating said pulp with said vapor; and separating said rich particles from said poor particles in said separator and collecting said rich particles to form said concentrated 16. Apparatus for producing a finely-divided mineralv concentrate from a mass of relatively coarse particles of an ore which contains said mineral associated with other material, said apparatus comprising a slurry tank; an`

elongated iluid conduit connected to said slurry tank, said fluid conduit comprising an initial portion to receive slurry, and a latter portion for carrying a dispersion of ore in vapor at high velocity in turbulent flow to cause said.`

particles to impinge against one another and disintegrate to relatively iine particles, some of said fine particles being rich and others poor in said mineral; a condenser connected to said iiuid conduit for condensing said dispersion to a slurry; and a magnetic separator in position for receiving slurry from said condenser for separating said rich and poor particles from one another.

17. Apparatus for producing a finely-divided mineralI to relatively fine particles, some of said fine particles being rich and others poor in said mineral; a condenser connected to said fluid conduit for condensing said dispersion of a slurry, and a floatation separator connected to said condenser for separating said rich and poor particles from one another by selective flotation.

18. A method of producing a finely divided mineral concentrate from a mass of relatively coarse particles of an ore which contains said mineral associated with other material, said method comprising forming a owable mixture of said particles in water; passing said mixture into a confined heating zone; heating said mixture in said zone sufiiciently to vaporize said water thereby forming therein a dispersion of said particles in steam; disintegrating said particles of ore to relatively tine particles by passing said dispersion through a succeeding Zone of highy Velocity ow and subjecting the ilowing stream therein to turbulence and a high velocity, some of said fine particles being rich and others poor in said mineral; at least partially condensing said steam and forming a ilowable mixture of said ne particles in the resulting water; and then separating said rich particles from said poor particles in said ilowable mixture and collecting said rich particles to form said concentrate.

19. A method in accordance with claim 18 wherein said dispersion is passed at high velocity in turbulent owby discharging said dispersion in at least two mutually* opposed and impingingjets. v t

20. Apparatus for producing a mineral concentrate from a mass of relatively coarse particles of an ore which contains said mineral associated with other material, said apparatus comprising rst means -for forming a mixture of ore particles with liquid; a fiuidconduit connected to said means, said uid conduit comprising an initial portion to receive such mixture, and a latter portion for carrying a dispersion of ore in vapor at high velocity in turbulent ow to cause said particles to impinge against one another and disintegrate to relatively tine particles, some of said tine particles being rich and others poor in said mineral; second means for bringing a heating medium into heat exchange relationship with said mixture in said conduit to vaporize said liquid and form said dispersion; a condenser connected to said iluid conduit for condensingy said dispersion to reform a owable mixture of ore particles in liquid; and a separating device in position for receiving mixture from said condenser for separating said rich and said poor particles from one another.

21. Apparatus for producing a mineral concentrate from a-mass of relatively coarse particles of an ore which c ontains said mineral associated with other material, said apparatus comprising rst means for forming a mixture of ore particles with liquid; a fluid conduit connected to said first means, said uid conduit comprising an initial portion to receive such mixture, and a latter portion for carrying a dispersion of ore in vapor at high Velocity in turbulent flow to cause said particles to impinge against one another and disintegrate to relatively fine particles, some of said ne particles being rich and others poor in said mineral; second means for bringing a heating medium into heat exchange relationship with said mixture in said conduit to vaporize said liquid and form said dispersion; third means connected to said uid conduit for separating vapor from said fine particles; a oatation separator in position to receive tine particles from said third means for separating said rich and poor particles from one another by selective oatation, said oatation separator containing a pool of liquid; and conduit means connecting said third means to said Alioatation separator for conducting vapor from said third means to said separator for introduction into said pool of liquid to agitate said pool.

22. Apparatus for producing a mineral concentrate from a mass of relatively coarse particles of an ore which contains said mineral associated with other material, said apparatus comprising iirst means for forming a mixture of ore particles with liquid; a uid conduit connected to said iirst means, said fluid conduit comprising an initial portion to receive such mixture, and a latter portion for carrying a dispersion of ore in vapor at high velocity in turbulent flow to cause said particles to impinge against one another and disintegrate to relatively ne particles, some of said line particles being rich and others poor in said mineral; second means for bringing a heating medium into heat exchange relationship with said mixture in said conduit to vaporize said liquid and form said dispersion; a oatation separator comprising a tank having a pool of liquid therein; and conduit means connecting said latter portion of said fluid conduit to said floatation separator to conduct said dispersion into said pool of liquid below the surface thereof for simultaneously introducing tine ore particles and agitating said pool of liquid, to elect separation of rich and poor particles from one another by selective iloatation.

23g Apparatus for producing a mineral concentrate from a mass of relatively coarse particles of an ore which contains said mineral associated with other material, said apparatus comprising iirst means for forming a mixture of ore particles with liquid; a uid conduit connected to said `first means, said fluid conduit comprising an initial portion to receive such mixture, and a latter portion for carrying a dispersion of ore in vapor at high velocity in. turbulent 110W t0 .Cause Said particles t0 impnge against Otis @ether and disintegrate to relatively flue Particles, some of said tine particles being rich and others poor in said mineral; second means for ybringing a heating medium into heat exchange relationship with said mixture in said conduit to vaporize said liquid .and form said dispersion; third means connected Ato said fluid conduit for separating hot vapor from said dispersion; an ore cooling device connected to said separator for receiving iine ore particles therefrom, said device including means for passing cooling liquid in heat exchange relationship with said ore particles, and means for collecting used liquid; a separator `in position for receiving ore particles from said cooler for separating said rich and said poor particles from one another; conduit means for conducting liquid from said pool back to a fore part of said apparatus; and means for passing said hot vapor from said third means in heat exchange relationship with said last named liquid for preheating said liquid.

24. A method of producing a finely-divided mineral concentrate from a mass of relatively coarse particles of an ore which contains vsaid mineral associated with other material, said method comprising forming a flowable mixture of said particles in a vaporizable liquid; passing said mixture into an initial portion of an elongated fluid conduit; heating said mixture in said fluid conduit to vaporize liquid and form a dispersion of said particles in hot vapor; passing said dispersion through a latter portion of said uid conduit at high velocity in turbulent flow to cause said particles to impinge against one another and disintegrate to relatively tine particles, some of said ne particles being rich and others poor in said mineral; condensing vapor in said dispersion to form a new flowable mixture of said iine particles by passing cooling liquid in heat exchange relation therewith; thereafter passing said cooling liquid into said new ilowable mixture to increase the liquid content thereof; passing said new flowable mixture to a floatation separator; and separating said rich and poor particles from one another by floatation.

25. Apparatus for producing a finely-divided mineral concentrate from a mass of relatively coarse particles of an ore which contains said mineral associated with other material, said apparatus comprising a tank; an elongated uid conduit connected to said tank, said uid conduit comprising an initial portion to receive a owable mixture, and a latter portion for carrying a dispersion of ore in vapor at high velocity in turbulent iow to cause said particles to impinge against one another and disintegrate to relatively line particles, `some of said fine particles being rich and others poor in said mineral; a condenser connected to said uid conduit for condensing said dispersion to a flowable mixture; and a magnetic separator in position for receiving owable mixture from said condensor for separating said rich and poor particles from one another; and conduit means for conducting used cooling water from said condenser to a position adjacent said magnetic separator and for discharging said liquid onto said separator.

References Cited in the le of this patent UNITED STATES PATENTS 2,428,228 Keck Sept. 30, 1947 2,572,061 Sellers Oct. 23, 1951 2,612,320 Croft Sept. 30, 1952 2,726,813 Asdell Dec. 13, 1955 2,763,434 Strasser Sept. 16, 1956 FOREIGN PATENTS 683,318 Great Britain Nov. 26, 1952 OTHER REFERENCES Handbook of Mineral Dressing by Arthur F. Taggart, published by John I. Wiley and Sons, Incorporated, copyright 1945, pages 12-1 to 12-47; pages 13-15 to 13-19 and pages 13-19 to 13-34.

Claims (1)

1. A METHOD OF PRODUCING A FINELY-DIVIDED MINERAL CONCENTRATE FROM A MASS OF RELATIVELY COARSE PARTICLES OF AN ORE WHICH CONTAINS SAID MINERAL ASSOCIATED WITH OTHER MATERIAL, SAID METHOD COMPRISING FORMING A FLOWABLE MIXTURE OF SAID PARTICLES IN WATER; HEATING SAID MIXTURE TO VAPORIZE WATER AND FORM A DIPERSION OF SAID PARTICLES IN STEAM; PASSING SAID DISPERSION AT HIGH VELOCITY IN TURBUTLENT FLOW TO CAUSE SAID PARTICLES TO IMPINGE AGAINST ONE ANOTHER AND DISINTEGRATE TO RELATIVELY FINE PARTICLES, SOME OF SAID FINE PARTICLES BEING RICH AND OTHERS POOR IN SAID MINERAL; AT LEAST PARTIALLY CONDENSING SAID STEAM AND FORMING A FLOWABLE MIXTURE OF SAID FINE PARTICLES IN THE RESULTING WATER; AND THEN SEPARATING SAID RICH PARTICLES FROM SAID POOR PARTICLES IN SAID FLOWABLE MIXTURE AND COLLECTING SAID RICH PARTICLES TO FORM SAID CONCENTRATE.

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