PL166169B1 - Method of pneumogravitationally separating valuable mineral substances from particulate materilas, apparatus therefor and method of getting such substances - Google Patents

Abstract

1. A method for pneumogravitational separation of valuable mineral substances from loose material, characterized in that the loose material is delivered to the flotation chamber of the separating device, whereas that device has one at least inlet and numerous outlets, and the flotation stream can flow from one at least inlet to one at least outlet, and in that chamber, the raw material is floated by contacting the flotation stream featuring a determined air flow speed being sufficient to divide the raw material in one at least valuable mineral fraction, whereas that mineral fraction is separated from the flotation stream by the weight of the valuable mineral content, and the waste fraction remains in the flotation stream, and then, this one at least separated valuable mineral fraction gathers at one outlet of the flotation chamber, and the waste fraction gathers at another outlet of the flotation chamber.18. A device for the pneumogravitationally separating valuable mineral substances from loose material, characterized in that includes a flotation chamber (54) of an oblong shape, and in the casing (52), it has the first inlet (60) and the first outlet (70),...<IMAGE>

Description

The subject of the invention is a method of pneumogravitational separation of valuable minerals from loose material and a device for pneumogravitational separation of valuable minerals from loose materials. In particular, the invention provides a method and an apparatus for recovering substantially pure mineral substances as well as other valuable secondary raw materials from such bulk materials as fly ash, slag and the like.

So far, a number of methods and devices for the extraction and recovery of mineral resources from materials such as fly ash, slag and the like have been proposed.

For example, U.S. patents Nos. 3 1 75 900, 3 5571 533,

819 363, 3 843 351, 3 932 171, 3 945 557, 4 002 766, 4 082 832, 4 0-48 285,

225 565, 4 454 013,

2552 577, 4 4774 535,

310 050, 4 508 040,

337 900, 4 610 722.

361 4141, 4 617 180,

293 978, 4 652

410 358, 4 668 352,

783 \ (^ 7,

177 060, 7 436 5 ^ <^, 4 789 532,

Re 28 750 and British Patent Nos. 1,273,523 and 1,317,888 disclose various technical processes and devices for the extraction and recovery of a variety of mineral resources from a variety of raw material resources.

The known methods and devices, however, usually had drawbacks which prevented their economically useful use. Some processes were too energy intensive, others required the use of economically uneconomical amounts of reagents or other elements of the processes. Still other ways were too slow or too complicated. There were also some proposals that did not solve the problem of waste materials in an ecologically or economically satisfactory manner or even created additional environmental problems. For example, some of the older solutions required excessively costly and complicated gas cleaning systems and other devices to reduce environmental pollution, especially the atmosphere.

The present invention has been developed in response to the above-mentioned shortcomings of the prior art.

The general object of the invention is to improve methods of isolating substantially pure mineral fractions such as alumina and titanium oxide from mineral-containing raw materials, preferably from waste raw materials such as fly ash, furnace dust, slag, waste from foundry and other metallurgical processes. mine tailings, sea sand and the like.

It is also an object of the invention to provide an economically viable environmentally beneficial and commercially viable technology for the isolation of substantially pure mineral fractions.

It is a further object of the invention to provide commercially viable methods for isolating byproducts in addition to substantially pure mineral fractions, preferably from waste materials such as fly ash, furnace dust, slag, waste from foundry and other metallurgical processes, mine tailings, sea sand and the like.

166 169

A still further object of the invention is to provide a method of recovering alumina, titanium oxide, iron, chromium, nickel, cobalt, lead, zinc, copper, zirconium and other valuable elements and other valuable by-products from waste materials from foundries, power plants, landfills, processes aimed at reducing environmental pollution, such as, for example, from works on cleaning the seabed and similar sources, in such a way as to eliminate environmental problems caused by the exploitation of raw materials, and so that no additional problems related to the protection of the natural environment arise as a result of the use of the present invention .

More specifically, the object of the invention is to provide a one-stage method of extracting valuable mineral substances from loose materials containing minerals by the pneumatic-gravity method in a device for carrying out such a method, the invention being aimed at using the obtained materials directly or subjecting them to further treatment not being the subject of the present invention. invention, wherein the present invention is a first step.

The invention provides an economically advantageous, highly cost-effective and environmentally beneficial method and apparatus for treating loose mineral waste in order to obtain substantially pure raw materials therefrom. In addition to extracting valuable mineral content from bulk materials, the methods of the invention also provide the recovery and recovery of commercially valuable by-products with significant utility, for use as e.g. building materials, binder fillers, and the like. The method covered by the invention ensures the utilization of all loose raw materials with significant environmental benefits.

Depending on the type of raw material to be processed, its composition, the desired degree of purity of the final product and other variables to be assessed in each case, the present invention is suitable for single-phase or multi-phase processes (further phases are not included in the present invention). A multiphase process, preferably a two-stage process, uses or only one of the physical and chemical separation methods to achieve the desired extraction rate and recovery of the mineral content from the raw material and to recover other valuable by-products from the remainder of the procedure.

The method of pneumogravitational separation of valuable minerals from a mineral-containing bulk material according to the invention consists in that the mineral-containing bulk material is introduced into the flotage chamber of the pneumogravity screening device having at least one inlet and a plurality of outlets through which the flotation stream can flow from at least one inlet to at least one outlet, this feedstock is flotated by contacting it with a flotation stream at a predetermined air flow velocity sufficient to cause the feed to separate into at least one valuable mineral fraction which precipitates from the flotation stream by the gravitational fall of this fraction from the stream under the weight of a valuable mineral substance and onto the waste fraction remaining in the flotation stream, and the at least one precipitated valuable mineral fraction is collected for one one of the listed flotage chamber outlets, and the remaining waste fraction at the other outlets.

According to the invention, preferably the mineral-containing bulk material is moistened with a sulfuric acid solution before being introduced into the flotage chamber.

Preferably, the flow rate of the flotation stream is kept in the range of 2 to 25 m / s.

Preferably, the treated bulk material has a grain radius smaller than about 0.1 mm.

Preferably, a free-flowing material obtained by crushing a solid material containing minerals is treated.

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Preferably, a material selected from the group consisting of: fly ash, furnace dust, slag, coal, foundry and metallurgical waste, mine tailings, sea sand and mixtures thereof is treated.

Preferably, the foundry scrap is a slag produced by the iron-chromium production process. It is also preferred to use fly ash produced from blast furnace slag.

Preferably, the bulk material is treated with a sulfuric acid solution prior to entering the flotage cell.

Preferably, in the process according to the invention, a fraction belonging to the group consisting of: alumina, titanium oxide, iron, chromium, nickel, cobalt, lead, zinc, copper, zircon and mixtures thereof is collected as a valuable mineral, and the collected waste fraction is subjected to further processed to produce a building material with the characteristics of cement.

In particular, the method of extracting mineral substances from a mineral-containing bulk material according to the invention consists in that the bulk material is introduced into a pneumogravity separation device having an elongated flotation chamber with a first inlet and a first outlet, means for introducing air into the chamber through the first inlet and forcing it to flow through the chamber and leaving it through the first outlet, a second inlet for introducing the bulk material into this chamber so as to be able to contact the flotation flow, located in the flotation chamber at a sufficient distance from the first outlet to allow it to separate out at least one mineral fraction and fall from the flotation stream by gravity settling under the weight of the mineral substances contained in that fraction, and at least one such mineral fraction is collected from the device.

Preferably, in this method, the bulk material is introduced into the flotage chamber through a second inlet located at a distance from the first outlet defined by the formula:

C.

Fd ² / _C where C is the horizontal distance between the second inlet and the first outlet, C is the constant coefficient calculated on the basis of the Reynolds number, which in the case of laminar air flow through the flotation cell is 18, V is the velocity of the gas (air) flowing through the flotation cell , Mg is the dynamic viscosity of the gas, F is the cross-sectional area of the flotage chamber, d is the average diameter of the particles entering the flotage chamber, y _c is the specific gravity of the particles, and H is the chamber height.

In the method according to the invention, the bulk material is introduced into the flotage chamber through a second inlet with a structure enabling the adjustment of the feed angle of this material. Preferably, the bulk material is introduced into the flotage chamber at an angle of about 12-75 ° to the direction of the air current flowing through the chamber. Preferably, in the method according to the invention, the loose material is introduced into a device additionally equipped with a flotage chamber tilting mechanism enabling the adjustment of the angle between the horizontal direction of air flow through this chamber and the longitudinal axis of this chamber. Preferably, the angle between the horizontal direction of the flow of air current through this chamber and the longitudinal axis of this chamber is adjustable from about -60 to + 60 °.

The invention also relates to a device for the air-gravity separation of valuable minerals from mineral-containing bulk materials, which according to the invention comprises an oblong-shaped flotage chamber in a housing having a first inlet and a first outlet, means for introducing air into the chamber through the first inlet, and for forcing air into the chamber through the first inlet. air flow through the flotage chamber in the direction from the first inlet to the first outlet, providing a flotation stream of air in the chamber, flowing from the first inlet to the first outlet, and a second inlet for introducing the bulk material therein and contacting the flotation stream, the second inlet being located in the chamber at a sufficient distance from the first outlet

166 169 to allow the separation of the valuable minerals contained in the bulk material in the form of at least one valuable mineral fraction and its fallout from the flotation stream by gravity settling under the weight of the valuable minerals contained in this fraction, and a second outlet for receiving the separated mineral fraction.

Preferably, in the device according to the invention, the distance between the second inlet and the first outlet is given by a pattern.

CH V Mg

L = -3F d ² ) _c where L is the horizontal distance between the second inlet and the first outlet, C is the constant coefficient calculated on the basis of the Reynolds number, which in the case of laminar air flow through the chamber is 18, V is the gas velocity (e.g. of air) flowing through the chamber, Mg is the dynamic viscosity of the gas, F is the cross-sectional area of the chamber, d is the average diameter of the bulk particles entering the chamber through the second inlet, y _c is the specific gravity of the particles and H is the height of the chamber.

In the device of the invention, the second inlet is constructed to regulate the angle of introducing the bulk material into the chamber. Preferably, the angle [alpha] is 12-75 [deg.] To the direction of the air current flowing through the chamber.

The device according to the invention additionally has a chamber tilting mechanism for adjusting the angle β between the horizontal direction of air current flow through the chamber and the longitudinal axis of the chamber. Preferably, the angle β ranges from -60 to + 60 ° with respect to the horizontal direction of the air flow.

The structure of the flotage chamber according to the invention may have a rectangular, square, round or other cross-section suitable for the fact that only the air stream flows into the chamber through the inlet port on one side and flows through the chamber into the outlet port on the other side. The bulk material is introduced into the chamber through a separate opening located at a sufficient distance from the chamber air outlet to ensure optimal separation of minerals from the treated bulk materials.

As mentioned above, it is preferable to moisten the raw material with a sulfuric acid solution before introducing it into the device according to the invention in order to react the active particles with acid so as to increase the specific gravity of these particles and thus reduce the likelihood of these heavier particles sticking together or agglomerating inside the chamber in the chamber. during the purge. The bulk material should be introduced into the chamber at an angle of between 12 and 75 ° with respect to the axis of the laminar air flow direction from one side of the chamber to the other. The velocity of the air flow through the chamber should be kept within the range of about 2 m / s for the lighter particles up to about 25 m / s for the heaviest particles, such as lead oxide with a specific weight of about 13 g / dm ³ . It has been found that a flow velocity of less than about 2 m / s does not screen out the particles.

The device according to the invention is equipped with a chamber tilting mechanism to adjust the angle p, which allows the time and distance traveled by the particles to be selected before they enter the air stream. This angle is preferably in the range from -60 to 0 ° (in the horizontal plane), which allows the lighter particles to be absorbed, increasing the time and distance before they are entrained by the air stream, and from about +60 to about 0 ° (in the horizontal plane) to take over heavier particles by reducing these parameters.

According to the invention, the pneumogravity technique is used to obtain mineral products such as metal concentrates and their oxides from a bulk material. In other processing stages not covered by the present invention, it is possible to heat-chemically treat the raw material or to treat the end product of the pneumogravity separation with plasma in order to obtain essentially pure mineral products and precipitates.

The treatment of further by-products which may be used alone or in combination with other waste residues from the pneumogravity separation process as building materials, such as cement-like products, fillers and the like.

In a preferred embodiment of the invention, mineral containing bulk material with particles having a radius less than about 0.1 mm is introduced into a pneumogravity distributor detailed below, with a flotage chamber provided with at least one inlet and a plurality of outlets. A fan, blower or other similar device introduces air into the chamber and causes the air flotation stream to flow from the at least one inlet to the at least one outlet, and the bulk material comes into contact with the flotation air stream at a predetermined flow rate. This velocity must be sufficient for the bulk material to separate under the influence of this stream to give a fraction of the mineral raw material which then falls out of the flotation air stream.

For this purpose, the bulk material is introduced into the flotage chamber through at least one inlet located at a certain horizontal distance from the place of air supply and at a predetermined angle to the axial direction of flow of the stream through the chamber. This mineral fraction drops from the stream under the weight of the mineral raw material contained therein. in the fraction, leaving the non-precipitating granular waste fraction lifted in the flotation air stream.

This raised granular fraction is collected from the flotation stream for further processing to obtain valuable building materials, including cement-like mixtures, fillers, and the like. In a preferred embodiment of the invention, the collected waste fractions include materials such as alumina (corundum), titanium oxide, chromium and iron salts, as well as free elements and various other compounds and elemental components derived from a wide variety of starting materials that can be processed by methods such as object of the present invention. The pneumogravitational treatment according to the invention results in a significant improvement in the purity of the obtained minerals, although it is better to subject them to subsequent processing phases, either by further pneumogravity sieving or by other extraction techniques, in order to achieve an even higher degree of purity.

As a result of the pneumogravitational separation according to the invention, the falling mineral fractions are collected and preferably further processed by a method not covered by the present invention by means of a chemical-thermal treatment using a new plasma reactor, a detailed description of which is given in Patent Specification No. 165331 (Invention Application No. P- 289214). In this reactor, the mineral fraction obtained according to the present invention is subjected to plasma screening in order to achieve a higher degree of purity of the obtained minerals. As a result of this additional treatment, substantially pure mineral products are obtained from the fractions isolated in the process according to the invention.

In such a complex process for processing mineral-containing bulk materials, part of which is the process according to the invention, a separate phase - not covered by the present invention - is plasma screening. Loose mineral fractions are introduced into the reaction chamber of the plasma reactor. It is recommended that the average diameter of the treated mineral particles should not exceed 0.1 mm. A stream of plasma gas is introduced in turn into this reaction chamber. The gas is ionized to create a plasma arc in the reaction zone between the cathode and the multi-segment anode of the reactor, where it is heated to a temperature of about 10,000 ° K. The reactor is shaped and sized so that the plasma arc can quickly rotate around the multi-segment anode. The loose fractions are subjected to this movement, so that the particles must pass through the plasma in the desired helical path. Preferably, the plasma speed is desirable in excess of 15,000 rpm. and are between 15,000 and 30,000 rpm. The most preferred speed is 16,000 rpm.

A plasma reactor not covered by the present invention is constructed to produce a rotational plasma arc discharge between two stationary electrode arrays. When a sufficiently high voltage flows between the electrode pair (i.e., between the cathode and anode), an arc discharge occurs, producing a plasma. In a preferred embodiment, the anode is a multi-membered ring with each member electrically isolated from the others. Each of them is also electrically connected to the constant potential area, i.e. grounded by a pair of cylindrical coils (solenoids) arranged on both sides of the anode member at an angle of 90 °. The axis of each such coil is parallel to a line drawn from the center of the reaction chamber to the anode member connected thereto. The plasma discharge from the cathode to a given anode member, and then to the ground, charges the appropriate pair of cylindrical coils. The resulting magnetic field causes the plasma arc to rotate towards the next anode member. This process is repeated, resulting in a rapid rotation of the arc:

Further, in a plasma reactor, a coaxial cylindrical coil surrounds the edge of the reaction zone. It is coaxial with the line connecting the cathode to the anode. The coaxial coil creates a second magnetic field, which additionally accelerates the rotation of the plasma arc, transforming the angular velocity of the plasma into linear velocity along the circumference.

For the production of plasma. Different gases are used in the generator depending on the composition of the processed raw material. These include various oxidizing gases such as atmospheric air or oxygen, reducing gases such as hydrogen, and inert gases such as argon and other noble gases.

Thus, the particles as they pass through the arc are heated to temperatures above their melting point and liquefied. The plasma reactor is further shaped and sized to accommodate a cooling zone through which the liquid exits the plasma reaction zone through gradients of ever lower temperatures as the desired minerals in substantially pure elemental or compound form cool and congeal into a relatively dense powdery form. Also, the heated residues of the initially introduced particles either crystallize, in the cooling zone, in the form of relatively low-density dust, or there they evaporate in the form of gases by first subjecting them to plasma and then cooling. Moreover, the structure of the reactor includes a blow-off zone in the opposite direction into which liquid, dust and gaseous materials pass after leaving the cooling zone. In this purging zone, these materials are subjected to a reverse air current in a manner and using apparatus which will be described in detail hereinafter. After passing through such a reverse air current, the valuable condensed minerals are brought into their substantially pure free flowing form, while the remaining dust and gaseous components are removed from the end product by the counter current of air and collected separately.

As a result of additional chemical-thermal screening with the use of the plasma reactor described above, essentially pure mineral substances with a purity level exceeding 95% are separated from the raw materials so treated. Moreover, depending on their composition, the remaining dust and gaseous components separated from the collected valuable minerals can be further processed and become a source of other useful essentially pure fractions. Another possibility is to use such waste materials as valuable by-products of the process.

The invention will be discussed in more detail on the basis of the attached drawings, in which Fig. 1 shows a block diagram of the fly ash treatment process, part of which is the method according to the invention, Fig. 2 - a block diagram of the metallurgical slag processing waste after the production of iron-chromium, of which part is a process according to the process according to the invention, fig. 3 - a block diagram of a post-galvanic waste processing process, part of which is the method according to the invention, fig. 4 - a block diagram of a sea sand processing process, part of which is a method according to the invention, fig. 5 - a device for of the pneumogravitational separation according to the invention, in a sectional side view, Fig. 6 - a chemical-thermal screening device in a side view, Fig. 7 - a plasma reactor shown in Fig. 6 in a top view with a projection from the cathode to a multi-segment unit

166 169 of the anode half, and Figure 8 is a schematic detailed representation of the relative position of the cathode and multiple anode of Figure 7 with an exposed section of portions thereof.

Figures 1-4 show block diagrams of the processing of various mineral-containing bulk materials, differing in details depending on the composition of the raw material, its physical form, mineral content and other similar considerations.

The raw material treated in the process flow chart of Figure 1 is freshly produced, dry fly ash from coal combustion in a CHP plant. In this connection, it should be noted that the fresh ash used here was sufficiently soft and could be processed without being ground to a powder. However, if the ash from the reserve or build-up heap was to be used for a longer period of time - even years - it would be necessary to grind the ash used as a raw material into particles of the appropriate size in order for the treatment method used according to the present invention to produce satisfactory results.

The composition of the fly ash used for processing may vary slightly depending on the fuel. However, the main constituents of fly ash are always silicon and aluminum, with calcium, iron, titanium and magnesium among the secondary constituents. You can also expect traces of lead, mercury, silver, manganese and chromium. The fly ash usually used in the process according to the invention comprises the following compounds:

SiO ₂ 50-56% Al ₂ O3 21-28% CaO 2-4% Fe ₂ ° ³ 7-12% TiO2 M ^ / o MgO 223%

Example 1: 10 kg of dry fly ash freshly made from coal was collected during the daily operation of the CHP plant. This 1.0 kg sample had the following percentage by weight:

SiO2 515 °% Al ₂ O ₃ 26.6% CaO 2.6% ^Fe - ^O ; 113% TiO2 1.2% MgO 2.1% Other 4.7%

This sample of fly ash was introduced into the chamber of a pneumogravity separation device of the type shown in Figure 5. After being introduced into the chamber, the ash was treated with 1 liter of 5% sulfuric acid solution; the ash reacted with the acid and formed a free-flowing, high-density sulphate fraction, which favored the deposition of active particles in further stages of the process.

In the air-gravity separation device, the particles came into contact with a laminar flotation air stream flowing through the chamber from an inlet on one side to an outlet on the other side of the chamber. The air velocity was 2 m / s, and as the particles were blown through the chamber, the heavier grains, including Al ₂ 03 and TiO ₂ , fell from the flotation stream by gravity settling, while the lighter particles remained essentially suspended in the flotation stream. The loose mineral fraction, precipitated from the flotation stream, weighed 3.08 kg and had the following composition expressed as a percentage by weight:

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Al ₂ O ₃ 68.18% Al ₂ (SO4) ₃ 9.70% SiO2 11.37% TiO2 3.89% ^F e ₂ ° ₃ 3.20% Fe ₂ (SO ₄ ) 3 1.60% MgO and MgSO ₄ 0.138% CaO 1.68% This precipitated dust fraction was collected and transferred to further processing at the stage chemical-thermal screening for mining from the product of the pneumogravit machining phase- higher purity mineral substances. The particles that remained in the flotation stream were collected separately. They weighed 6.92 kg. The percentage composition of this waste fraction, expressed as percentage by weight, was following: Al ₂ O3 2.80% Al ₂ (SO ₄ ) 3 0.87% SiO2 66 .0% ^F eA 13 ^ 2 ^% Fe ₂ (SO ₄ ) 3 1.5% CaO 3.00% TiO2 - MgO and MgSO ₄ 2 ^ 9% Other 6.788%

This waste fraction also turned out to be a valuable by-product of the method according to the invention, suitable for further processing for use in the production of cement-like building mixes and excellent quality binders and fillers.

In the chemical-thermal screening stage, the loose fraction precipitated in the pneumogravitational separation process according to the invention was fed to the plasma reactor shown in Fig. 6, where a plasma with a temperature of about 10,000 K was produced using air as the starting gas; the plasma arc rotated around the exposed anode at a speed of about 30,000 rpm, which resulted in the separation of a useful mineral fraction weighing 2.53 kg from the bulk material sample initially introduced into the reaction chamber, weighing 3.08 kg. The composition of this fraction, expressed as a percentage by weight, was as follows:

Al ₂ 0 ₃ 95.0%

TiO ₂ 2.7%

Impurities 2.3%

Thus, in a two-stage process, the Al ₂ O ₃ and TiO fraction was obtained with a purity of 97.7% by melting the Al ₂ O ₃ and TiCO in plasma and recovering the unresolved aggregate that collected at the bottom of the reaction chamber of the reactor shown in Figure 6. .

The 0.55 kg fraction, which was the remainder of the original 3.08 kg sample introduced into the plasma reactor, was removed from this reactor as further described with reference to the apparatus shown in Fig. 6. For example, most of the magnesium, iron and silicates from a 3.08 kg sample were melted in the plasma and crystallized as dust particles then blown out of the reactor. Also

The sulfates evaporated in the plasma to form gas that was also blown from the reactor. The entire remaining 0.55 kg fraction, including dust and gas particles, could be collected for further processing if necessary.

Example II. Figure 2 shows another embodiment of the invention where slag from a foundry producing iron-chromium products was used as the bulk material. It should be added that mine slag was also processed by the method according to the invention. A sample of blast furnace slag was taken from the heap. The slag sample was screened to remove excess billets, and the remaining bulk material was subjected to a magnetic screening technique whereby billets larger than 250 mm in diameter were separated from the remaining bulk material. This screened fraction of billets with a diameter of 250 mm and above contained 75% (by weight) of iron and 25% by weight of chromium compounds. A sample weighing 10 kg of the remaining smaller diameter particulate material had the following composition expressed as a percentage by weight:

SiO ₂ 25% 3% CaO 45% Fe ^ O, 7% MgO 8% Cr chromium oxide 12% chromates

The ti 10 kg sample was then crushed and ground such that the particles were reduced to an average diameter of from about 0.1 to about 0.2 mm. These ground particles were introduced into the flotage chamber of the pneumogravity separation device shown in Figure 5. In this device, the particles came into contact with a laminar flow of flotation air flowing through the chamber from an inlet on one side to an outlet on the other side of the chamber. The air velocity was about 10 m / s and the particles blown through the chamber fell out of the flotation stream in two separate fractions according to the weight of the particles. As a result of the gravitational fall, the first fraction contained the heavier particles and the second - the lighter ones. The obtained first mineral fraction, which fell from the flotation stream weighed 5.75 kg, was collected and subjected to a known magnetic separation process in order to separate the part (weighing 3.27 kg) rich in iron and chromium from the second part (weighing 2.48 kg ). The first part rich in iron and chromium was collected. The remaining second part, weighing 2.48 kg, had the following composition expressed as a percentage by weight:

Al ₂ O ₃ 6.06% CaO 66.522% SiO2 26.21% Cr ₂ ° ₃ 0.41% Fe ₂ O ₃ 0.40% MgO 0.41%

The second fraction obtained from the pneumogravitational separation step weighed 4.3 and had the following composition expressed as percentage by weight:

^k g ^Al 2 ^O 3

CaO

SiO ₂

Cr ₂ O ₃

Fe ₂ O ₃

MgO

3.49%

32.60%

39.56%

5.80%

4.65%

13.90%

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The second part from the magnetic separation process, weighing 2.48 kg, was combined with the second fraction from pneumogravity separation weighing 4.3 kg, yielding a combined sample weighing 6.78 kg, which was transferred to further treatment by chemical-thermal screening for extraction. from this product minerals of higher purity.

To a combined sample weighing 6.78 kg, approximately 0.72 kg of carbon particles were added to form a bulk mixture of 7.5 kg, which was then introduced into a plasma reactor of the type shown in Figure 6, where plasma was produced using air as a starting gas. at a temperature of about 10,000 ° K. The plasma arc rotated around the exposed anode at a speed of about 30,000 rpm, which resulted in the separation of a useful mineral fraction with the following composition expressed as a percentage by weight and a weight of 0.28 kg:

chromium mixture 85% iron mixture 14% impurity 1%

Thus, in a two-stage process, 99% pure minerals with a high percentage of chromium and iron, in the amount of about 0.28 kg, were obtained from loose raw materials. The remainder of the fraction collected from the chemical-thermal screening step in the reactor as shown in Figure 6, weighing 6.5 kg, contained valuable ingredients suitable for the production of valuable by-products such as Portland cement-like material.

Example III. Fig. 3 shows another embodiment of the invention, in which the residue obtained in the process of electroplating the production of high-quality steel was used as a raw material for recovering minerals. After the galvanization process, the residue was collected in the form of a sludge, which contained chromates, sulphates, chlorates, iron compounds and silicates. In particular, the precipitate contained a high percentage (more than 50% by weight) of chromium salts.

Initially, the sediment was dried with hot air. Then, the dried material was ground into particles with a diameter of no more than 2 mm. The bulk material prepared in this way was transported and introduced as a 10 kg sample into a pneumogravitational separation device of the type shown in Fig. 5, with the principle of operation shown below in the description of this drawing. The flow velocity of the lammonium air stream in the flotation chamber was about 5 m / s. A 4.5 kg loose fraction had fallen from the flotation stream and a 5.5 kg waste fraction remained suspended in the flotation stream.

The waste loose fraction from the pneumogravity separation stage with a predominance of chromium salts, chromates and iron and ferrous compounds was collected and transferred to the next treatment stage, i.e. for chemical-thermal screening in order to obtain a valuable mineral content of higher purity than the product obtained in the stage pneumogravitational separation.

The particles remaining in the flotation stream were collected separately as a valuable by-product suitable for use as a binder or in mines as a backfill.

In the chemical-thermal screening step, the precipitation fraction from the pneumogravity separation step was fed into the plasma reactor shown in Figure 6, where a plasma was produced at a temperature of about 10,000 ° K using methane as a reducing gas. The plasma arc rotated around the eight-membered anode at about 30,000 rpm, precipitating essentially pure elemental chromium, chromium salts, and elemental iron. This mixture of chromium and ferrous materials was subjected to an electromagnetic screening process to separate substantially pure chromium materials from substantially pure iron.

166 169

Example IV. Fig. 4 shows another embodiment of the invention, in which sand taken from the bottom of reservoirs such as an ocean, sea or lake was used as a raw material for obtaining valuable minerals. Preferably, sand for this purpose, hereinafter referred to as sea sand, is taken from the vicinity of a mine or industrial plant that discharges sewage into a given water reservoir. In this example, a 10 kg sample of sea sand was used as the mineral source. This sample contained the following minerals in the percentages by weight listed below:

ilmenite 28.0% zirconium 20.7% rutile 7,:?% monacyt 1.5% grenade 34.2% amphibole 3.8% epidote 3.1% tourmaline 1.4%

a kilogram sample of sea sand was first introduced into a weak magnetic sifter, down to about 5 kilogaus, to screen out the highly magnetic ferrous material fraction from the non-magnetic and lower magnetic components of the sample. The thus separated high magnetic fraction weighed 2.8 kg and contained 97% ilmenite and 3% of such minerals as garnet, amphibole, epidote and tourmaline. This magnetic fraction was then introduced in a loose form into a plasma reactor of the type shown in Figure 6, where this bulk material was subjected to the chemo-thermal treatment described in connection with the operation of such a reactor. At this stage, iron with a purity of 98.6% and TiP2 with a purity of 99.4% were obtained from the ilmenite-rich fraction.

The remaining non-magnetic and lower magnetic fraction, weighing 7.2 kg, was transferred from the magnetic sifter and subjected to electrostatic sieving using a positive potential of up to 50 kV. Electrostatic sifting caused the division of the fraction subjected to this process into two portions. One batch of conductive materials weighed 2.9 kg, while the other batch of dielectrics and non-conductive materials weighed 4.3 kg.

The first batch of conductive materials contained materials such as garnet, amphibole, epidote, tourmaline, and rutile. It was then sent for further processing to separate the semi-magnetic materials contained therein from the non-magnetic fraction by subjecting a 2.9 kg sample to a magnetic sieve in a strong magnetic field of up to 16 kilogaus. The separated semi-magnetic material weighing 1.6 kg was the remainder of the process. The rest of the screened material, weighing 1.3 kg, was collected and cleaned in another electrostatic treatment process, in which the remaining dielectric materials were removed, and the conductive materials, weighing 7 kg and containing 96% rutile concentrate with 4% addition of impurities, mainly such as garnet and zirconium , amphibole, epidote and tourmaline, were collected and processed in a plasma reactor of the type shown in Figure 6 and operated as detailed below. The mixture obtained as a result of the chemical-thermal treatment in the plasma reactor contained TiO _: with a purity of 99.8%.

In addition, as mentioned above, a second batch of dielectric and non-conductive materials weighing 4.3 kg was collected, which was also magnetized under a strong magnetic field of up to 16 kilogaus, which resulted in the separation of two additional fractions. One of them contained mineral magnetic materials and weighed 0.5 kg. This magnetic fraction contained 98% pure monasite and 7% of impurities such as zircon, garnet, amphibole, epidote and tourmaline. This 98% monazite fraction was collected and treated in a plasma reactor to obtain 99.3% pure lanthanum oxides.

166 169

The non-magnetic fraction separated from the above-mentioned two fractions weighed 4.15 kg. It was transferred to the further electrostatic screening, where the zirconium concentrate was obtained as a dielectric product of the electrostatic screening and the conductive residue. The zirconium concentrate weighed 2.1 kg and contained 97% ZrSiO4 and 3% impurities, mainly consisting of rutile and small amounts of other materials such as garnet, amphibole, epidote and tourmaline. This zirconium concentrate was also chemically heat treated in a plasma reactor of the type described and shown in Figure 6 to obtain 99.5% pure ZrO2 and 99.8% pure SiO2.

The isolated conductive material weighing 2.05 kg was the remainder of the process, which was then combined with the residues of the previous stages and treated together as waste.

The invention is described in more detail in the following drawings. The following detailed description of the pneumogravity separation device is illustrated in Figure 5. Device 50 has an elongated housing 52 of rectangular cross-section. Housing 52 houses a flotage chamber 54 and an inlet 56 with a mating chute 58, such as, for example, a vibrating conveyor, leading to chamber 54 at a desired entrance angle. Housing 52 also has another inlet 60 through which air is introduced into chamber 54 by means of a fan or blower 62 permanently mounted near the first end 64 of housing 52. Housing 52 also has at least one outlet, illustrated as outlets 66 and 68 positioned to allow collection of waste mineral fractions obtained from the bulk material introduced into chamber 54 through inlet 56 and treated. The outlet 70 is located at the second end 72 of the housing 52, opposite its first end 64, to allow the reception of non-encapsulated fractions of the bulk material with mineral content constituting the residual waste fraction.

In a preferred embodiment, inlet 56 is disposed longitudinally with respect to the outlet at end 72 of housing 52 at a distance defined by the formula:

CHVM _g Fd ² y _c where C is the horizontal distance between the second inlet 56 through which the bulk material enters and the end of chamber 54 through which the particles leave chamber 54, C is the constant calculated on the basis of the Reynolds number and in the case of laminar air flow through the chamber 54 is 18, V is the velocity of the gas (e.g. air) flowing through the chamber 54, Mg is the dynamic viscosity of the gas, F is the cross-sectional area of chamber 54, d is the average diameter of the bulk particles entering chamber 54 through the second inlet 56, and y is the weight the specific particle size and H is the height of chamber 54.

During operation of the device 50, air is blown into the chamber 54 by the blower 62, which causes a laminar flow of the flotation stream along a constant horizontal axis 74 extending from the inlet nozzle 76 of the blower 62 to the end 72 of the housing 52. The particles are introduced into the chamber 54 through the inlet 56 and a chute. 58 is adjusted to provide the desired angle α for introducing the particles into the chamber 54. The angle α may be adjusted from about 2 to about 75 ° from the axis 74 to adapt the separation conditions to the weight of the various raw materials processed in the apparatus 50. Preferably, the chute is 58 is constructed to allow vibration or oscillation such that the particles introduced by chute 58 into chamber 54 are agitated sufficiently to prevent agglomeration. .

The legs 76 and 78 provide support for the housing 52 and a stable position relative to the floor 80. The apparatus 50 has conventional leg height adjusting mechanisms 82 and 84 mounted on legs 78 and 78 respectively. Mechanisms 82 and 84 operate independently to raise or lower housing 52 as needed to tilt chamber 54 in housing 52 as desired, allowing adjustments to be made.

The angle β between the predetermined horizontal axis 74 and the longitudinal axis of the chamber 54. In this way, the fall path that the particles must travel between entering chamber 54 and contacting the air stream can be adjusted to accommodate raw materials of different weights of particles. In practice, it has been found that for best results this angular adjustment of the β angle should be possible in the range from about -60 to 0 ° (horizontally) for lighter mineral products and from +60 to 0 ° (horizontally) for heavier mineral products.

Figure 6 shows a schematic view of a plasma reactor 100, not included in the present invention, but serving - in a comprehensive process of obtaining valuable mineral substances from bulk materials - for the treatment of bulk materials such as non-precipitated mineral fractions recovered in the pneumogravitational separation process using the device 50 shown above. as discussed in Figure 5, or for treating any other bulk material.

Reactor 100 includes a plasma head 102 with a vertically mounted plasma thrower 104. The thrower 104 is shaped and dimensioned to inject the gaseous plasma so as to produce a downwardly directed, central arc or plasma jet 105 extending from the cathode 106 to the multi-membered assembly. annular anode 108 positioned in reaction chamber 110 downstream of head 102. Plasma head 102 includes shaped channels 116 that extend upward and communicate with a metering device (not shown) metering mineral-containing bulk material introduced into reaction chamber 110. Downstream of chamber 110 downstream of the plasma stream is a cylindrical cooling chamber 112 leading down to a conical section 114 into which air is fed countercurrently through an inlet 138 to blow out some of the remaining cooled materials exiting chamber 110 through outlet 140 as left , which is described in more detail below _EJ. _ _.

In operation, the particles upon introduction into chamber 110 come into contact with the plasma arc 105 and are heated to a high temperature in an environment in which the plasma arc 105 is circulating or spinning as shown by arrow A in Figures 7 and 8. at a speed higher than that achievable with the methods or devices used so far.

Figure 7 shows a particular embodiment of the plasma reactor in a downward view from cathode 106 to anode 108 along the plasma arc 105 in reaction chamber 110. The area between cathode and anode will hereinafter be referred to as reaction zone 118. Reaction zone 118 typically contains a suitable gas. to form a plasma, as between the anode 108 and the cathode 106 p _rz vein _{Zo n} s is sufficient connection with an external source (not shown in the drawing). Plasma arc path 105 from the cathode 106 to the anode 108 nazy _in a further _person ble _s trefy reaction. As shown in the drawing, the plasma arc 105 is directed from the cathode 106 to a lot _of membered anode ring 108 consisting of eight separate electrically from each other odi _the lead _n y _c h members, which in turn is directed plasma arc, resulting in _about B _ro ty of the arch. Ro _{of n} for human ed anode having at most six members has been previously described in U.S. Patent No. 4 361 441, the contents of which treats _t o _oo j _and k d _{n n} k axis literature disclosing the structure of the anode. In the device described _in this dock _with Me _n successive excitation of the members of the anode circulates the arc of up to _about 6000 k _{lo of} b _r ./min. according to the frequency of excitation of individual members. The second objective _{of the ne wenc} Use g _{of GM} wake _gs members - Anode switches are electric. For will help _n and _a rotation arc plaanowego device according to the cited U.S. Patent Zj _e d _noczon small _No. 4 361 441 also uses a rotating magnetic field, which thanks to the pl _with a _P sits down load causes the arc subjected to a force perpendicular to the _m applied field _n ag ethyl _totaling ego and the vector p _r ędkości arc. For creating a rotating magnetic field

1666 169 uses an array of cylindrical coils arranged around the edge of the plasma arc path and energized sequentially by an external source.

As already mentioned, the plasma reactor 100 uses a multi-membered anode 108, however, unlike the apparatus described above in U.S. Patent No. 4,361,441, no electrical switching circuits are used in the plasma reactor 100 to cause the plasma arc to jump over the air. from one anode segment 108 to the other. Instead, as detailed below, a magnetic field was used to swirl the plasma arc 105 through successive anode members 108 as shown by arrow A. This means that the rotation speed of the plasma arc 105 is independent of the frequency with which the states of the electrical switches can change. Thus, much higher engine speeds can be achieved - up to around 30,000 rpm. - than was possible with previous devices.

As shown in Figures 7 and 8, the multi-segment annular anode 108 has a plurality of cylindrical coils 120 arranged circularly along the edge. Each of the coils 120 is wound on a low magnetic resistance ring core 122 whose axis is oriented perpendicular to the axis of the reaction zone 118. In the preferred embodiment of this device there are two such coils 120 for each anode member 108 positioned 90 ° on each side. of a given element. Thus, the total number of coils 120 is twice the number of anode members 108. Figures 7 and 8 show an eight-membered anode with members separated by insulating material 124. However, for simplicity in Figure 7, only four coils are shown labeled 120a, 120a '. , 120b, 120b '. The anode member 108a is electrically connected to the coils 120a and 120a 'and the anode member 108b to the coils 120b and 120b'. Coils 120a and 120b are wound on the same portion 126 of core 122 in reverse directions. Likewise, the coils 120a 'and 120b' are wound on the opposite portion of the core 122. Each of the coils 120 is also connected to the electrical ground identified by element 130. Thus, at each anode member a constant electrical potential is maintained through two paths to the ground through the coil. cylindrical 120 located at the edge of reaction zone 118 and oriented so that its longitudinal axis is perpendicular to a line drawn from the center of the annular anode 108 to the particular anode member to which it is attached. When a discharge of the plasma arc 105 occurs between the cathode 106 and a given anode member, an electric current flows through the anode member and into the ground to energize two cylindrical coils associated with the member (i.e., coils 120a and 120a '). The function of the coils 120 is to create a magnetic field oriented radially and directed towards (or away from) the anode member conducting the plasma discharge. As shown in Figure 7, when excited, a pair of coils 120a and 120b arranged on opposite sides of the edges of the arc path produces a radially oriented magnetic field vector B _b The magnetic field Bj thus causes the plasma arc 105 to undergo a circumferential force at right angles to B _b which is proportional to the axial velocity along the path from the cathode to the anode.

Thus, plasma reactor 100 operates as follows. All the anode members are grounded (or connected to another constant potential region) through separate paths, each passing through a cylindrical coil 120. After cathode pre-excitation, when the gas breakdown potential is reached, a plasma discharge occurs in the reaction chamber between cathode 106 and one among the anode members 108 and a plasma conductive path is formed. In the absence of other forces, the discharge would remain stationary or would jump randomly from one anode member to another. However, the magnetic field, B, forces the arc to move around the circumference and causes it to jump to the adjacent anode member. This anode member in turn excites another pair of cylindrical coils, which causes the plasma arc to rotate further to the adjacent anode member, and so on. Thus, the plasma arc must rotate continuously, at a speed independent of the frequency of any electrical switching.

166 169

In order to give the plasma an even greater angular velocity in reactor 100, another cylindrical coil 132 is wound around the edge of the reaction zone 118 and coaxial with the axis of the reaction zone 118. Excited by an external power supply, the coaxial cylindrical coil 132 thus creates another magnetic field B2 directed towards axially along the plasma arc path shown in Figure 8. The B2 field causes all charged particles moving with a radial or circumferential velocity component to be under the influence of a force directed perpendicular to this velocity component. The velocity component directed along the radius is imparted to the plasma arc by arranging the anode members along the edge, which causes the plasma arc to swing outwards along the radius. Thus, the magnetic field B2 transforms the linear moment of the charged particles motion directed along the radius into an angular moment, causing the moss to rotate. Moreover, the peripheral component of the rotating plasma velocity (caused by both the magnetic fields B 1 and B2) thus created is subject to the action of the field B2, which draws the arc radially inward. This in turn provides the centripetal force necessary to maintain the fast rotation.

The hitherto methods of forcing the plasma arc to rotate, such as those described in the previously cited United States Patent No. 4,361,442, were based solely on the spinning of an external magnetic field set in rotation by means of electric switches and the subsequent excitation of the anode members also by means of electric switches. This means that the angular velocity of the plasma could not be greater than the electrical switching frequency. In contrast, the present device has no such limitations and is therefore capable of imparting to the plasma arc a much higher rotational speed.

Thus, in the practical use of this device in a comprehensive method of obtaining valuable minerals from bulk materials containing minerals, atmospheric air or pure oxygen was used as a plasma gas to produce pure alumina and titanium oxide from the fly ash fraction deposited in the pneumogravity separation stage. The temperature generated in reaction chamber 110 of plasma reactor 100 was about 10,000 ° K, and the forced arc speed around the perimeter of the eight-membered anode 108 was about 16,000 rpm. The bulk material was introduced from above into the vertically oriented reactor chamber 110 through channels 116 at a rate such that the particles spiraled through the plasma arc at a rate of about 5 kg / sec.

As the particles descend through the plasma arc in the reaction chamber 110, their valuable minerals (such as alumina and titanium oxide) melt, while the remaining bulk material components, such as magnesium, either crystallize or evaporate. Upon exiting reaction chamber 110, after passing near the anode 108, materials enter cylindrical cooling chamber 112 and descend from there through temperature gradients, while molten minerals concentrate into relatively dense particles, crystallized residues form dust particles, and vaporized components form gases. . Then, as the cooled components reach the lower sections of the cooling chamber 112, they reach the delivery plate 134, the purpose of which is to separate relatively denser mineral agglomerates such as alumina and titanium oxide from other falling materials. In addition, the plate 134 directs the separated mineral particles downward through the conical section 114 in the correct direction to allow them to be collected at the bottom 136 of the conical section 114.

In section 114, a swirled countercurrent air is directed upwards from inlet 138 to outlet 140 to cause the accompanying mineral pellets of dust particles and gases to be blown out of the reactor 100 through an outlet pipe 141 fitted at the outlet 140.

The outlet pipe 142 is structurally associated with the inlet 138. The axis 144 of the pipe 142 is oriented at an angle X to the horizontal axis 146 and passes through the center point of the inlet 138. Thus, the angle X generally defines the angle of the air inlet to the conical section 114 of the reactor 100.

166 169

In a preferred embodiment of this device, the angle X should be approximately 15 °. However, the magnitude of the angle X for any particular process depends on various factors, including the velocity of the air introduced through the inlet 138, the specific gravity of the materials treated, and the angle of the cone (Y angle in Figure 6). In this connection, it should be noted that for very high specific gravity materials, the angle X may be increased up to 90 [deg.] (Then air will be introduced from the bottom 136 of the cone 114).

Preferably, the inclination angle Y of the cone 114 is approximately 30 °. However, it has been found experimentally that for the processing of materials with a high concentration of iron and chromium, such as raw materials from foundries, the angle X should be between about 0 ° to about 37 ° and the angle Y should be between about 10 ° and about 30 °.

For raw materials with a high concentration of copper, nickel or cobalt, such as those from mines and foundries, the angle X should be between about 5 ° and about 30 ° and the angle Y should be between about 15 ° and about 40 °. For high concentration zirconium raw materials, such as sea sand raw materials, the angle X should be between about 0 ° and about 15 ° and the angle Y should be between about 30 ° and about 40 °. For high alumina and titanium oxide materials, the angle X should be between about 0 ° and about 30 ° and the angle Y should be between about 20 ° and about 40 °.

To accommodate such a large variety of angular configurations for the various raw materials, in one version of the device 100, the reactor conical section 114 is provided as a replaceable part, so that differently shaped tips can be installed on the reactor body 100 as required.

Another important design feature of the conical section 114 of the reactor 100 is the location of the inlet 138 and associated air inlet 142. It has been found that in a preferred embodiment, the center point of inlet 138 should be at a height h above the bottom 136 of the conical section 114, i.e. 1/4 of the total height h _{s of} section 114. The height h _s for any version of the cone section 114 can be calculated as a function of the Y angle of the cone 114 from the equation:

hs = 1/2 d _s tgY where ds is the diameter of the cone 114 at the horizontal upper truncation 148 of the conical section 114, the diameter ds of the cone section 114 can be calculated from another equation:

^ = 1.24 with cf being the radius of the cylindrical cooling chamber 112.

Another important design feature of the reactor 100 is a wall section 150 disposed at right angles to the horizontal base 148 of the cylindrical cooling chamber 152 of the cylindrical cooling chamber 112 and to the horizontal top 148 of the conical section 114. The wall 150 circumferentially connects and seals the chamber 112 to the conical section 114. In a preferred embodiment, wall 150 is positioned at an angle Z to the horizontal cap 148 of section 114. This angle is selected such that air entering section 114 through inlet 138 at angle X is directed through wall 150 in a desired upward direction. it comes into contact with the material falling downward of the cooling chamber 112, and so that the relatively lighter dusts and gases therein move upwards through the centrally located funnel 154 to meet the falling particles and that these lighter materials are directed to the outlet 140. from where they exit via the outlet pipe 141 and are collected as waste products from chemical-thermal separation.

In a preferred embodiment of the reactor 100, the angle Z may range from about 35 ° to about 60 °, most preferably 45 °. However, the angle Z may be varied as needed to obtain optimal aerodynamic conditions within the conical section 114 for directing the air introduced through the inlet 138 to the outlet 140, either by a direct, swirled, spiral or rotating stream.

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If desired, a ventilation device (not shown in Figure 6) can be connected with an exhaust pipe 171 to facilitate the collection of waste materials.

The velocity of the air introduced into the conical section 117 is another important factor affecting the operation of the reactor 100. For example, it has been found that in general, the velocity of the air entering section 117 through the inlet 138 should be in the range of 1 to 20 m / s. The air velocity is regulated according to the density of the recovered minerals, generally using higher speeds for the heaviest particles such as iron-chromium, while lower speeds are used for materials with lower specific gravities. For example, when fly ash is used as feedstock in the reactor, it has been found that the conical section 114 of the reactor 100 is fed through the inlet 138 with air, expelled to a velocity of about 1.7 m / s.

In addition, it has been found that for some applications of reactor 100 it may be desirable to incorporate an electromagnet 156 surrounding a ring-shaped lower section of cylindrical cooling chamber 112. In particular, to perform some screening operations on plasma treated materials derived from metallurgical slag or foundries, operation of the solenoid 156 may assist. in sifting mineral materials from residues. However, when treating fly ash, such electromagnetic assistance is usually not needed.

While the invention has been described in detail in the preferred embodiment, it should be understood that the foregoing description has been presented merely for the purpose of illustrating the invention. Numerous changes to the details and individual operating steps of the method according to the invention as well as to the properties of the treated materials are permissible and do not depart from the spirit and scope of the invention as defined in the claims.

Claims (22)

Patent claims A method of pneumogravitational separation of valuable minerals from a bulk material containing minerals, characterized in that the loose material containing minerals is introduced into the flotage chamber of the pneumogravity sieving device having at least one inlet and a plurality of outlets through which the flotation stream can flow from at least one inlet to at least one outlet, this feedstock is flotated by contacting it with a flotation stream at a predetermined air flow velocity sufficient to cause the feed to be separated into at least one valuable mineral fraction which precipitates from the flotation stream by gravity the fall of this fraction from the stream under the weight of a valuable mineral substance and onto a waste fraction remaining in the flotation stream, and the at least one precipitated mineral fraction is collected with one of the following: at the flotation cell outlets, and the rest of the waste fraction at the other outlets. 2. The method according to p. The method of claim 1, wherein the mineral-containing bulk material is moistened with a sulfuric acid solution prior to being introduced into the flotage chamber. 3. The method according to p. The process of claim 1, wherein the flow rate of the flotation stream is kept between 2 and 25 m / s. 4. The method according to p. Process according to claim 1, characterized in that the treatment of the bulk material has a grain size with a radius smaller than about 0 and mm. 5. The method according to p. Process according to claim 4, characterized in that the treatment of a bulk material obtained by crushing a solid raw material containing minerals. 6. The method according to p. Process according to claim 1, characterized in that a material selected from the group consisting of: fly ash, furnace dust, slag, coal, foundry waste, metallurgical waste, mine tailings, sea sand and mixtures thereof is treated. 7. The method according to p. The process of claim 6, characterized in that the treated waste is slag produced in the iron-chromium production process. 8. The method according to p. The process of claim 6, characterized in that the fly ash produced from the blast furnace slag is treated. 9. The method according to p. The process of claim 1, wherein the bulk material is treated with a sulfuric acid solution prior to entering the flotage chamber. 10. The method according to p. The process of claim 1, wherein a fraction belonging to the group consisting of: alumina, titanium oxide, iron, chromium, nickel, cobalt, lead, zinc, copper, zircon and mixtures thereof is collected as a valuable mineral fraction. 11. The method according to p. Process according to claim 1, characterized in that the collected waste fraction is further processed to produce a building material with the characteristics of cement. 12. The method according to p. A method as claimed in claim 1, characterized in that the bulk material is introduced into a pneumogravity separation device having an elongated flotage chamber with a first inlet and a first outlet, means for introducing air into the chamber through the first inlet, and forcing the chamber to flow through and out through the first outlet, the second inlet. for introducing the bulk material into this chamber so that it can be brought into contact with the flotation stream, located in the flotage chamber at a sufficient distance from the first outlet that at least one mineral fraction can separate and fall out of the flotation stream by gravity settling under the weight of the sub166 169 minerals contained in this fraction, and at least one such mineral fraction is collected from the device. 13. The method according to the above mentioned above, characterized by the fact that loose matter is fed into the flotation chamber through the second inlet located at a distance from the first outlet defined by the formula: C HVM _g Fd ² Yc where C is the horizontal distance between the second inlet and the first outlet, C is the constant coefficient calculated on the basis of the Reynolds number, V is the velocity of the gas (air) flowing through the flotation cell, Mg is the dynamic viscosity of the gas, F is the cross-sectional area of the flotage cell, d is the mean diameter of the particles introduced into the flotage cell, γ. is the specific gravity of the particles and H is the height of the flotation chamber. 14. The method according to p. The method of claim 12, characterized in that the bulk material is introduced into the flotage chamber through the second inlet with a structure enabling the adjustment of the angle of introduction of this material. 15. The method according to p. The method of claim 14, characterized in that the bulk material is introduced into the flotage chamber at an angle of approximately 12-75 ° to the direction of air current flow through the chamber. 16. The method according to p. 12. The method of claim 12, characterized in that the bulk material is introduced into a device additionally equipped with a flotage chamber tilting mechanism enabling the adjustment of the angle between the horizontal direction of air current flow through the chamber and the longitudinal axis of the chamber. 17. The method according to p. 16. The apparatus as claimed in claim 16, characterized in that the angle between the horizontal direction of the air current flow through the chamber and the longitudinal axis of the chamber is adjustable from approximately -60 to + 60 °. A device for the pneumogravity separation of valuable minerals from mineral-containing bulk materials, characterized in that it comprises a flotation chamber (54) of oblong shape, in a housing (52) having a first inlet (60) and a first outlet (70), means (62, 76) for introducing air into the chamber (54) through the first inlet (60) and for forcing air to flow through the chamber (54) from the first inlet (60) to the first outlet (70) to provide a flotation stream of air in the chamber (54) flowing from the first inlet (60) to the first outlet (70) and the second inlet. (56) for introducing the bulk material therein and bringing it into contact with the flotation stream, the second inlet (56) being located in the chamber (54) at a sufficient distance from the first outlet (70) to allow the separation of valuable minerals contained in the bulk material in the form of at least one valuable mineral fraction and its fallout from the flotation stream as a result of gravity settling under the weight of valuable minerals contained in that fraction, and a second outlet (66) for receiving the separated mineral fraction. 19. The device according to claim 1 Ig, significant in that the distance between the first inlet (56) and the first outlet (70) is given by the formula: CH V Idg? / ² c {c where C is the horizontal distance between the second inlet (56) and the first outlet (70), C is the constant coefficient calculated on the basis of the Reynolds number, V is the velocity of the gas (e.g. air) flowing through the chamber ( 54), Mg is the dynamic viscosity of the gas, F is the cross-sectional area of the chamber (54), d is the average diameter of the bulk material particles entering the chamber, (54) through the second inlet (56), y _c is the specific weight of the particles and H is the height chambers (54). 166 169 20. The device according to claim 1 18. The apparatus of claim 18, characterized in that the second inlet (56) has a structure (58) for adjusting the angle a for introducing the bulk material into the chamber (54). 21. The device according to claim 1 20, characterized in that the angle α of the introduction of the granular material is 12-75 ° to the direction of the air current flowing through the chamber (54). 22. The device according to claim 22 18. The device according to claim 18, further comprising a chamber (54) tilting mechanism (82, 84) for adjusting the angle (3 between the horizontal direction of air flow through the chamber (54) and the longitudinal axis of the chamber. 23. The device according to claim 1 22, characterized in that the angle β ranges from -60 to + 60 ° with respect to the horizontal direction of the air flow.