DE1912306A1 - Process for the preparation of mineral fines by flotation - Google Patents

Description

DR. ELISABETH JUNG, DR. VOLKER VOSSIUS, DiPL.-lNG. GERHARD COLDEWEY

PATENT Attorneys 1 Q 1 O * 5 Ω R

8 MÖNCHEN 23 ■ S I E G ES S T HASSE 26 - TELEPHONE 345067 - TELEGRAM ADDRESS: INVENT / M D NCHEN

uZ: E 156 (BeAo) ^{1 J} - ^M ^ · 1389

HLP 9437

ENGLISH CLAYS LOVERING POCHIH L CO., LSD. St Handles Cornwall, UK

"Process for the preparation of mineral contaminants by

Flotation "

Priority: 11th Harz 1968, Great Britain, He. 11 .856 / 68

The invention relates to a method for processing mineral Embarrassment from flotation. Mineral pollutants are minerals that are practical made entirely of particles corresponding to a spherical diameter consist of less than 150 / u.

909841/0991.

It is known to separate impurities from minerals by to make a slurry of föinerals, conditioned the slurry and the conditioned slurry, subjected to a flotation process. In general a collector is added to the mineral slurry insulation in such a treatment process »2.3. a long chain Fatty acids like oleic acid, or an aliphatic anine with 8 to 20 carbon atoms, the slurry is conditioned by stirring in one! thanks to the conditioning is carried out so long that the slurry is supplied with an energy of up to about 3.7 kV / h per ton of solid substance and in that air is subsequently passed in a known manner through the slurry in a flotation cell, wherein the impurities are separated from the mineral. In most cases, the flotation process is used with the Slurry carried out at alkaline pH values. It can it may be advantageous to use an alkaline substance, e.g. amnonium hydroxide, to be added to the slurry prior to conditioning to ensure that the pH levels are optimal Conditions. It is also known to use a foaming agent such as turpentine oil for conditioned slurry before the flotation is carried out.

In some cases and especially when processing mineral fines, however, it is found that the selectivity that is achieved with known flotation processes, is small and the proportion of the impurities removed

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is on the order of $ 50 or less. In addition, some minerals contain ₉ e.g. clays? naturally a high proportion of more than 40 wt .- $ particles of extremely small dimensions, corresponding to a spherical diameter of 2 / u or less Clumping together and flaking minerals in great hatreds, the impurities being trapped and retained in the agglutinated masses. In many flotation processes that are used on an industrial scale, the material consisting of particles below 50 / rev, which is obtained in the form of a slime, is separated from the raw material and discarded. In order to overcome these difficulties, it has already been proposed to deflocculate the mineral fines, for example by adding a dispersing agent such as sodium silicate to the slurry before the slurry is flotated. It has also been suggested that an activator, such as a water soluble salt of an alkaline earth metal, be added to the slurry prior to performing the flotation process. As a result, completely satisfactory results are still not obtained in the case of the slime that is produced. Recent attempts to make such substances usable have resulted in the use of particulate auxiliary substances as carriers which effectively increase the size of the minerals. Procedures of this type are z.3. described in the US-Patentnchriften 2,990,950 and 3,224,562. These

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However, procedures have the disadvantage that they reduce the cost of Significantly increase the produleceand, in general, a separation the required minerals from the particles of the excipients.

The state-of-the-art flotation processes have already been carried out with different types of flotation cells. A frequently used flotation cell is provided with a centrally arranged agitator, in which the agitator is in the slurry dives and with peripheral speeds of up to about 6.35 m / sec. is operated.

It has been found that the difficulties in processing clays and other mineral fines, and particularly minerals which are natural mucilages, by flotation are at least partially due to a threshold of potential energy which the entry of a mineral particle in the liquid phase of an aerated Prevents slurry in the boundary layer between liquid and air. In order to overcome this difficulty, the invention proposes to carry out the flotation process under conditions which ensure that the energy threshold between a particle and an air bubble is penetrated. The method according to the invention for separating mineral fines from mineral impurities by conditioning the otine and lisohen fines in an aqueous slurry which contains a deflocculant,

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Missing a collector with the slurry before or during conditioning and flotation of the conditioned Slurry in a flotation cell kit with a centrally located agitator immersed in the slurry is thereby characterized in that the agitator operates at a peripheral speed of the stirrer3 of at least 10 m / sec. operated will.

The peripheral speed of the stirrer is preferably at least 12.7 m / sec, but preferably does not exceed it 15.2 m / sec.

The method according to the invention can be used advantageously for the preparation of mineral fines, which is practical consist entirely of 3 parts, the spherical diameter of which is less than 150 / U. The procedure is special useful for the preparation of slimes, i.e. mineral fines that are practically completely illuminated by below 50 / u and in particular of minerals such as Kaolinites containing more than 40 weight-ji particles of a size below 2 / u included.

As is the case with the known methods, can According to the invention, it may be advantageous to mix the aqueous slurry of the minerals with an alkaline before or after the Konditlonierett Substance to increase the pH-words'a d ei * aqueous slurry to an alkaline range, · a.B. about a pH

Value 9 »and to be mixed with an activator. In addition, in most cases, if not always »advantageous, add a foaming agent to the conditioned mineral insulation before the flotation process is carried out.

The process according to the invention has, as has been found, a special value in the preparation of kaolinite clays, but can also be used for the preparation of other clays and for the separation of smaller amounts of, for example, silica-containing minerals such as gypsum, gelestite, barite , Calcite, dolomite, fluorspar and phosphate arisen, e.g. apatite, are used. Many of these minerals consist of particles larger than 50 Ai in size immediately after degradation, but it is often advantageous to grind the minerals until they consist mainly of particles less than 50 microns, as this will allow better release of the contaminants will. In the previously used flotation processes, the presence of particles below 50 / rev was undesirable for the reasons already mentioned. However, the method according to the invention allows a feed to be processed in a more finely divided manner. .. - .-

The conditioning in the method according to the invention is preferably carried out under conditions that allow a thorough Ensure that the mineral particles are washed out. In particular . does the conditioning at one level of the aqueous mineral slurry of solid substance of at least 30% by weight "/ * so

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long performed that the slurry was at least 18.6 kV / h Energy per sun absorbs solids. These conditions differ considerably from those commonly used Conditioning conditions in which that of the slurry Supplied energy seldom more than 3.7 kWh per sun Minerals exceeds · Preferably according to the invention the Conditioning with a pesticide content of 40 to 60 wt. Ji carried out·

In order to carry out the flotation process, the is conditioned te clay slurry containing the foaming agent, introduced into the flotation cell, which is arranged with a centrally located Agitator is provided, the agitator being immersed in the slurry. A suitable type of flotation cell is im "Handbook of Mineral Dressing-Ores and Industrial Minerals" by iaggart, pages 12-64. However, the cell should be modified in such a way that the stirrer with the invention can be operated at substantial high speed.

A suitable flotation cell is attached in Figure 1 of the Drawings reproduced. According to FIG. 1, the cell consists of a stirrer 1 operated by an electric motor 2 which is fixed on steel girders 3 · Dar drive takes place through an arrangement of belts and pulleys on a vertical axis 5 »which can be rotated in a bearing 6 is arranged. The stirrer 1 is surrounded by hood 7, the

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is supported by four diagonal impact walls 8. The axis 5 is surrounded by a cladding 9 which is connected to the hood 7 and the baffle walls 6. The conditioned slurry is fed through a pipe 10 which feeds the slurry into the interior of the casing 9. The hood 7 has a shaft of openings so that the slurry can be drawn off by the stirrer through the openings. The casing 9 also has holes 19 'through which the slurry can circulate through the casing 9. At the same time, air from the stirrer 1 is introduced into the cell through the upper opening of the casing 9. The pulp generated in the device runs through an opening 11 over an overflow 12 from the cell _9, whereby the height of the overflow 12 can be adjusted by adding or removing wooden strips which are arranged in slots at each end. The pulp drained from the device leaves the cell through an opening 13. The fill level of the conditioned slurry in the cell during flotation is indicated at H, the foam surface being 15 , which is driven by a suitable drive from the Hotor 2. The cell walls 18 are made of wood.

According to the invention it is essential that the peripheral speed of the stirrer is at least 10 n / sec ₀ so that a particle is given a sufficient pulse by impact,

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that it is the energy threshold between the particle and a Can break through the air bubble. The lowest mentioned peripheral speed for the stirrer is generally sufficient that the ventilation volume of the cell is at least 600 liters of air each However, each cell volume is It is advantageous if the ventilation is also set to at least 800 liters Air per minute per m cell volume is increased.

Although good separation of the mineral impurities from the raw mineral by working in batches in one Flotation cell can be achieved is the separation of larger amounts of impurities by continuously working and connecting a number of similar flotation cells !! possible in series. Here, the pulp drained from the first flotation cell is brought into a second flotation cell, where further impurities are removed, and this process is continued until the desired purity of the mineral is achieved.

Figure 2 of the accompanying drawings shows a flow diagram of a flotation plant which is used to carry out such a Step process is suitable · Here, for example, a clay mineral is processed in six cells of the same type 21 to 26 arranged one behind the other, each cell being operated in such a way that the peripheral speed of the stirrer is greater than 12.7 m / sec. amounts to. The product obtained from the cell 26 represents the purified end product.

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he »I yj mm

Slurry A is put into a conditioning device together with an alkaline substance B, a collector C and an activator D 20 in which the slurry is conditioned. After conditioning, a foaming agent E is the Slurry added and the resulting mixture fed into the first flotation cell 21. The effluent from cells 21 and 22 is discarded. * The outflow from the cells 23 to 26 can go back in two cleaning cells 27 and 28 to release ϊοη, which is carried over with the foam has been. The output from cell 28 is mixed with the input to cell 24 and the output is out cells 27 and 28 is discarded. You total dwell time the clay in the plant is generally in the range of 30 to 100 minutes.

The required reagents do not necessarily need to be in the required total amount for the aqueous suspension of the mixture. mineral can be added before the start of flotation. For example, when treating a xon mineral, a Collector and an activator are used, of which only half the required amount is preferably added before the start of the flotation · During the flotation, further smaller amounts of these reagents are added at intervals. The solids content of the conditioned slurry is, if necessary, 10 to 40% by weight, preferably 15 to 30 percent by weight set before the slurry is fed into the flotation cell.

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The special conditions and substances that lead to the best results lead, vary depending on the type of mineral to be processed. The preparation of various minerals according to the invention is explained in more detail below.

Clay containing kaolinite

In the treatment of clay minerals, it is advantageous to keep the mineral slurry at a high solids content for so long to condition that the energy consumption of the slurry is at least 18.6 kWh per sun of the mineral. It is essential that the conditioning be carried out on the slurry is after a deflocculant has been added, but before optionally adding a foaming agent if ο the base deflocculant can be, for example, liatric silicate, that in an amount of 0.45 to 5.4 kg. every t dry clay is lingered "

Before or during the conditioning of the aqueous clay an alkaline substance should be added to schläronamg the pH-fourth of the clay slurry to the alkaline range, preferably to a pH of 9 to increase. The alkaline compound used can be ammonium hydroxide, although also other alkaline compounds can be used. When using ammonium hydroxide are generally 0.89 to 2.23 kg per ton of dry 5) on used.

. 'The use of an activatora, which is preferably a water

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soluble SalE of an alkaline earth metal or a heavy metal is, whereby the alkaline earth metals also include magnesium and under "heavy metal" a metal with a density of more than 4 should be understood, is advantageous · As an activator, e.g. a water-soluble salt of barium, such as barium chloride, of calcium, like calcium chloride, a copper (II) ealz »a Iron II salt, a lead II salt, e.g. lead acetate and lead nitrate, a magnesia salt, a manganese salt or a salt of strontium or zinc can be used. She used Ak « tivator range is usually 89 6 to 1.12 kg per ton dry clay.

As a collector for the mineral impurities, e.g. a fatty acid with 8 to 20 carbon atoms that is saturated or is slightly unsaturated. Preferred collectors are oleic acid and xauric acid, for example generally have 675 g to 3.35 kg oleic acid per Tcteme dry clay use found.

The same applies to the processing of kaolinitic clays It is advantageous to use a foaming agent such as wood turpentine oil which is generally used in an amount of 223 g to 1.12 kg per ton of dry clay. as Foaming agents can also be a lower alkyl ether of polypropylene glycol are used, which is generally used in an amount of 134 to 890 g per ton of dry clay.

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~ 13 -

After the aqueous clay slurry has been conditioned and before it is treated in the flotation cell for the foam soaking process, it is preferably treated with water diluted to a pesticide content of 15 to 30 wt .- ^

The processing of kaolinite-containing clays according to the invention is illustrated in more detail by the following examples 1 to 5. The effectiveness of the reprocessing process is hereby made Hesse measured the brightness of the clay product, where the brightness is the percentage of power reflection at a certain wavelength. The lighter the product, the more effective it is is the procedure *

example 1

The following attempts were made with a raw one Son from Georgia, V, St.A. carried out with a brightness of 84 units, which contained 45 wt .- ^ particles below 2 / u (corresponding to the spherical diameter). The raw son contained a certain amount of titanium dioxide as an impurity. Samples of an aqueous slurry of the son of varying solids content were conditioned using a flotation cell according to Pigur 1, the air supply of which was closed, for a period of 45 minutes · Ee the following agents were added to the slurry prior to conditioning:

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Reagent Hange in kg / t of solid like ammonium hydroxide 1.84

oleic acid 1.78

Calcium chloride 1.12

sodium silicate 1.78

The slurry samples were then reduced to 16 wt. Solids content diluted and under the same conditions in processed in the same flotation cell. The cell was 15 × 2 cm * wide and the stirrer was 7.6 cm in diameter and was with an open air supply at a peripheral speed from 15.2 m / sec. operated. During the froth flotation were a further 1.12 kg oleic acid and 45 g wood turpentine oil per t solid ion added.

The brightness of the various samples according to the plot as a function of the energy consumption of the clay soles measurements were taken during conditioning. The values are listed in the following table I.

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TABELBE I

Solids content of the
Slurry, wt .- ^ p Energy absorption of the
Slurry after
45 min.
kWh / t solids Brightness of the
Product after
of flotation »
units 10 3 87.5 20th 6.73 88.1 30th 10.5 88.5 40 14.2 88.7 50 17.2 89.1 60 20.9 89.5

Ex iel __2

The Eon samples used in Example 1 were processed under the same conditions, but with a slurry 40 # solids content used and various conditioning times applied. The results are shown in Table II below, with the brightness of the products according to the flotation was measured.

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! PABBLItB IX Brightness dee
Product after
the flotation,
units 87.8 Conditioning time,
Out there Energy absorption of the
Slurry,
kWh / t solids 88.3 15 ' 5.23 88.7 30th 10.5 89.2 45 15.7 60 20.9

Example 3

An aqueous slurry of the clay used in Examples 1 and 2 was conditioned for 45 minutes, the solids content of the slurry being 50%. You energy intake the clay slurry was 22.4 kWh / tonne clay. ABsohlleSend samples were conditioned to 16 wt .- ^ Feetoffe diluted and sown in a flotation cell Figure 1 subjected to a Sohaura Sohwiana treatment «Di® flotations» ropes had a capacity of 0.7 η and the Xturehmeeeer des Rtthrera was 40.5 oxd. The samples were treated at wee & ftelndea peripheral speeds of the Eührere «BIe brightness of the end products as a function of the conformity of the Stirrer »let specified in table IXX ·

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TABBUiS III

Peripheral speed
of the stirrer, ia / sec. Ventilation, _%
1 . Air / min ./m ^p
Cell volumes Brightness of the
Product,
units 5.08
7.65
11.4
15.2 160
280
720
1 600 87.0
87.6
89.5
90.2

Be ispiel 4

A primary porcelain clay containing tourmaline with a particle size distribution of 8% by weight of particles above 10 / u diameter and 55% by weight of particles less than 2 / u diameter was mixed with water to form a 40% solids by weight slurry. Tourmaline here has a deep blue to black color and therefore a detrimental effect on the brightness of the porcelain clays in which it occurs. Afterward was used to suspend sodium silicate in an amount of about 1.78 kg / t clay was added to deflocculate the clay. The slurry was constructed in accordance with Figure 1 ' Flotation cell for the laboratory with a width of 15.2 cm with a stirrer that had a diameter of 7.6 cm, and the stirrer with a peripheral speed of

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15 i £ si / SelC added:

reagent

Ammonium hydroxide oleic acid Calcium chloride

m ^ nm <km, following ® reagent

MgHgejin j: g / tt rocker fön 0.535
0.8

0.895

The pH of the slurry was 9 »5β The slurry vnar" de in the presence of these reagents conditioned 60 Hinuten * This was the agitator of 3? Lotationazelle used, but excluding air from entering the cell, according äem conditioning, the slurry was applied to a 19% by weight of pesticides diluted. Then a slope of 272 g wood turpentine oil; per ton of dry clay was added and the cell was operated with the ventilation opening open for 30 minutes. The material washed off and the turbidity were then checked. The brightness and tourmaline content of the feed and product are given in Table IV.

TABLE IV

brightness
f » Reflection versus
Light at 574 291 Tourmaline =
salary, i * Tunaalinex-
traction,
Efficiency feed
product 458 mu 90.0
92.0 0.80
0.24 $ 70 85.5
87.0

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Example 5

Sin turaalin-containing primary porcelain clay with a particle size distribution of 25 wt .- # particles of 1s 10 / U diameter and 42 wt .- # particles of less than 2yu diameter became toit Y / ater to form a slurry at 40 Weighted solids mixed with the slicing process 445 g sodium silicate per tonne of clay added for unblocking * The slurry is placed in an abosatoriuine lotation cell similar to Figure 1, which was 15.2 cns wide and with a A stirrer of 7.6 cm diameter was equipped, the circumference of which was geeohwindiglceit 15.2 ra / Seic · was. There were the following Reagents added;

Reagent Henge in kg / t trookeaer clay

Aranonium hydroxide 1.83 Oleic acid 1.11 Calcium chloride 1.07

The pH of the slurry was 9.0. You slurry was conditioned in the presence of reagents 60 minutes "but _s was being operated the stirrer of Flotationsaelle air does not let vrctrde *. At the end of the conditioning period, the slurry was diluted to 18% hydrogen. Wood turpentine oil in a quantity of 222 g / t dry clay was used and the cell was operated with an open air supply for 30 minutes and then the washed-away ma-

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material and the turbidity checked. The brightness and the iPuriaalin content of the feed and the product are listed in Table V » given.

T ABELKB V

brightness
tfa reflection against light
at 574 m / u Tourmaline
salary, {Dunaalin-
extraction,
Effect
Degree feed
product 458 τη / α 83.5
87.5 2.8
0.5 82? P 79.5
82.0

Celestite

In the treatment of Oelestiterzen the Era is preferably characterized conditioned to be added zn a wäQrigea slurry with at least 30 wt .- # Celestiter "a collector, an oily auxiliary reagent and a dispersant and the slurry in (put waiting these substances is conditioned so long until at least 18.6 kWh of energy 3 "lonn © solids © have been absorbed by the slurry. A sulfonated petroleum hydrocarbon ζ, e.g. a green acid, which is obtained from the refining of lubricating oils, or a salt or a soap can be used as a Sassmler of such an acid

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2.23 kg / t ore and for most ores from 81 g to 1.34 kg / t Ore. The oily auxiliary can be a commercially available animal, vegetable or mineral oil be · crude oil, paraffin and Heating oils are particularly suitable. The amount needed is usually iss range from 45 g to 1.11 kg / t of ore and at the most ores between 223 g and 675 g / t of ore · The dispersant is preferably sodium silicate in an amount that usually between 450 g and 2.68 kg / t of ore. The pesticide contained in the aqueous slurry of celestite ore during the conditioning is preferably at least 40 wt .- ^. No alkaline compound needs to be added, since the sodium silicate as a salt of a weak acid and a strong base is sufficient, the aqueous slurry is very good to make weakly alkaline.

After the conditioning it becomes a conditioning a foaming agent is added, which can be, for example, a wood turpentine oil. The required amount of turpentine oil is between 22 g and 450 g / t of ore.

The conditioned aqueous slurry is then in a flotation cell under the Sohaum swimming process. thrown, the cell having a centrally located agitator has a submerged stirrer, which moves with a peripheral speed of at least 10 m / sec. can turn

The method according to the invention is based on the treatment

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of Celestite Ore illustrated by the following® Example 6.

example

A sample of A Celestite (SrSOa) from Yate, Gloucester Shire, England with a content of 3? Oen _s bisic constituents, silicon dioxide and gypsum as impurities was ground to such an extent that the particles passed through a 53 mesh sieve. The ground Brz © wurd V / ater mixed and a slurry with 40 percent "- $ Festßtoffgehalt get · To the slurry were 445 g of a collector from the base of sodium Salzee a SrdölsulfonatSj 890 g of sodium silicate and 445 S paraffins *! added per ton of ore. The sodium sulfonate was a commercial product known as "AERO PROMOTER 801". The slurry with the additives was conditioned in a tank containing a high-speed propeller stirrer for 30 minutes so that the energy consumption of the slurry was 22.1 kWh.

The conditioned slurry was diluted to 15 5 * solids content and transferred to a flotation cell, which was constructed generally according to FIG. Me had flotation cell a capacity of 710 1 · and was with a stirrer from Equipped with a diameter of 46 cm, its peripheral speed 15.2 m / sec. 44 »5-S wood turpentine oil was used as the foaming agent added per ton of ore · In this process

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23-1S12306

the natrius serves as ies s &vü'olmxli& u & za iS3is _s to make the oelastite more hydrophobic than the impurities »The oleestite is therefore enriched from the foam and extracted from it ·

A second sample B of the same Celestite resin applied to a Particle size of 53 / U had been milled after a usual plotting process enriched · In this process the ground ore became a slurry with Yfasser rented which contained 25% by weight of solids. Bs were the the same reagents were added in the same amounts to this sample and the resulting slurry in the same for 10 minutes conditioned stirred tank, the energy consumption of the slurry being 5.7 kWh / t of ore. The conditioned Slurry was diluted to 15 percent by weight and in a flotation cell with a capacity of 710 1 transferred, which was equipped with a stirrer with a diameter of 46 cm, who had a peripheral speed of 6.35 m / sec · ale Foam concentrate was added to 44.5 g of wood turpentine oil per bottle of Ers.

The enriched celestite ore in the foam was separated and collected at the end of each coarse flotation stage and a sample of, each product was chemically analyzed.

The residue of Floated Product A was then returned to the conditioning tank and added to the slurry 179 g of the sodium salt of ErdÖ! Sulfonate, 665 g of Ha-

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triuinsilicate and 224 6 liquid paraffin per sun material added. The slurry with the additives was conditioned for an additional 30 minutes. It was found that another wood · » Oil of turpentine was not required at this stage. the conditioned slurry was then transferred to the flotation cell transferred with the high speed stirrer and a second fine flotation is carried out, at the end of which the im Foam continued to separate and collect accumulated celestite.

The remainder of the floated product B was with the addition of same reagents in the same quantities as helmet-conditioned product A, whereby the conditioning time ^ e » but only 10 minutes was «The conditioned slurry was then a second Ilal in the flotation cell with treated with the stirrer at low speed and then separated and collected further enriched celestite in the foam.

In Table VI below is the percentage of silica, Ferric oxide and calcium oxide in the feed and in «the -flotated products after the" coarse floatation "and after the "fine float" specified.

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TABLE VI

material in the flotation the end Handily SiO ₂
(55) Fe ₂ O ₃
(£) CaO
Φ) feed in the foam the end Hand-held 1.2 0.49 0.9ö Coarse product
ment A in the foam the end Hand-held 0.39 0.13 0.52 Coarse product
lung B in the foam the end Treatment 0.78 0.23. 0.72 Fine product
ment A in the foam 0.12 0.04 0.25 Tormented product
lung B 0.30 0.12 0.52

Apatite

In the treatment of apatite ores, the ore is preferably conditioned by being made into an aqueous slurry with at least 30 wt. ~ # Apatite ore a collector, an oily auxiliary reagent and a dispersant are added and the slurry is conditioned in the presence of these materials is until at least 18.6 kV / h of energy per ton of solids from the Slurry have been added. The collector is preferably a fatty acid having 8 to 20 carbon atoms in the hydrocarbon chain, which is saturated or only

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is slightly unsaturated. The required collector quantity is usually between 45 g and 2.24 kg, for most ores between 223 g and 1.78 kg per sun ore. The oily auxiliary can be a commercially available animal, vegetable or mineral oil. Crude oil, paraffin and heating oil are particularly suitable. The amount required is generally between 45 g and 1.12 kg and for most eras between 223 g and 675 g per sun ore. The dispersant is preferably halosilicate, the amount of which is generally between 450 g and 2.68 kg per sun ore lies. The pesticide content of the aqueous slurry of apatite during conditioning is preferably at least 40% by weight. Usually neither an alkaline compound nor an activator is needed.

The conditioned slurry is then subjected to a foam-float preparation in a flotation cell with a centrally arranged stirrer and an immersed stirrer, the stirrer having a peripheral speed f of at least 10 m / sec. can be operated.

The application of the method according to the invention to processing of apatite ores is illustrated by the following example 7 explained in more detail.

Ex iel 7

An apatite ore was first formed by customary wedging and

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Sorting worked up and finally ground so far that the particles passed through a sieve with a mesh size of 53 / U. The finely ground material was then divided into two parts.

The first part of the vermablenen apatite ore was closed with water a slurry of 40% by weight solids content. The slurry added 445 grams of oleic acid, 890 grams of sodium silicate and 445 g of paraffin oil was added per ton of ore. The slurry with the auxiliary materials was in a tank with a high level Speed propeller conditioned for 35 minutes, with 23 kWh of energy was absorbed by the slurry. The conditioned slurry was made to contain 18 pounds of pesticides diluted and transferred to a flotation cell, its structure generally corresponded to FIG. The flotation cell had a capacity of 710 l and was equipped with a stirrer of 46 cm Diameter equipped. The peripheral speed of the stirrer was 15 »2 m / sec. In this process it was found that a foam additive was not required. The apatite was made more hydrophobic than the impurities and could therefore be recovered in the foam.

The second part of the finely ground apatite ore was mixed with water to form a slurry with a solids content of 25% by weight mixed. The same additives were added in the same amount and the mixture in the same stirred tank Conditioned for 12 minutes, with 3.74 kWh of energy from the

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slurry were added. The conditioned slurry was .- diluted ^ solids content to 18 percent by and brought a capacity of 710 1 in a flotation cell, which contained an agitator having a diameter of 46 cm, the peripheral speed was 6.35 m / sec _e, Bas enriched apatite in Foam enriched and gained.

In the following Table VII the percentage is fully phosphorus

pentoxide, ferric oxide, aluminum oxide »calcium oxide, fluorine and silica in the feed to the flotation device and in the foam from said two treatment stages specified.

TABLE VII

material P ₂ O ,. Fe 2 ° 3 Al _? 0 ^ CaO 4th F. SiO _? <*) ( ( tf) (£> 9 (<■;) (*) Feeding into the
Flotation 35, 6th 0 ,8th 1 , 4 50, 6th 2 * 53 4, 7th Ge in the usual way
won product 39 5 0 , 3 0 »9 51 * 2.84 1, 2 According to the invention ge
won product 40, 7th 0 »2 0 , 6 52, 2.97 0, 8th

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Claims (3)

P A Π? S I T A Ii S P R 0 O II E ί 1. Process for the separation of mineral fines of mineral impurities by conditioning the mineral fines in an aqueous slurry that contains a deflocculant »mixing a collector with the slurry before or during conditioning and Flotation of the conditioned slurry in a flotation cell with a centrally arranged agitator immersed in the slurry, characterized in that that the agitator with a peripheral speed of the stirrer of at least 10 m / sec. is operated· 2. The method according to claim 1, characterized in that the stirrer with a peripheral speed of at least 12 ₉ 7 m / sec. is operated· 3. The method according to claim 1 or 2 »thereby characterized in that the mineral fines in the form of an aqueous slurry with a solids content are conditioned by at least 30 wt. that the energy consumption of the slurry is at least 18.6 kWh / t solid mineral amounts. 4. The method according to claim 3, characterized in that - 909841/0991 jo <= » indicates that the mineral fines in In the form of an aqueous slurry with a solids content of 40 to 60 wt .- ^ are conditioned, 5o The method according to claim 1 to 4 _f ά..adurc hg e indicates that mineral fines are used, which consist almost entirely of particles of a size corresponding to a spherical diameter of less than 50 yu. 6. The method according to claim 1 to 5 »thereby marked« draws that one sees a kaolinite as a mineral fine substance Sound sets in. 7. The method according to claim 1 to 6, characterized in that the flotation with aeration at least 800 liters of air per minute per cell volume. 3. The method according to claim 1 to 7, characterized in that that a conditioned slurry is fed into the flotation cell, the solids content of which is 15 to 30 wt amounts to. 909841/09 91 eersers