Process for obtaining co-products from copper mining tailings

Abstract

The present invention relates to a process for obtaining co-products from the tailings generated in the flotation of copper sulphide ores, said process comprising magnetic separation as a rougher stage, ultra-fine grinding, magnetic separation as a cleaner stage and reverse cationic flotation of silicates as a recleaner stage. This process involves processing the tailings to produce a magnetic iron ore concentrate (magnetite) that meets the following specifications: >64.10% Fe, <2.50% SiO2, <2.00% Al2O3, <0.065% P and <0.25% Mn. In addition, the present invention relates to the processing of intermediate tailings generated throughout the proposed process for obtaining copper and gold concentrate and for generating additional co-products for the construction industry and for road paving, as well as for use as mineralisers or soil conditioners.

Description

PROCESS OF OBTAINING CO-PRODUCTS FROM COPPER MINING WASTE. FIELD OF INVENTION

[0001] The present invention relates to a process for obtaining by-products from tailings from the beneficiation of copper ore. In particular, the present invention relates to tailings from the flotation of copper sulfide ores. The process proposed here involves the beneficiation of the tailings to produce a magnetitic iron ore concentrate (magnetite) or magnetitic pellet feed that meets the following specifications: >64.10% Fe, <2.50% SiCe, <2.00% Al2O3, <0.065% P, <0.25% Mn, and 100% <0.300 mm. Furthermore, the magnetitic concentrate obtained has low contents of the following minor elements: Cu, Cr, S, V, Ti, F, Cl, and U, some of which are beneficial in the production of different types of steel (such as Cu and Cr in increasing resistance to atmospheric corrosion, and V and Ti in increasing mechanical strength).

[0002] Furthermore, the present invention encompasses the treatment of intermediate waste generated throughout the proposed process to obtain copper and gold concentrate and additional by-products for the construction industry and road paving. These by-products can also be used as mineralizers or soil improvers, supporting the circular economy. The magnetite concentrate, in turn, can serve as a raw material for the production of pellets, briquettes, or metallic iron for use in steel production with lower CO2 emissions throughout the production chain. BACKGROUND OF THE INVENTION

[0003] In the processing of copper sulfide ores, a large amount of tailings is generated, which must be properly disposed of in stockpiles or dams. These tailings account for between 95% and 98% of the copper ore mass fed to the processing plant. copper ores by flotation and may contain a significant amount of magnetite in their composition, which can vary between approximately 5% m / m and approximately 20% m / m. In addition to magnetite, the tailings from the flotation of copper sulfide ores may contain copper, gold, and other silicates in their composition.

[0004] With a view to maximizing the use of mineral resources, recovering magnetite from copper ore processing tailings appears to be a promising strategy. In this context, it is important to note that copper ores from iron oxide-copper-gold deposits (IOCG) contain between approximately 5% and 20% w / w magnetite (FeO, FeOs, or FesC), and this mineral is predominantly used as tailings in the copper ore flotation process.

[0005] Furthermore, the relevant environmental agencies have requested alternative studies for the reuse and disposal of tailings generated by mining activities, which results in a reduction in the volume of material disposed of in dams. Thus, the process for obtaining byproducts from tailings from copper ore processing, as proposed by this invention, is aligned with this context.

[0006] The present invention proposes a process route for generating co-products from tailings generated in the flotation of copper sulfide ores. This process route involves the beneficiation of the tailings to produce a magnetitic iron ore concentrate (magnetic concentrate or magnetitic pellet feed), comprising magnetic separation as the rougher stage, ultrafine grinding (Pgo = 20 pm), magnetic separation as the cleaner stage, and reverse cationic flotation of silicates as the recleaner stage. In this context, samples of magnetitic concentrate or magnetitic pellet feed with contents of 70.20% Fe, 2.03% SiO2, 0.45% Al2O3, <0.25% Mn, <0.065% P, 1000 ppm Cu, 14 ppm gold, and particles 100%<0.30 mm.

[0007] Furthermore, the proposed process route generates intermediate tailings with low magnetite contents (<0.50%), which are further processed to generate copper and gold concentrate and additional by-products for the construction industry and road paving, as well as for use as mineralizers or soil amendments. In this context, it is worth mentioning that magnetite (FesC) is a deleterious mineral in tailings used to generate by-products for construction, as it tends to oxidize to hematite (FeOa) over time, causing cracks and loss of mechanical strength in materials used in construction and road paving. Furthermore, it is poorly soluble and unable to neutralize soil acidity, also hindering the use of tailings containing magnetite as a mineralizer or soil amendment.

[0008] The state of the art concerning the present invention reveals efforts related to the recovery of minerals from copper ore tailings, including magnetite.

[0009] The scientific article entitled "Maximizing the recovery of fines using magnetic separation" refers to the recovery of fine magnetite in the form of pellet concentrate from iron ore tailings from an iron oxide copper-gold (IOCG) deposit. In this context, this document reveals a route involving rougher, cleaner, and scavenger magnetic separations and proposes an economically viable flowchart to maximize the recovery of fine magnetite. However, this route includes a preliminary step of hydrocycloning the copper flotation tailings and classifying particles up to 25 pm, ultimately obtaining a pellet concentrate with an Fe content of 67.5% and a SiC of 6%. Unlike the present invention, this document does not include a recleaner step for reverse silicate flotation. Therefore, the document in question deals with a tailings with approximately 25% by mass of magnetite (above the magnetite contents treated by the present invention).

[0010] Patent document IN201641022228A refers to a method of extracting recoverable minerals and metals from copper ore tailings, which is not limited to the concentration of magnetite, and comprises the combination of gravity separation, high-intensity magnetic separation, flotation and electrostatic separation.

[0011] Patent document CN109127122B, in turn, although it does not mention a starting material consisting of copper ore beneficiation tailings, discloses a process route for extracting iron and reducing silica from magnetite concentrate, which includes magnetic separation and reverse cation flotation. However, the process proposed by this document is particularly suitable for magnetite concentrates with an iron content between 62% and 65% (significantly higher than the magnetite contents treated by the present invention).

[0012] As explained above, prior art efforts are dedicated to obtaining recoverable by-products from copper mining tailings. Furthermore, the prior art also envisages solutions for concentrating magnetite through process routes involving magnetic separation and reverse silicate flotation. However, there remains a lack of an integrated process route for generating by-products that is economically efficient and eliminates up to 100% of the amount of copper ore processing tailings disposed of in dams or stockpiles.

[0013] As will be further detailed below, the present invention aims to solve the deficiencies of the prior art described above. SUMMARY OF THE INVENTION

[0014] The present invention relates to a process for obtaining co-products from the waste generated in the flotation of sulphide ores. copper, the aforementioned process comprising magnetic separation as a rougher stage, ultrafine grinding (Pgo=20 pm), magnetic separation as a cleaner stage, and reverse cationic flotation of silicates as a recleaner stage. In this context, the process in question is particularly aimed at obtaining magnetitic concentrate or magnetitic pellet feed from copper flotation waste.

[0015] Optionally, the process of the present invention comprises integrated routes for the tailings from the magnetic rougher separation, the magnetic cleaner separation, and the reverse cationic silicate flotation recleaner to obtain copper and gold concentrate and additional byproducts. According to the present invention, the tailings from the magnetic rougher separation are sent to thickening and filtration steps, and the tailings from the magnetic cleaner separation and / or the reverse cationic silicate flotation recleaner are sent to dilution, Cu and Au rougher flotation, Cu and Au cleaner flotation, thickening, and filtration steps. Furthermore, the tailings from the Cu and Au rougher flotation can also be sent to a Cu and Au scavenger flotation step. The Cu and Au scavenger flotation tailings, with low levels of these elements or free of them, are the final tailings and the Cu and Au scavenger flotation concentrate is recycled to the process route for obtaining Cu and Au concentrate.The waste from the Cu and Au scavenger flotation, free (or with low levels) of Cu, Au and magnetite, but containing silicates in its composition, can be thickened and filtered, and used to obtain additional co-products for civil construction or as a mineralizer or soil corrective.

[0016] The present invention aims to maximize the use of mineral resources derived from the tailings of copper sulfide ore flotation processes through an integrated process for the generation of magnetite pellet feed, as well as Cu and Au concentrates and additional silicate co-products. Thus, the present invention allows industrial operations for obtaining copper sulfide concentrates to be streamlined. more sustainable and supports the circular economy by utilizing up to 100% of the entire waste mass from copper production.

[0017] The mentioned objectives and other advantages of the present invention will become more evident from the description that follows. BRIEF DESCRIPTION OF THE FIGURES

[0018] Figure 1 illustrates an operational flowchart of the route for obtaining co-products from waste originating from the flotation of copper sulfide ores of the present invention.

[0019] Figure 2 illustrates the mineralogical analysis of a reject sample tested as raw material for the process route of the present invention.

[0020] Figure 3 illustrates a block diagram of the integrated route for obtaining copper and gold concentrate to which the tailings from the magnetic separation cleaner and / or the reverse cationic flotation of silicates recleaner are subjected. DETAILED DESCRIPTION OF THE INVENTION

[0021] In order to achieve the objectives described above, the present invention provides a process for obtaining co-products from waste originating from the processing of copper ore.

[0022] According to the present invention, the raw material for the process in question consists of tailings from the flotation of copper sulfide ores. Preferably, the raw material for the process in question consists of rougher tailings from the flotation. Said tailings comprise an amount of magnetite in its composition between approximately 5% m / m and approximately 20% m / m, preferably between approximately 10% m / m and approximately 15% m / m. Regarding particle size, the tailings have a Pgo between approximately 106 pm and a top size of 300 pm.

[0023] Figure 1 illustrates an operational flowchart of the route for obtaining co-products from waste from the flotation of copper sulfide ores of the present invention. All the processes are detailed below. stages of the proposed route.

[0024] Initially, the raw material (1) is taken to a preliminary dilution stage, in which the reject is diluted with process water to obtain a pulp with approximately 25% to approximately 35% solids (reject pulp) (2).

[0025] Next, the reject pulp (2) is subjected to a magnetic separation step (rougher stage) in drum-type magnetic separators with rotation between approximately 10 and approximately 30 rpm, preferably 15 rpm, and with a magnetic field between approximately 600 and approximately 1200 Gauss, preferably 1000 Gauss. The magnetic concentrate obtained in this step (rougher magnetic concentrate) (3) is classified by means of hydrocyclones into fractions smaller and larger than 20 pm, and the fractions larger than 20 pm (hydrocyclone underflow) are subjected to grinding to be added to the stream of fractions smaller than 20 pm (hydrocyclone overflow). Said ultrafine grinding establishes Pgo between approximately 10 pm and 50 pm, preferably Pso of approximately 20 pm.

[0026] Optionally, the non-magnetic reject from the magnetic rougher separation (non-magnetic rougher reject) (4) is taken to a thickening step with the addition of flocculant and a thickening rate ranging from approximately 0.050 m 2 / t / day and about 0.100 m 2 / t / day, preferably 0.050 m 2 / t / day. The thickener underflow containing thickened non-magnetic rougher reject (5) with approximately 50% m / m and approximately 65% ​​m / m solids, preferably 60% m / m solids, is then conveyed to a filtration stage in filter presses or under vacuum, with a filtration rate ranging from approximately 1000 to approximately 2000 kg / h / m 2 , preferably 1500 kg / h / m 2 to obtain non-magnetic rougher tailings with moisture content ranging from approximately 8% m / m to approximately 12% m / m, preferably 10% m / m. This thickened and filtered non-magnetic rougher tailings contains a low magnetite content (<0.50% m / m) and the presence of quartz and other silicate minerals in its composition, and may be used to obtain additional co-products for civil construction and road paving or used as a mineralizer and / or soil corrective.

[0027] The stream of fractions smaller than 20 pm from the magnetic rougher concentrate (3) is conducted to a thickening stage, in the presence of flocculant and with a thickening rate varying between approximately 0.020 m 2 / t / day and about 0.060m 2 / t / day, preferably 0.020 m 2 / t / day. The thickened magnetic rougher concentrate (6) is then passed on for a second dilution with process water to obtain a pulp with approximately 25% to approximately 35% solids (thickened magnetic rougher concentrate pulp) (7).

[0028] Then, the thickened magnetic rougher concentrate pulp (7) is subjected to a magnetic separation step (cleaner stage) in drum-type magnetic separators with rotation between about 10 and about 30 rpm, preferably 15 rpm, and with a magnetic field between about 600 and about 1200 Gauss, preferably 1000 Gauss. The magnetic concentrate obtained in this step (magnetic cleaner concentrate) (8) is taken to a third dilution with process water to obtain a pulp with about 25% to about 35% solids (magnetic cleaner concentrate pulp) (10).

[0029] The magnetic cleaner concentrate pulp (10) is then subjected to a reverse cationic silicate flotation step (recleaner stage), with a dosage of approximately 50 to approximately 250 g / t of FLOTIGAM® 17535 collector, preferably 90 g / t, and a dosage of approximately 5 to approximately 50 g / t of FLOTANOL® M28 frother, preferably 35 g / t. Both reagents are manufactured by Clariant. FLOTIGAM® 17535 collector was specifically developed for the family of complex silicates present in the magnetic cleaner concentrate generated in this invention and fed to the reverse silicate flotation step. This reagent allowed the reverse silicate flotation step to be made more selective, that is, with high metallurgical recovery of magnetite and achievement of the minimum desired Fe content in the product of this invention. The flotation time can vary between approximately 5 and approximately 35 minutes, preferably 20 minutes. The magnetite concentrate from this step (sunk or redeemer concentrate) (11) is taken to a thickening step, in the presence of flocculant and with a thickening rate between approximately 0.020 m 2 / t / day and about 0.040 m 2 / t / day, preferably 0.030 m 2 / t / day. The thickened redeemer concentrate (13) is then conveyed to a filtration stage in a filter press, with a filtration rate between approximately 1000 and approximately 2000 kg / h / m 2 , preferably 1500 kg / h / m 2to obtain magnetitic concentrate or magnetitic pellet feed with moisture ranging from approximately 8% m / m to approximately 12% m / m, preferably 10% m / m.

[0030] Optionally, the non-magnetic tailings from the magnetic separation cleaner (non-magnetic tailings cleaner) (9) will be sent to an integrated route to obtain copper and gold concentrate and additional co-products. In this context, this tailings is sent to a fourth dilution with process water to obtain a pulp with approximately 25% to approximately 35% solids (non-magnetic tailings cleaner pulp) (14).

[0031] Optionally, the tailings stream from the reverse flotation recleaner (floated or tailings recleaner) (12) can be added to the non-magnetic tailings pulp stream from the cleaner (14) and processed for further recovery of Cu and Au.

[0032] Then, the non-magnetic cleaner reject pulp (14) is subjected to a rougher flotation step with the addition of conventional copper collectors, such as amyl xanthate and / or dithiophosphate; and foaming agent, such as FLOTANOL®M28 and / or FLOTANOL®D25, with a flotation time varying between approximately 5 and approximately 30 minutes, preferably 10 minutes, and with pulp pH adjustment with the addition of 10% hydrated lime pulp. m / m for pH between 9 and 11, preferably for pH 10.

[0033] The tailings from the rougher flotation (Cu and Au rougher tailings) (16) are subjected to a scavenger flotation step with a flotation time ranging from approximately 5 to approximately 10 minutes, preferably 6 minutes, with or without the addition of collectors and / or frothers. The concentrate from this step (Cu and Au scavenger concentrate) (17) is mixed with the Cu and Au rougher concentrate (15), and the tailings from this step (Cu and Au scavenger tailings) (18) are taken to a thickening step in the presence of flocculant and with a thickening rate between approximately 0.010 m 2 / t / day and about 0.030 m 2 / t / day, preferably 0.020 m 2 / t / day. The thickened scavenger waste (19), without the presence of Cu and Au in its composition, or with very low levels of these elements, is then taken to a filtration stage in a filter press, with a filtration rate between approximately 500 and approximately 1500 kg / h / m 2, preferably 1000 kg / h / m 2 to obtain scavenger waste with moisture ranging from approximately 8% m / m to approximately 12% m / m, preferably 10% m / m, which can be used to obtain additional co-products for the construction industry, road paving or as a mineralizer or soil corrective due to the presence of silicates in its composition.

[0034] The Cu and Au rougher concentrate (15) mixed with the Cu and Au scavenger concentrate (17), in turn, is subjected to a cleaner flotation stage with a flotation time ranging from approximately 5 to approximately 35 minutes, preferably 20 minutes, and with pulp pH adjustment with the addition of hydrated lime pulp 10% m / m to a pH between 8 and 12, preferably to a pH of 10. The concentrate from this stage (Cu and Au cleaner concentrate) (20) is taken to a thickening stage, in the presence of flocculant and with a thickening rate between approximately 0.020 m 2 / t / day and about 0.040 m 2 / t / day, preferably 0.030 m 2 / t / day. The thickened cleaner concentrate (21) is then conveyed to a filtration stage in a filter press, with a filtration rate between approximately 1000 and approximately 1500 kg / h / m 2 , preferably 1250 kg / h / m 2to obtain Cu and Au concentrate with humidity ranging from approximately 8% m / m to approximately 12% m / m, preferably 10% m / m.

[0035] The reject from the cleaner flotation (Cu and Au cleaner reject) (22), in turn, is added to the non-magnetic cleaner reject pulp stream (14) and recycled to the rougher flotation stage of the aforementioned process route.

[0036] According to the present invention, for the thickening steps conducted in the above-described route, the flocculant is selected from the group including Flonex 934VHM, Magnafloc 10, Magnafloc 351, Magnafloc 1011, Magnafloc 338 and Praestol Kl 11-LA.

[0037] The description given thus far of the subject matter of the present invention should be considered only as one or more possible embodiments, and any particular features introduced therein should be understood only as something that was written to facilitate understanding. Therefore, they should not be considered as limiting the invention, which is limited to the scope of the claims.

[0038] The examples that will be presented below illustrate the scope of the products generated through the process proposed here. EXAMPLES EXAMPLE 1: Chemical analysis of waste from copper ore processing.

[0039] Table 1 shows the results of the chemical analysis of a reject sample tested as a raw material for the process route of the present invention. It can be seen that the reject has many deleterious elements in its composition and a low total iron content (<40%), with only between 30% and 50% of the total iron content coming from magnetite and the rest of the iron being originating from silicates, making the process of obtaining the desired high-quality magnetitic concentrate (>64.10% magnetitic Fe and <2.50% SiO2) quite challenging. Table 1: Chemical analysis of "rougher flotation tailings from copper ore flotation". EXAMPLE 2: Magnetic separation stage (rougher stage) of “rougher flotation waste from copper ore flotation”

[0040] A reject pulp with 30% solids was prepared. This pulp was subjected to magnetic separation in a drum with a feed rate of 55 kg / h. The dilution water flow rate was 150 L / h, with a magnetic field of 1000 Gauss, a 6.0 mm gap, and a drum rotation of 16 rpm. Table 2 shows the results obtained. It can be seen that a "magnetic rougher concentrate" with 60.88% w / w total Fe and 12.25% w / w SiO2 was generated, with metallurgical recoveries of 49.76% Fe and 10.22% Si. The mass and metallurgical recoveries of magnetite were 28.44% and 98.18%, respectively. The low iron recovery at this stage of the process is due to the presence of this element also in silicates. This “magnetic rougher concentrate” did not meet the specifications proposed by the present invention.The aforementioned "magnetic rougher concentrate" presented a coarse particle size (Pgo = 106 pm, 80% of the particles smaller than 106 pm), and the release study carried out in Quantitative Evaluation of Minerals by Scanning Electron Microscopy (QEMSCAN) indicated that 90% of the magnetite present in the magnetic rougher concentrate was released with a Pso of 20 pm. In order to meet the chemical quality expected in this invention, the magnetic rougher concentrate was ground in a vertical mill until reaching a Pgo of 20 pm. This stage also produces non-magnetic rougher waste with a low magnetite content (<0.50%), which can be used to obtain additional by-products for the construction industry, road paving, or as a mineralizer or soil improver due to the presence of silicates in its composition. Magnetite Contents Concentrated Magnetic 28.44 60.88 12.25 1.97 0.17 0.023 0.083 0.17 0.30 68.00 Rougher Reject No Magnetic 71.56 24.43 42.77 10.79 0.07 0.092 0.050 0.44 0.67 0.50 Rougher Distributions in % Element Fe Si Al Cu PS Ti Mn Magnetite Concentrated Magnetic - 49.76 10.22 6.77 49.11 9.04 39.75 13.31 15.11 98.18 Rougher Reject No Magnetic - 50.24 89.78 93.23 50.89 90.96 60.25 86.69 84.89 1.82 Rougher Table 2: Magnetic separation stage (rougher stage) of the “rougher flotation waste from copper ore flotation”. EXAMPLE 3: Magnetic separation stage (cleaner stage) of the “magnetic rougher concentrate”

[0041] A pulp with 30% solids content was prepared from the reject. This pulp was subjected to magnetic separation in a drum with a feed rate of 20 kg / h. The dilution water flow rate was 150 L / h, with a magnetic field of 1000 Gauss, a 6.0 mm gap, and a drum rotation of 16 rpm. Table 3 shows the results obtained. It can be seen that a "magnetic cleaner concentrate" with 67.39% w / w total Fe and 5.58% w / w SiO2 was generated, with metallurgical recoveries in the cleaner magnetic separation step of 89.63% Fe and 38.35% Si. The mass and metallurgical recoveries of magnetite in this step were 80.88% and 99.86%, respectively. This "magnetic cleaner concentrate" still did not meet the SiO2 content specification (<2.50% w / w) proposed by the present invention. Considering the magnetic separation steps (rougher, grinding, and magnetic cleaner separation) together, the mass recovery was 23.04%, and the metallurgical recovery of Fe and Si was 44.60% and 3.92%, respectively.At this stage, the non-magnetic cleaner waste is also obtained, used later for copper and gold recovery. Contents. Concentrated Magnetic 80.88 67.39 5.58 0.82 0.09 0.023 0.050 0.15 0.15 87.00 Cleaner Reject No Magnetic 19.12 32.98 37.95 6.55 0.49 0.095 0.213 0.28 0.89 0.50 Cleaner Distributions in % Element Fe Si Al Cu PS Ti Mn Magnetite Concentrated Magnetic - 89.63 38.35 34.62 43.72 50.60 49.82 69.38 41.62 99.86 Cleaner Reject No Magnetic - 10.37 61.65 65.38 56.28 49.40 50.18 30.62 58.38 0.14 Cleaner Table 3: Magnetic separation stage (cleaner stage) of the “magnetic rougher concentrate”. EXAMPLE 4: Silicate reverse flotation stage (recleaner stage) of the “magnetic concentrate cleaner”

[0042] Because the magnetic cleaner concentrate did not meet the SiO2 specification of <2.50% w / w, a cleaning study of the magnetic cleaner concentrate was conducted using reverse cationic silicate flotation. The magnetite concentration of the magnetic cleaner concentrate was performed using reverse silicate column flotation, since magnetite is concentrated in the sinking product and silicates (gangue) are concentrated in the floated stream. The flotation conditions, performed in a column, were: ❖ only one flotation stage (rougher flotation), ❖ conditioning times: FLOTIGAM®17535 collector: 1 minute and FLOTANOL®M28 (Clariant Sparkling Agent): 1 minute; ❖ 7.5 minute flotation time; ❖ air flow of 24.0 L / min; ❖ 90 g / t of FLOTIGAM® 17535 reagent (Quaternary Base + Primary Amine), trade name FLOTIGAM 14725 supplied by Clariant and 10 g / t of FLOTANOL®M28 foaming agent; ❖ without adding depressant; ❖ Natural pH of 8 (no need for lime dosage).

[0043] Table 4 shows the results obtained. It was possible to generate a "magnetic recleaner concentrate" (magnetic pellet feed or magnetitic concentrate) with 70.20% w / w total Fe and 2.03 m / w SiO2, with metallurgical recoveries in the reverse silicate flotation stage of 77.96% Fe and 29.36% Si. The mass and metallurgical recoveries of magnetite in this stage were 74.76% and 84.91%, respectively. This "magnetic redeemer concentrate" or magnetitic pellet feed or magnetitic concentrate met the specification proposed by the present invention. Considering the magnetic rougher separation, magnetic cleaner separation, and reverse cationic silicate flotation steps together, the mass recovery was 17.20%, and the metallurgical recovery of Fe, Si, and magnetite was 34.77%, 1.15%, and 83.26%, respectively. This step also produces the non-magnetic redeaner tailings, which will be used later for copper and gold recovery. Contents Rec „ Description Mass 'a Fe SiO2A12O3 Cu P (%) S c (%) . Ti Mn Magnetite Concentrated Magnetic 74.76 70.20 2.03 0.45 0.05 0.004 0.005 0.13 0.08 95.00 Recleaner Reject No Magnetic 25.24 58.78 14.47 1.66 0.20 0.015 0.076 0.18 0.39 50.00 Recleaner Distributions in % Element Fe Si Al Cu PS Ti Mn Magnetite Concentrated Magnetic - 77.96 29.36 44.54 42.54 45.34 16.31 68.14 37.79 84.91 Recleaner Reject No Magnetic - 22.04 70.64 55.46 57.46 54.66 83.69 31.86 62.21 15.09 Recleaner Table 4: Silicate reverse flotation stage (redeaner stage) of the “magnetic concentrate cleaner”. EXAMPLE 5: Obtaining copper and gold concentrate from “non-magnetic cleaner waste”

[0044] Using the "non-magnetic cleaner tailings," a study was conducted to recover copper and gold and generate copper and gold concentrate. The "non-magnetic cleaner tailings" generated in the magnetitic concentrate process route underwent Cu and Au rougher flotation, while the "Cu and Au rougher tailings" then generated underwent Cu and Au scavenger flotation, and the mixture of the copper and gold rougher and scavenger concentrates underwent Cu and Au cleaner flotation. The cleaner tailings are recycled to rougher flotation, and the scavenger tailings are the final rejects. Figure 3 shows the block diagram for obtaining copper and gold concentrate. The flotation conditions (rougher flotation, rougher scavenger, and cleaner from the Cu and Au recovery process route from the non-magnetic cleaner tailings), performed in a DENVER mechanical cell, were: ❖ conditioning times: Amyl Xanthate and Dithiophosphate Collector: 2 minutes and FLOTANOL®M28 and FLOTANOL®D25 (Clariant Sparkling Agent): 1 minute; ❖ flotation time: rougher: 5 minutes, rougher scavenger: 6 minutes and cleaner: 6 minutes; ❖ air flow: rougher and rougher scavenger: 2.0 L / min and cleaner: 1.0 L / min; ❖ impeller rotation: rougher and rougher scavenger: 1000 rpm and cleaner: 700 rpm; ❖ 67.50 g / t of Amyl Xanthate reagent and 27.00 g / t of Dithiophosphate reagent, only collector and reagent dosage in rougher flotation and 18.4 g / t of FLOTANOL®M28 sparkling wine and 33.6 g / t of FLOTANOL®D25 sparkling wine. ❖ without adding depressant; ❖ Natural pH of 10.5, corrected with the addition of lime pulp hydrated 10% m / m.

[0045] Table 5 shows the results. A final product, a Cu and Au cleaner concentrate, with 1.65% Cu and 5.08 g / t Au, was obtained. The mass recovery was 18.47%, and the Cu and Au metallurgical recoveries were 61.85% and 77.56%, respectively. This stage also yields magnetite rougher scavenger tailings (<0.50%), which can be used to obtain additional byproducts for the construction industry, road paving, or as a mineralizer or soil improver due to the presence of silicates in its composition. The non-magnetic recleaner tailings, with a particle size <20 µm and containing Cu and Au, can also be fed to this stage of the process route. Mass of Mass Rec. Mass _ _ Content . . , . „ . . Rec. Rec. . „ Content of Flow D Reieito / de Cu de Au Massa _ de Cu . . ,< .. . ... . . Cu (%) Au (%), a . Au (g / t) Product (kg) (kg) (g) (%) (%) Ahmentation (Reject No. 1989.36 9.81 2.41 100.00 100.00 100.00 0.49 1.21 Magnetic Cleaner) Rougher Reject 2203.59 7.63 1.41 110.77 77.79 58.67 0.35 0.64 Rougher's Scavenger Reject í62i 89 3 740.54 81.53 38.15 22.44 0.23 0.33 (Final Reject) Cleaner Reject 1024.58 5.75 1.29 51.50 58.60 53.43 0.56 1.25 Rougher Concentrate 810.36 7.92 2.28 40.73 80.81 94.76 0.98 2.81 Scavenger Concentrate 581.69 3.89 0.87 29.24 39.64 36.23 0.67 1.50 Cu Cleaner Concentrate 367.47 6.06 1.87 18.47 61.85 77.56 1.65 5.08 Rougher Concentrates + 1392.05 11.81 3.15 69.97 120.44 130.99 0.85 2.26 Scavenger Table 5: Mass and metallurgical balance of copper and gold recovery from non-magnetic cleaner tailings.

Claims

CLAIMS 1. Process for obtaining co-products from copper mining waste, characterized by the fact that it comprises the following steps: a) magnetic separation as a rougher stage, b) ultrafine grinding; c) magnetic separation as a cleaner stage, and d) reverse cationic flotation of silicates as a recleaner stage, in which the copper mining waste consists of the waste generated in the flotation of copper sulfide ores.

2. Process according to claim 1, characterized in that the reject is rougher reject from the flotation of copper sulfide ores.

3. Process according to claim 1 or 2, characterized in that the waste comprises an amount of magnetite in its composition between approximately 5% m / m and approximately 20% m / m.

4. Process according to any one of claims 1 to 3, characterized in that the reject has a Pgo between approximately 106 pm and a top size of 300 pm.

5. Process according to any one of claims 1 to 4, characterized in that the reject is subjected to a preliminary dilution step, before step a), with process water to obtain a pulp with approximately 25% to approximately 35% solids (reject pulp) (2).

6. Process according to any one of claims 1 to 5, characterized in that step a) is carried out in drum-type magnetic separators with rotation between approximately 10 and approximately 30 rpm and with a magnetic field between approximately 600 and approximately 1200 Gauss to obtain the magnetic rougher concentrate (3) and generating the non-magnetic rougher reject (4).

7. Process according to claim 6, characterized in that the magnetic rougher concentrate (3) is subjected to an intermediate classification stage, by means of hydrocyclones, in which fractions smaller and larger than 20 pm are classified.

8. Process according to any one of claims 1 to 7, characterized in that step b) establishes Pgo between approximately 10 pm and 50 pm, preferably Pgo of approximately 20 pm.

9. Process according to claim 6, characterized in that the magnetic rougher concentrate (3) is subjected to intermediate thickening steps, in the presence of flocculant and with a thickening rate ranging from approximately 0.020 m 2 / t / day and about 0.060 m 2 / t / day, followed by dilution with process water to obtain a pulp with approximately 25% to approximately 35% solids (thickened magnetic rougher concentrate pulp) (7).

10. Process according to claim 6, characterized in that the non-magnetic rougher reject (4) is subjected to an integrated route to obtain additional co-products, said route comprising a thickening step, with addition of flocculant and thickening rate ranging from approximately 0.050 m 2 / t / day and about 0.100 m 2 / t / day, and a filtration stage in filter presses or vacuum, with a filtration rate varying between approximately 1000 and approximately 2000 kg / h / m 2 .

11. Process according to any one of claims 1 to 9, characterized in that the thickened magnetic rougher concentrate pulp (7) is fed to step c) conducted in drum-type magnetic separators with rotation between approximately 10 and approximately 30 rpm and with a magnetic field between approximately 600 and approximately 1200 Gauss to obtain the magnetic cleaner concentrate (8) and generating the non-magnetic cleaner reject (9).

12. Process according to claim 11, characterized by the fact that the magnetic cleaner concentrate (8) is subjected to an intermediate dilution step with process water to obtain a pulp with approximately 25% to approximately 35% solids (magnetic cleaner concentrate pulp) (10).

13. Process according to any one of claims 1 to 12, characterized in that the magnetic cleaner concentrate pulp (10) is fed to step d) reverse cationic flotation of silicates, which is carried out with a dosage of approximately 50 to approximately 250 g / t of the FLOTIGAM®17535 collector and a dosage of approximately 5 to approximately 50 g / t of the FLOTANOL®M28 foamer, with a flotation time varying between approximately 5 and approximately 35 minutes, to obtain the recleaner concentrate (sunk) (11) and generating the recleaner reject (floated) (12).

14. Process according to claim 13, characterized in that the recleaner concentrate (11) is subjected to a thickening step, in the presence of flocculant and with a thickening rate between approximately 0.020 m 2 / t / day and about 0.040 m 2 / t / day, followed by a filtration stage in a filter press, with a filtration rate between approximately 1000 and approximately 2000 kg / h / m 2 , to obtain magnetitic concentrate or magnetitic pellet feed.

15. Process according to claim 11, characterized in that the non-magnetic cleaner waste (9) is subjected to an integrated route for obtaining copper and gold concentrate, said route comprising a prior dilution step followed by Cu and Au rougher flotation and Cu and Au cleaner flotation, in which: - dilution is carried out with process water to obtain a pulp with approximately 25% to approximately 35% solids (non-magnetic cleaner reject pulp) (14); - the non-magnetic cleaner reject pulp (14) is fed to the Cu and Au rougher flotation stage with the addition of conventional collectors copper, such as amyl xanthate and / or dithiophosphate; and foaming agent, such as FLOTANOL®M28 and / or FLOTANOL®D25, with flotation time ranging from approximately 5 to approximately 30 minutes and with pulp pH adjustment with the addition of hydrated lime pulp 10% m / m for a pH between 9 and 11; and - the Cu and Au rougher concentrate (15) from the Cu and Au rougher flotation is then subjected to the Cu and Au cleaner flotation stage with a flotation time ranging from approximately 5 to approximately 35 minutes and with pulp pH adjustment with the addition of 10% m / m hydrated lime pulp to a pH between 8 and 12, in which the Cu and Au cleaner concentrate (20) from the Cu and Au cleaner flotation is taken to an additional thickening stage, in the presence of flocculant and with a thickening rate between approximately 0.020 m 2 / t / day and about 0.040 m 2 / t / day, followed by a filtration stage in a filter press, with a filtration rate between approximately 1000 and approximately 1500 kg / h / m 2 .

16. Process according to claim 13 or 15, characterized in that the recleaner reject (12) generated in the reverse cationic flotation step of silicates is added to the non-magnetic cleaner reject pulp stream (14) and fed to the Cu and Au rougher flotation step.

17. Process according to claim 15, characterized in that the Cu and Au rougher waste (16) from the rougher flotation is subjected to a scavenger flotation step with a flotation time ranging from approximately 5 to approximately 10 minutes, with or without the addition of collectors and / or foamers.

18. Process according to claim 17, characterized in that the Cu and Au scavenger concentrate (17) from the scavenger flotation is mixed with the Cu and Au rougher concentrate (15) and fed to the Cu and Au scavenger flotation step.

19. Process according to claim 17, characterized in that the Cu and Au scavenger tailings (18) from the scavenger flotation are subjected to an integrated route to obtain additional co-products, said route comprising a thickening step in the presence of flocculant and with a thickening rate between approximately 0.010 m 2 / t / day and about 0.030 m 2 / t / day, and a filtration stage in a filter press, with a filtration rate between approximately 500 and approximately 1500 kg / h / m 2 .

20. Process according to any one of claims 9, 10, 14, 15 and 19, characterized in that the thickening steps are conducted in the presence of flocculant selected from the group including Flonex 934VHM, Magnafloc 10, Magnafloc 351, Magnafloc 1011, Magnafloc 338 and Praestol Kl 11 -LA.

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