Method for obtaining a nickel ore concentrate, method for processing a nickel ore concentrate, and method for recovering materials derived from nickel ore

Abstract

The present invention relates to a method of recovering materials derived from nickel ore, involving a method for obtaining nickel ore concentrate and a method for processing said concentrate, whereby nickel ore can be processed in an efficient and ecological manner, as well as to the recovery of residues and materials currently untapped from this nickel ore.

Description

Descriptive Report of the Invention Patent for “PROCESS FOR OBTAINING A NICKEL ORE CONCENTRATE, PROCESS FOR PROCESSING A NICKEL ORE CONCENTRATE, AND PROCESS FOR RECOVERING MATERIALS DERIVED FROM NICKEL ORE”.

[0001] The present invention relates to a process for recovering materials derived from nickel from supergene alteration, involving a process for obtaining nickel concentrate and a process for processing said concentrate.

[0002] The present invention allows for ecological and economic gains and advantages, particularly: (i) Allow the recovery of nickel ores and currently unused nickel materials, drastically reducing the disposal of waste into the environment; (ii) Reduction in the use of fossil heating sources, reducing the CO2 emissions typical of this type of process; (iii) Recovery of economically relevant materials, in accordance with the new reality of the circular economy. Description of the State of the Art

[0003] Nickel is a strategic base metal in the construction of stainless steel. It is also a key component in battery technology, along with iron phosphate, and is used in medical equipment, wind turbines, and the production of special steel alloys, among other applications.

[0004] Currently, the nickel market is more than two-thirds related to the production of steel and steel alloys (class II nickel), and less than one-third related to the production of high-purity derivatives with a minimum of 99.0% (class I nickel), the latter being a critical metal in the development of the energy sector, which has energy storage as a bottleneck and has been growing significantly with the change in the matrix. energy from fossil fuel to renewable.

[0005] Known nickel deposits are of lateritic, sulfide, and marine magnesian nodule origin. The latter is abundant but unexploitable, while the former two are raw materials for the production of nickel and nickel alloys.

[0006] Nickel sulfide deposits are derived from volcanic and hydrothermal processes. This type of ore is easily processed by conventional flotation processes because nickel is sulfide. In contrast, nickel sulfide deposits represent approximately 30% to 40% of the world's beneficiable nickel reserves.

[0007] Lateritic nickel ore deposits represent 60% to 70% of the world's reserves, which makes lateritic ores the most important source for beneficiation.

[0008] For practical purposes of grouping for beneficiation, the nickel laterite ore deposit can be divided into 4 zones: zone 1, red laterite, with a lower nickel content (0.5% to 0.8% Ni), zone 2, yellow laterite with a higher nickel content (0.8% to 1.2% Ni), zone 3, transition to saprolite with a higher nickel content (1.2 to more than 2% Ni), and zone 4, saprolite, with nickel contents above 1.5% and a different magnesium and iron composition from zone 3, in general.

[0009] These deposits are subject to various types of beneficiation, including the use of the first three zones in hydrometallurgical beneficiation processes such as high-pressure acid leaching (HPAL) and Caron. Zone 4, the saprolite zone, is used in the pyrometallurgical process for producing ferronickel metal.

[0010] The formation of nickel deposits by lateritization processes involves the combination and interaction of several geological and environmental. It begins with the intrusion and serpentinization of ultramafic bodies, followed by their exposure through tectonic events and / or erosion processes, and subjection to humid tropical climates that promote the development of a deep and strongly weathered regolith. During this phase, nickel is concentrated in goethites and / or smectites in residual form due to the strong dissolution of magnesium and silicon from the primary rock. This is where the ferruginous lateritic levels of red (LV) and yellow (LM) limonite develop. Subsequently, most of the deposits were subjected to tectonic events and climatic changes. Where these changes were minor, the deposits may have been buried, or in more arid climates, they may have reduced weathering and preserved the deposits.When uplift is significant, erosion loss may increase, but under the influence of humid climates and a deeper water table, it is offset by continued weathering and the enrichment of nickel mobilized from the upper portions of the profile in newly formed hydrated magnesium silicates, constituting the deepest layers of mineralized saprolite. This process causes the most mobile ions to remain in solution, enriching the layers of the oxidized deposit with minerals of interest such as nickel and cobalt. These particles precipitate finely and coat the other particles in the deposits, including some rich in nickel and cobalt, such as olivine.

[0011] For better understanding, Figure 1 shows a schematic representation of the lateritic zone, comprising region A1 representing the ferruginous portion near the surface, region A2 representing the oxidized portion (red and yellow limonite), and region A3 representing the saprolitic region. It is noteworthy that the lateritic zone is underutilized or simply ignored by nickel iron producers, being considered below plant feed specifications or unusable. In this sense, Global nickel production is concentrated in 52% of sulfide ore and 48% of lateritic ore. Lateritic ore is primarily used for the production of nickel pig iron (NPI) and nickel ferroalloy, and the portion used for this purpose is found in the saprolite zone.

[0012] Of the world's lateritic ore reserves, only 5% to 8% of the lateritic zone is used for class I nickel production, mainly through the HPAL process.

[0013] It should be noted that currently, the main known processes for beneficiating lateritic nickel ore are Caron and High Pressure Acid Leaching (HPAL) and these are not capable of utilizing the saprolitic zone of the deposit.

[0014] Regarding the Caron process, it becomes economically and environmentally unfavorable as it demands high production and operational costs, in addition to high carbon dioxide (CO2) emissions.

[0015] The commonly used HPAL process can be described in general terms as a high-pressure acid leaching process that uses, in addition to sulfuric acid, high temperatures (around 255 degrees Celsius) and high pressures (around 50 bar or 725 psi) to separate nickel and cobalt from laterite ore.

[0016] This leads to some problems regarding the state of the art in relation to the extraction of nickel from the lateritic zone:

[0017] None of the currently known processes are capable of processing the ferruginous A1 portion (above the oxidized red and yellow limonite portion) of the nickel lateritic zone. This means that the aforementioned ferruginous A1 portion is considered waste by the industry. 1 that operates with the nickel laterite zone, which is simply stored indefinitely (by dry stacking), causing serious ecological problems and high operational losses.

[0018] Furthermore, the A3 saprolite portion of the lateritic zone is currently used only for the extraction of Class II nickel (nickel iron), a low-purity nickel primarily used in stainless steel production. There are currently no known processes for recovering high-purity Class I nickel from the A3 saprolite portion of the nickel lateritic zone, meaning that at least part of this saprolite portion is treated as process waste / tailings by the industry. 2 , which is also merely piled up in post-processing and causes ecological problems and operational losses.

[0019] Furthermore, none of the currently known prior art processes are capable of efficiently extracting other materials of interest from the lateritic zone, being limited to class I or II nickel. It is known that the lateritic zone contains other economically relevant materials (such as magnesium, for example), but these materials cannot be extracted using currently known processes, so they are discarded or piled up after processing as waste / reject.

[0020] It should also be noted that the oxidized A2 portion of the lateritic zone can currently only be processed through processes such as HPAL and CARON for the extraction of nickel and cobalt hydroxide. These processes are not capable of processing the saprolite A3 portion of the lateritic zone. These processes are also not capable of processing nickel portions that are rich in magnesium, as extraction becomes economically unfeasible.

[0021] It is also important to note that there is currently no process capable of extracting materials of interest from both the oxidized A2 and saprolitic A3 portions of the lateritic zone. Studies 3 are currently being carried out in an attempt to apply the “heap leaching” process to the oxidized and saprolytic portions, but this process is extremely costly and operationally inconvenient because it requires the stacking of large quantities of material and the performance of top drip leaching. This process is also incapable of treating the upper A1 ferruginous portion of the lateritic zone.

[0022] In relation to the waste / rejects themselves, it can be seen that the processes known in the state of the art generate at least three types of waste / rejects:

[0023] (A) A first type of residue / reject is the ferruginous portion A1 upper part of the lateritic zone itself, since none of the known processes is capable of operating efficiently on this portion.

[0024] (B) A third type of waste / reject is the remaining materials of interest from the oxidized portion A2 of the lateritic zone, given that currently existing processes (e.g., HPAL, CARON) are not capable of extracting any material from the lateritic zone other than class I nickel. Thus, other materials of economic interest (such as magnesium) are discarded.

[0025] (C) A second type of residue / reject is what remains from the beneficiation of the A3 saprolite portion processed for the production of class II nickel. Since known hydrometallurgy processes are not capable of extracting class I nickel from the saprolite portion of the lateritic zone, the remaining materials of interest from this portion are discarded at the end of the process.

[0026] From the above clarifications, another problem with the state of the art emerges, which is the use of heat from polluting sources such as coal, the burning of which produces CO2, which is known to be harmful to the environment.

[0027] Furthermore, another problem arises from the state of the art, which is the use of sulfuric acid in the recovery process of materials derived from nickel ore, generating a residue. contaminated, unlike the process of this patent.

[0028] Sulfuric acid has low selectivity for leaching in this type of process, and its vapor pressure is relatively low, which makes its regeneration difficult in these processes and requires neutralization and subsequent treatment for its disposal. Bibliography mentioned above

[0029] 1. GUIMARÃES, Carolina das Graças Graciano. Technological Characterization of Lateritic Nickel Ore. Advisor: Leandro Rocha Lemos. 2019. Dissertation (Master's in Metallurgical, Materials and Mining Engineering) - FEDERAL UNIVERSITY OF MINAS GERAIS, [SI], 2019.

[0030] 2. DA COSTA, João Paulo Rodrigues. Characterization of iron-nickel slag for application as rockfill in drainage overtopping dikes. Advisor: Gilberto Fernandes. 2019. Dissertation (Master's in Geotechnics) - Federal University of Ouro Preto, Ouro Perto, 2019.

[0031] 3. OXLEY, Anne et al. Why heap leach nickel laterites?. Minerals Engineering, [SI], p. 1-8, 15 Mar. 2016. Objectives of the Invention

[0032] Thus, a primary objective of the present invention is to provide processes for processing nickel ore, including the saprolite portion, to enable the recovery of marginal ore from ferronickel production mining and currently unused materials from this type of deposit, thus enabling the utilization of this portion of the deposit. Ferronickel producers stock this lateritic portion and primarily utilize the saprolite fraction of the deposit.

[0033] A second objective of the present invention is to provide processes related to the processing of nickel ore that allow the reduction of the use of fossil heating sources, decreasing the CO2 emissions typical of this type of process compared to the state of the art.

[0034] A third objective of the present invention is to provide processes related to nickel ore processing that allow the recovery of economically relevant materials.

[0035] A fourth objective of the present invention is to provide a process for obtaining a nickel ore concentrate that comprises suitable characteristics to allow subsequent high-efficiency chemical beneficiation.

[0036] A fifth objective of the present invention is to provide an improved nickel ore beneficiation process through particular steps that increase the efficiency of the process, starting from a nickel ore concentrate.

[0037] A sixth objective of the present invention is to provide a process for beneficiating a nickel ore concentrate for the recovery of strategic materials, for example, but not exhaustively, iron phosphate (FePÜ4) and nickel and cobalt hydroxide (HNC), or as it is commercially known, Mixed Hydroxide Precipitate (MHP). Brief Description of the Invention

[0038] The present invention relates to a process for obtaining a nickel ore concentrate comprising the steps of: performing intense attrition of the nickel ore; separating the nickel ore by size into at least a fine fraction and a coarse fraction; magnetically separating the coarse fraction to obtain a magnetic fraction; grinding the magnetic fraction to obtain a fine magnetic fraction; and combining the fine fraction and the fine magnetic fraction to obtain a nickel ore concentrate.

[0039] In a possible embodiment of the process of obtaining a nickel ore concentrate, the intense attrition stage is carried out using equipment such as a double rotor mill, rod mill or “scrubber”.

[0040] In another possible embodiment of the process of obtaining a nickel ore concentrate, the intense attrition stage occurs for between 2 and 50 minutes.

[0041] In another possible embodiment of the process of obtaining a nickel ore concentrate, the step of separating by size obtains a fine fraction with a particle size smaller than 75 pm and a coarse fraction with a particle size larger than 75 pm.

[0042] In another possible embodiment of the process of obtaining a nickel ore concentrate, the process comprises a crushing stage carried out until the processed material is below 2” in size.

[0043] The present invention further comprises a process for beneficiating a nickel ore concentrate comprising the steps of mixing a nickel ore concentrate with hydrochloric acid; heating the nickel ore concentrate until achieving a conversion of over 90% of the nickel and cobalt contained in the nickel ore concentrate to their soluble chloride form, and until achieving a desired conversion of the iron, chromium and titanium contained in the nickel ore concentrate to their insoluble oxide form; leaching the nickel ore concentrate with water to solubilize the nickel and cobalt contained in the nickel ore concentrate; and obtaining a liquor loaded with nickel, cobalt, iron and magnesium.

[0044] In one possible embodiment of the beneficiation process of a nickel ore concentrate, the heating step is carried out through microwave irradiation.

[0045] In one possible embodiment of the beneficiation process of a nickel ore concentrate, the leaching step is assisted by microwave irradiation.

[0046] In another possible embodiment of the nickel ore concentrate beneficiation process, the process comprises the step of regenerating the hydrochloric acid used in the first leaching stage by evaporating it in the heating stage, condensing the hydrochloric acid vapor and returning the condensed hydrochloric acid to the leaching stage.

[0047] In another possible embodiment of the beneficiation process of a nickel ore concentrate, the first leaching stage comprises the addition of 0.1 to 5 ml / g of hydrochloric acid per gram of nickel ore concentrate.

[0048] In another possible embodiment of the nickel ore concentrate beneficiation process, the heating step involves heating for a period of 15 to 30 minutes.

[0049] In another possible embodiment of the beneficiation process of a nickel ore concentrate, the second leaching stage comprises microwave irradiation at a temperature between 20°C and 60°C.

[0050] In another possible embodiment of the nickel ore concentrate beneficiation process, the process comprises a liquor filtration step to obtain the insoluble form of oxide containing iron, chromium and titanium.

[0051] In another possible embodiment of the nickel ore concentrate beneficiation process, the process comprises a precipitation step to extract the iron contained in the LI liquor by adding at least one phosphate source in stoichiometric proportion to the liquor.

[0052] In another possible embodiment of the beneficiation process of a nickel ore concentrate, the process comprises the steps of: using MnO2 and KMnO4 to precipitate the manganese by-product of the precipitation step (240) to extract the iron contained in the LI liquor; and precipitate the MHP by adding magnesium oxide.

[0053] In another possible embodiment of the nickel ore concentrate beneficiation process, the process comprises the steps of: adding a solvent to the liquor to obtain a liquor comprising mainly nickel and cobalt; stripping the solvent by adding hydrochloric acid to the liquor; and returning the solvent to the extraction stage.

[0054] In another possible embodiment of the beneficiation process of a nickel ore concentrate, the process comprises the step of adding magnesium oxide to the liquor to obtain nickel and cobalt hydroxide.

[0055] In another possible embodiment of the nickel ore concentrate beneficiation process, the process comprises a pyrohydrolysis stage of the liquor to extract magnesium oxide and hydrochloric acid.

[0056] In another possible embodiment of the beneficiation process of a nickel ore concentrate, the process comprises the steps of: mixing a coarse magnetic fraction rich in chromium with H2O2; and irradiating the mixture through microwaves until the conversion time of over 90% of the chromium phases into sodium chromate.

[0057] The present invention also contemplates a process for recovering nickel ore derivatives that comprises the steps of a process for obtaining a nickel ore concentrate such as the aforementioned in any of its possible embodiments, and also comprises the steps of a process for processing a nickel ore concentrate such as the aforementioned in any of its possible embodiments. Brief Description of the Drawings

[0058] The figures show:

[0059] Figure 1 - is a schematic reproduction of the lateritic zone divided into its ferruginous portions A1, oxidized portion A2 and saprolytic portion A3.

[0060] Figure 2 - is a flowchart of the process of obtaining a nickel ore concentrate according to a possible embodiment of the present invention;

[0061] Figure 3 - is a flowchart of the nickel ore concentrate beneficiation process according to another possible embodiment of the present invention;

[0062] Figure 4 - is a first graph relating the iron recovery (%) obtained by the processes of the present invention correlated with the amount of hydrochloric acid used (in L / kg) and the microwave irradiation time (in minutes); and

[0063] Figure 5 - is a second graph relating the nickel recovery (%) obtained by the processes of the present invention correlated with the amount of hydrochloric acid used (in L / kg) and the microwave irradiation time (in minutes).

[0064] Figure 6 - is a third graph relating the iron recovery (%) obtained by the processes of the present invention correlated with the amount of hydrochloric acid used (in L / kg) and the microwave irradiation time (in minutes).

[0065] Figure 7 - is a fourth graph relating the nickel recovery (%) obtained by the processes of the present invention correlated with the amount of hydrochloric acid used (in L / kg) and the microwave irradiation time (in minutes). Detailed Description of Figures

[0066] First, it should be noted that the term "preferred" used here should not be understood as "imperative" or "mandatory." The term "preferred" is intended to characterize a particularly efficient embodiment of the invention among the many possible ones, with the scope of the invention being limited solely by its characteristics. absolutely essential to obtain the proposed technical effects.

[0067] For the purposes of understanding the present invention, the term “nickel ore” should be understood as any source of nickel, natural or not, pure or pre-processed, that is not sulfide.

[0068] The present invention proposes processes for recovering materials derived from nickel ore, involving obtaining a nickel ore concentrate and processing this concentrate to recover materials of interest.

[0069] Regarding the process of obtaining a nickel ore concentrate, one possible embodiment is described below: PROCESS OF OBTAINING A NICKEL ORE CONCENTRATE

[0070] With regard to obtaining a nickel ore concentrate, the process in question generally comprises, in a possible embodiment, but not imperatively, the steps of:

[0071] - optionally, perform preliminary processing steps 100A;

[0072] - optionally, perform drying, crushing and grinding 100B of nickel ore;

[0073] - perform intense attrition of nickel ore, dry or wet;

[0074] - separate the nickel ore by size 110 into at least a fine fraction FF and a coarse fraction FG;

[0075] - magnetically separate the coarse fraction FG to obtain a magnetic fraction FM,

[0076] - perform attrition 130 of the coarse fraction FG to obtain a fine magnetic fraction FMF; and

[0077] - combine 140 the fine fraction FF and the fine magnetic fraction FMF to obtain a nickel ore concentrate CNL.

[0078] Details of each of these steps will be described below: Preliminary processing steps:

[0079] In a possible embodiment, and optionally, preliminary processing steps 100A can be used, such as feeding the nickel ore into a feeder silo, among other steps necessary for the logistics of preparing said material for subsequent steps. Drying and crushing:

[0080] In one possible and optional embodiment, a 100B drying and crushing step of the nickel ore can be used to obtain particles with a homogeneous grain size, facilitating subsequent beneficiation of the material. Crushing can be performed, for example, in a mineral sizer or cone crusher. Grinding can be performed, for example, in a rod mill or double roller mill. This 100B comminution is preferably performed until the processed material is smaller than 2", but can ideally reach sizes smaller than 1 / 4".

[0081] Subsequently, the ore is ready for an intense attrition stage 100. Intense friction stage:

[0082] The main purpose of the intense attrition stage 100 is to break down the crusts that encapsulate the nickel silicate minerals and the iron-nickel agglomerates of this mining product, thus allowing the obtaining of nickel-containing particles with a large surface area, which is beneficial for the subsequent processing of this material, effectively enriching the nickel content contained in the fine fraction of the nickel ore.

[0083] In other words, the intense attrition stage 100 It advantageously disaggregates the ore particles and cleans them from the surface of the material chemically precipitated by supergenic alteration, essentially composed of goethite. These fine particles, the result of chemical precipitation that had aggregated on the surface of the larger particle and were released by attrition, will concentrate in the finer portion of the ore. This step makes the finer ferruginous portion suitable for leaching and the coarse fraction suitable for magnetic separation, as the mineral surfaces of these coarse particles will be clean. This is a vital point for the high efficiency of the leaching and magnetic separation processes.

[0084] In short, after this cleaning by intense attrition and size separation, the nickel-containing ore particle has a larger surface area, advantageously facilitating its subsequent beneficiation. Furthermore, the coarse fraction is free of these particles, thus enabling its efficient magnetic separation.

[0085] As an example, Tables 1 to 4 below show comparative tests between the increase in attrition time (intense attrition stage 100) and the nickel content of the fine fraction obtained: Tables 1 to 4 - comparisons between the increase in attrition time (5 min., 20 min.) and the nickel content of the fine fraction obtained.

[0086] In the tables above, of the samples that underwent intense attrition 100, all of the oxidized profile separated by zones, named respectively in Table 5 as zone 1, zone 2, zone 3 and zone 4, increased in content with increasing time of exposure to intensive attrition.

[0087] In this sense, intense attrition causes the chemically deposited ferruginous material covering the particles, as well as the nickel-bearing mineral particles covering other particles, to be released and concentrated in a fine fraction (FF). Furthermore, it is worth noting that the concentration of nickel in the fine fraction (FF) due to the removal of fine particles rich in goethite and nickel is also caused by the crystallinity stage of the goethite. The lower the crystallinity (immature and more open crystalline structure), the greater the tendency to absorb Ni into the structure. Therefore, attrition will tend to disaggregate these younger, more friable goethites, which are concentrated in the fines and carry a greater amount of nickel in their structure. In contrast, in the more mature upper levels, where the goethite has undergone several phases of dissolution and recrystallization (aging), it tends to expel nickel from the structure, forming more crystalline and nickel-depleted goethites.

[0088] Observing the nickel distribution in all fractions tested, an increase in the fine fraction FF was observed with increasing exposure time to the intense attrition equipment. The table below shows the mineralogical composition of the nickel ore after 20 minutes of attrition in the fine fraction, where a considerable concentration of goethite containing iron and nickel can be observed: Table 5 - Mineralogical composition of nickel ore after 20 minutes of attrition

[0089] Preferably, intense attrition 100 with shear force should occur for between 2 and 50 minutes, more preferably between 10 and 25 minutes. Said intense attrition 100 may occur in equipment such as a double rotor mill, rod mill, or scrubber.

[0090] After intense attrition 100, the process moves on to a size separation step 110, as follows. Size separation step:

[0091] The size separation step 110 aims to perform a granulometric cut in the material that has undergone intense attrition 100, to allow separating the material into fine FF and coarse FG fractions, and subsequently separate a magnetic fraction FM from the coarse FG fraction of the material, aiming to obtain magnetic fractions for subsequent chemical treatment and non-magnetic fractions rich in PGM and rare earths.

[0092] More specifically, the size separation step 110 is preferably performed using an aerocyclone or hydrocyclone, depending on whether the processing is dry or wet. This size separation equipment is configured to separate the fine fraction (FF) from the coarse fraction (FG) of the feed material. Preferably, the separation performed in the cyclone separates the material into a fine fraction (FF) with a size smaller than 75 pm, preferably smaller than 30 pm, and more preferably smaller than 20 pm, and into a coarse fraction (FG) with a size larger than 75 pm, preferably larger than 30 pm, and most preferably larger than 20 pm.

[0093] Once the fine FF and coarse FG fractions of the material have been separated, the fine FF fraction is separated for subsequent chemical processing, and the coarse FG fraction proceeds to the magnetic separation stage, as follows. Magnetic separation step:

[0094] The magnetic separation step 120 aims to separate a magnetic fraction FM from the coarse fraction FG obtained in the size separation step 110, to allow subsequent chemical processing of said magnetic fraction FM extracted from the coarse fraction FG together with the fine fraction FF extracted in the size separation step 110.

[0095] This magnetic separation is preferably carried out by a magnetic separator, such as Metso or Outotec.

[0096] The non-magnetic FNM fraction extracted by the magnetic separator is removed from this process. However, it is important to note that this non-magnetic FNM fraction is mostly silicates, but may also include PGMs (gold, silver, and platinum group metals) and rare earths, which advantageously have the potential for beneficiation through parallel processes.

[0097] The magnetic fraction FM extracted from the coarse fraction FG by the magnetic separator, in turn, goes to an attrition stage 130, as follows. Magnetic fraction grinding stage:

[0098] The magnetic fraction FM extracted in the magnetic separation step 120 is directed to a comminution equipment, such as a ball mill, for passing through a grinding step 130 below 150 pm, more preferably 75 pm, and may be, even more preferably, below 20 pm.

[0099] This step aims to reduce the particle size of the magnetic fraction FM, preferably to a size smaller than 20 pm, in line with the fraction FF obtained in the intense attrition step 100, thus obtaining a fine magnetic fraction FMF for its subsequent combination with the fine fraction FF obtained in the separation by size step 110.

[0100] Once the fine magnetic fraction FMF has been obtained, the stage of combining it with the fine fraction FF begins, as follows.

[0101] The magnetic fraction, if rich in Cr2O3 from chromite or hercynite, can be further processed using microwave irradiation. In this case, the coarse, chromium-rich magnetic fraction is mixed with 100 to 200% m / m at the stoichiometric ratio of NaOH, preferably between 110 and 150% m / m, more preferably still between 125 and 135% m / m together with amounts of 100 to 200% m / m of the stoichiometry with respect to the chromium of H2O2, more preferably between 150 and 180% m / m taking to the microwave until the conversion time above 90% of the chromium phases in sodium chromate, preferably for a time between 2 to 15 minutes, and more preferably for a time between 3 to 5 minutes, following the equations below: Cr2O3+ 4NaOH + 3H2O2+ Microwave - 2Na2CrO4+ H2O

[0102] The sodium chromate in solution can then be filtered and separated from the rest of the coarse magnetic fraction. Step of combining the fine magnetic fraction with the fine fraction:

[0103] In this combination step 140, the fine magnetic fraction FMF is added to the fine fraction FF to form a final mass, hereinafter referred to as “nickel ore concentrate” CNL, which can be chemically processed, as we will see later.

[0104] The joining of the two fine fractions FF and fine magnetic FMF can be carried out by any suitable means, including simple mechanical mixing of both.

[0105] Furthermore, the aforementioned nickel ore concentrate comprises approximately 60% of the initial nickel ore volume, which in itself already implies high efficiency in separating the material that is effectively of interest for subsequent processing, even disregarding the non-magnetic fraction removed from the process, which may even be used later in other processes as it may possibly contain other materials of parallel interest.

[0106] In accordance with the above, the process of obtaining a nickel ore concentrate proposed here advantageously results in a nickel ore concentrate in which the nickel-enriched ore particle has a greater surface area, since the goethite (FeO(OH)) and hematite (Fe2O3) and other nickel-bearing minerals have been mostly disaggregated from the ore particles, which ensures a nickel ore concentrate particularly desirable for subsequent high-efficiency chemical beneficiation.

[0107] Having presented a possible embodiment of the process for obtaining nickel ore concentrate CNL, the present invention also relates to a process for processing nickel ore concentrate to obtain derivatives of interest, which will be detailed in more detail below. NICKEL ORE CONCENTRATE BENEFICIATION PROCESS

[0108] With regard to the processing of a nickel ore concentrate to obtain a charged LI liquor, the process in question generally comprises, in a possible embodiment, but not imperatively, the steps of:

[0109] - mix 200 um of nickel ore concentrate CNL with hydrochloric acid;

[0110] - heat or irradiate 210 the nickel ore concentrate CNL until a desired conversion of the nickel and cobalt contained in the nickel ore concentrate to their soluble chloride form is achieved, and until a desired conversion of the iron, chromium and titanium contained in the nickel ore concentrate to their insoluble oxide form is achieved;

[0111] - optionally, regenerate 210A the hydrochloric acid used in the previous leaching step 200 by evaporating it in the heating or irradiation step 210 and condensing it thereafter, and returning the hydrochloric acid to the leaching step 200; and

[0112] - leach 220 with water the nickel ore concentrate CNL for solubilization of nickel and cobalt contained in the CNL nickel ore concentrate, optionally with leaching assisted by microwave irradiation; and

[0113] - obtain 230 a loaded LI liquor, mainly of nickel, cobalt, iron, manganese and magnesium.

[0114] The above steps will be described in detail below. Step of mixing nickel ore concentrate with hydrochloric acid

[0115] Mixing step 200 involves mixing a nickel ore concentrate with hydrochloric acid, for example, in a ribbon blender, pug mill, or any equipment that mixes liquid and solid equally.

[0116] It is very important to emphasize that the use of hydrochloric acid applied to mix a nickel ore concentrate is more efficient and more advantageous than the use of sulfuric acid commonly used in the state of the art, at least for the following reasons: (i) The mixing process proposed here requires a smaller amount of hydrochloric acid for the preparation of the hydrochloric acid concentrate compared to the other processes; and (ii) Hydrochloric acid has a vapor pressure relatively higher than the vapor pressure of sulfuric acid, which, for the process proposed here, is beneficial as it allows for the facilitated regeneration of hydrochloric acid and its use in a cyclical manner, as will be seen later.

[0117] Preferably, an amount of 0.1 ml / g to 5 ml / g of hydrochloric acid per gram of worked material, more preferably 0.8 to 2.0 ml / g, is added to the nickel ore concentrate.

[0118] After mixing 200, the heating or irradiation step 210 of the concentrate follows, as follows. Heating stage

[0119] Once the mixture 200 is made, a mass of nickel ore concentrate is obtained, specifically in this case, which is sent to a device for heating or irradiation 210 of the Material. Heating can be achieved by irradiation, convection, induction, heat conduction, or any other suitable heating method. Microwave irradiation is preferred. However, other devices can be used, such as infrared devices or radio induction.

[0120] This heating process converts the nickel and cobalt in the nickel ore concentrate into their soluble chloride form, and the iron, chromium, and titanium in the nickel ore concentrate into their insoluble oxide form. The conversion occurs according to the following equation: Or even by the mechanisms, FeOOH( SÓlido) + O2+ Energy -> 2 e20 3(sózído) + 2H2O

[0121] Therefore, said heating or irradiation 210 should be carried out until the desired conversion levels of the nickel and cobalt contained in the nickel ore concentrate to their soluble chloride form are reached (e.g., above 90%), and until the desired conversion levels of the iron, chromium, and titanium contained in the nickel ore concentrate to their insoluble oxide form are reached. By way of example, in a configuration utilizing microwave irradiation, said heating or irradiation 210 may occur, for example, for 5 to 50 minutes, more preferably for 10 to 30 minutes, or until the entire mixture reaches 150 to 200 degrees Celsius and maintained for about 5 to 40 minutes, preferably for 15 to 30 minutes, preferably for 20 minutes.

[0122] It should be noted that heating or irradiation 210 is preferably carried out in such a way as to transfer energy, rather than heat, to the material, such that said heating vibrates each of the minerals contained in the material at a specific frequency, which depends on the dielectric constant of each mineral. This transfer of energy in the form of vibration causes a phase change in the ore.

[0123] Likewise, goethite, when subjected to the action of, for example, irradiation, in the presence of oxygen, transforms into hematite, so that this structural transformation takes nickel to the surface of the mineral, making the nickel, advantageously, more susceptible to subsequent leaching.

[0124] It is also important to note that, despite the preferred times described above for the heating or irradiation step 210 described herein, the heating time used to transfer energy to the nickel ore substantially influences the subsequent stages of beneficiation of the nickel ore concentrate, particularly for the recovery of iron and nickel. The crystalline structures of nickel- and cobalt-bearing minerals, such as goethite and olivine, which will be ground to expose the nickel, have an open atomic structure, which allows the penetration of hydrochloric acid.Penetrability can be amplified by electromagnetic waves radiated via microwaves, for example, leaching nickel and cobalt from these structures forming a stable chloride, while the leached iron portion forms an unstable chloride that will quickly convert into the form of insoluble hematite and the portion of iron not leached by hydrochloric acid reacts with oxygen in the air also forming insoluble hematite.

[0125] To illustrate this issue, figures 4 and 5 reveal graphs that correlate the microwave irradiation time (Microwave Time (min.)), the amount of acid (Hydrochloric Acid (L / kg)) used in the leaching step 200 and the percentage of material recovered from nickel ore concentrate in subsequent beneficiation stages, iron (Iron Recovery (%)) and nickel (Nickel Recovery (%)), respectively.

[0126] Figure 4 shows that the longer nickel ore is irradiated, the less iron is recovered in the subsequent beneficiation process. In contrast, Figure 5 indicates that the longer nickel ore is irradiated with microwaves, the more nickel is recovered.

[0127] Therefore, it becomes clear that the heating or irradiation time 210 must take into account the element of interest to be removed, or even find a balance between both, depending on the desired application.

[0128] To further illustrate this possibility, Figures 6 and 7 also show the selectivity of the nickel recovery process for the main contaminant in the liquor: iron. In addition to selectivity, the amount of iron solubilized can be controlled through the microwave irradiation time and acid concentration used, bringing unique versatility to the process. For example, in a time of 20 minutes and a concentration of 2 liters of acid per kilogram of sample, nickel recoveries of nearly 100% are achieved, while iron recoveries are virtually zero. Furthermore, the iron present in the liquor will be precipitated as phosphate and thus become a byproduct of nickel and cobalt production.

[0129] That said, the preferred (but not mandatory) use of microwaves for irradiating nickel ore at this stage brings a number of advantages to the nickel ore concentrate production process, as well as to the nickel ore beneficiation process as a whole. Some of these advantages are described below, but are not exhaustive: (i) Through microwave radiation, it is possible to control adequately solubilize iron and, in this way, allow control of the elements to be extracted from nickel ore, as already explained above. (ii) By using microwave irradiation, a high conversion of nickel and cobalt is obtained (above 85%), and this level of conversion is not achievable by conventional furnaces. (iii) Microwaves allow the conversion of elements contained in nickel ore at ambient pressure, while state-of-the-art methods (e.g., the HPAL method) work at high pressures to achieve lower efficiencies and selectivity. (iv) The use of microwaves allows the regeneration of hydrochloric acid used in the processing of nickel ore concentrate, as will be seen later, because this acid is extremely susceptible to microwaves and has a very high vapor pressure.

[0130] In any case, it should be noted that the use of irradiation, even through microwaves, is not imperative for carrying out the present process, so that, as previously exemplified, other forms of heating can be used.

[0131] Once this first heating or irradiation 210 has been carried out, the optional step of regenerating the hydrochloric acid used in the immediately preceding mixing step 200 is carried out. Hydrochloric acid regeneration step

[0132] After the aforementioned heating or irradiation 210, about 20% to 90% of the hydrochloric acid from the mixture 200 remains in the material, while the other 80% to 10% is evaporated, depending on the residence time, due to the high vapor pressure of the hydrochloric acid.

[0133] Considering that the present process proposed here works at ambient pressure, this allows the hydrochloric acid to evaporate and be easily captured and condensed for regeneration.

[0134] In this way, in a possible and optional embodiment of the present process, it is possible to advantageously carry out a regeneration step 210A of the hydrochloric acid, involving the capture of the acid vapor generated in the heating 210 and its subsequent condensation, and subsequent direction or return of this acid to the mixing step 200.

[0135] In other words, through this possible embodiment of the present invention, a large part of the hydrochloric acid used is regenerated and recirculated, thus obtaining an efficient process with low consumption of hydrochloric acid for the mixture 200.

[0136] Whether or not this hydrochloric acid regeneration stage is carried out, a leaching stage 220 is carried out, as follows. Microwave-assisted leaching step

[0137] After the heating or irradiation step 210, followed or not by the regeneration of hydrochloric acid, the nickel ore concentrate undergoes leaching 220, which may be assisted or supplemented by simultaneous microwave irradiation.

[0138] Said leaching step 220 consists of mixing the irradiated nickel ore concentrate from the previous heating or irradiation step 210 with water to solubilize the nickel and cobalt present within the concentrate. Additionally, microwave irradiation may be used in this leaching step 220 to accelerate the leaching process in some specific applications. In this case, the irradiation performed in this step is preferably carried out at low temperatures, more preferably between 20 and 100°C, and most preferably between 30 and 50°C.

[0139] It should be noted that the microwave irradiation that assists this 220 leaching is optional and not mandatory, being desirable depending on the type of application. Furthermore, this irradiation step simultaneous to 220 leaching should not be confused with the heating step or irradiation 210 immediately preceding.

[0140] Through this leaching stage 220, whether assisted or not by microwave irradiation, a nickel ore concentrate is obtained to obtain an LI liquor loaded with nickel, cobalt, iron, manganese and magnesium, which contains materials of interest for subsequent processing and extraction of these materials from the LI liquor.

[0141] Advantageously, the present invention solves the problem of using heat from polluting sources such as coal, the burning of which produces CO2, which is known to be harmful to the environment, while at the same time using hydrochloric acid and not sulfuric acid, with hydrochloric acid providing greater nickel recoveries through a smaller amount of acid used, achieving recoveries above 90% at a ratio of 1.125:1 ml / g.

[0142] Additionally, in the preferred embodiment, the present nickel ore concentrate beneficiation process allows leaching to be carried out at ambient pressure due to microwave irradiation, unlike, for example, the HPAL process of the prior art.

[0143] For clarification, the HPAL process, as previously explained, requires high temperatures to convert nickel ore. This requires heating at high pressures, not only to achieve the required high temperatures but also to keep the iron insoluble in the HPAL process. The process of the present invention, in its preferred embodiment, using microwave irradiation, does not require high temperatures or high pressures and can be performed at ambient pressure.

[0144] As an example, the tables below show liquor recovery tests under different conditions. The first table (Table 6) indicates the compositions tested, and the second table (Table 7) indicates the recovery results obtained in the tests. Table 6 - compositions of the tested liqueurs. Table 7 - recoveries obtained from the tests.

[0145] The "Test" column in the tables above indicates the tests performed with different liquor compositions. The line referring to "theoretical liquor" is hypothetical, assuming that the entire nickel ore content had been solubilized. The lines indicating the numbers 001 to 011 refer to the liquor contents tested after the conversion step, in this case with a microwave, and with microwave time in minutes, hydrochloric acid content in liters per kilogram, and leaching with water.

[0146] Comparing process liquor 004 with process liquor 006, for example, it is possible to see that microwave time changes iron solubilization drastically, iron recovery drops from 63.685% for process liquor 004 to 5.022% for process liquor 006, while maintaining high nickel and cobalt recovery.

[0147] In another example, process liquor 009 has high nickel and cobalt recoveries and low iron recovery, resulting in a liquor free of contaminants. Higher contents, such as silicon, can be removed, for example, through filtration with diatomaceous earth, and the other contaminant, manganese, can be separated by precipitation and filtration at pH 7, producing a liquor rich only in nickel and cobalt.

[0148] Once the LI liquor loaded with materials of interest has been obtained, it is possible to extract these materials of interest from said liquor through a series of additional steps, which will be explained below. Co-product filtration step (oxide containing iron, chromium and titanium)

[0149] From obtaining the LI liquor, one can, in a possible embodiment, carry out a filtration 230 in which said liquor is Extracting the insoluble form of oxide containing iron, chromium, and titanium is thickened, filtered, and separated from the charged liquor. This filtration can be performed by a filter press, for example, and generates a first byproduct, CO, containing mainly iron oxide (Fe2O3), silicon dioxide (SiO2), and chromium oxide (Cr2O3). This can be separated and further processed later, if obtaining these materials is desired. It should be noted that, naturally, the extracted insoluble form may contain other materials in lower levels, but mainly contains oxide containing iron, chromium, and titanium. Iron phosphate precipitation and filtration steps

[0150] Following filtration step 230, a precipitation step 240 may be performed to extract the iron contained in the LI liquor. For this purpose, for example, a precipitation tank is used, and the LI liquor is added to it along with phosphate sources (e.g., phosphoric acid, sodium phosphate, ammonium phosphate, among others) in a stoichiometric proportion, to force the selective precipitation of the iron contained in the LI liquor in the form of iron phosphate. It is optional to use iron phosphate as a seed to facilitate its precipitation.

[0151] Regarding the steps involved in obtaining iron phosphate, it is important to note that iron is one of the most significant interfering factors and can be a byproduct depending on the form in which it is precipitated. For example, iron phosphate (FePÜ4) is insoluble in hydrochloric acid at low pH.

[0152] It is noteworthy that nickel remains solubilized over a wide pH range, from 0 to 7, and above that it precipitates in the form of nickel hydroxide, mainly at pH 9. Iron, on the other hand, precipitates in the form of phosphate from pH 1.8 and remains in the solid phase at high pH. Due to this difference in precipitation conditions observed between nickel and iron, it is possible to selectively precipitate iron in the form of phosphate, which is a value-added product.

[0153] In this sense, precipitation occurs preferentially with 200% of the stoichiometric ratio of hydrogen peroxide and 150% of the stoichiometric ratio of phosphoric acid in relation to Fe ions that are in solution.

[0154] The excess is used to increase the pH of the solution to maintain the iron phosphate in the solid phase. In this context, for example, after 2 hours of precipitation at 80°C, a precipitation of over 97% is advantageously obtained, with a content of over 95% iron phosphate without coprecipitation of nickel and cobalt.

[0155] Furthermore, it was observed that the LI liquor, after precipitation with phosphoric acid (H3PO4), takes on a blue-green hue, resulting from the nickel and cobalt ions in solution. Iron phosphate (FePÜ4) forms a white, high-purity precipitate.

[0156] That said, once the iron phosphate has been precipitated, the LI liquor or part of it containing the precipitated iron phosphate is passed through a filter press to filter the iron phosphate, thus obtaining the said iron phosphate as the product of interest.

[0157] Purification step by precipitation extraction.

[0158] After the iron removal step in phosphate precipitation, the main contaminants in the solution are manganese and magnesium. Manganese can precipitate along with nickel and cobalt if left in solution, requiring a liquor purification step such as solvent extraction or selective manganese precipitation. Magnesium does not precipitate along with MHP, so the liquor does not need to have a low magnesium concentration.

[0159] Manganese can be precipitated subsequently to iron, using MnO2 as a precipitating agent, KMnO4 at a concentration between 0.2mol / L and 2 mol / L, preferably between 0.4 and 0.6 mol / L at a temperature between 10 and 40°C, more preferably between 20 and 35°C for 30 to 120 minutes, preferably 60 to 90 minutes, under agitation. After removing and filtering the solids from these two main coproducts, iron in the form of phosphate and manganese in the form of oxide, the MHP can be precipitated by adding magnesium oxide until the pH is between 5 and 10, preferably between 6 and 8. The precipitated MHP should be filtered, and the magnesium-rich solution sent to a spray roaster to regenerate the hydrochloric acid and precipitate the magnesium oxide, which was in solution as chloride. Solvent extraction and solvent stripping steps

[0160] After the iron phosphate precipitation steps 240 and filtration 241 of the LI liquor, a purification step of the LI liquor can be performed by extracting certain materials from it using solvent (e.g., magnesium and iron residues from the previous steps), aiming to maintain only nickel and cobalt in the LI liquor. To this end, a solvent (e.g., Cyanex 301) is added to the LI liquor, preferably in a ratio of two parts organic phase to one part liquid, with a contact time of 5 to 50 minutes, preferably 20 to 40 minutes, preferably 30 minutes, at a temperature of 10 to 80 degrees, more preferably 20 to 40 degrees, most preferably at 30 degrees. The extraction steps take place in countercurrent, preferably in 1 to 6 steps, more preferably in 2 to 4 steps, most preferably in 3 steps, and can occur in both intensive mixing tanks and pulsating columns.

[0161] Subsequently, solvent stripping 251 is performed by adding hydrochloric acid to the LI liquor, preferably 0.5 parts of hydrochloric acid at a concentration of 10 mol / L for each part of organic matter. The solvent SO is returned to extraction step 250, and the purified LI liquor, containing mainly nickel and cobalt, is obtained.

[0162] With regard to the steps listed above, solvent extraction is a liquid-liquid extraction technique that uses the immiscibility of the phases to transfer mass from the aqueous phase, the LI liquor, to the organic phase.

[0163] Preferably, the solvent used is Cyanex 301, an extractant with the organic function of thio-phosphate and has high selectivity for the extraction of nickel and cobalt.

[0164] For example, for the condition of 2 mol / L of Cyanex 301 in isoparaffin at a temperature of 50°C and a natural pH of 1.8, after three extraction stages under these conditions, 97% extraction of nickel ions was obtained. After two extraction stages under these conditions, 99% extraction of cobalt ions was obtained.

[0165] Still by way of example, the above conditions were observed for stripping the organic phase loaded with nickel and cobalt with a residence time of 10 to 50 minutes, preferably 20 to 40 minutes, more preferably 30 minutes of extraction for desorption with hydrochloric acid at a concentration preferably of 1 to 10 mol / L, preferably 2 to 6 mol / L, more preferably 3 mol / L at a temperature preferably of 20 to 60°C, more preferably of 30 to 40°C with an aqueous organic ratio of preferably (O:A) 1:0.5 to 1:5, more preferably (O:A) of 1:1 to 1:3, most preferably a ratio (O:A) of 1:2. It was observed that solvent extraction generates an acidic phase rich in nickel and cobalt. Nickel and cobalt precipitation stages

[0166] Once the LI liquor rich in nickel and cobalt has been obtained, to extract these materials of interest from the liquor, magnesium oxide (calcined magnesia) is added to the LI liquor in a precipitation tank.

[0167] Preferably, magnesium oxide is added until the pH of the solution reaches nine, and then precipitation occurs. The product of the precipitation that occurs under these conditions is nickel hydroxide and cobalt HNC, which can be extracted from the LI liquor, for example, through filter press filtration. For example, precipitation with magnesium oxide (MgO) can be performed by adding 0.1 to 1 kilogram of magnesium oxide per kilogram of the nickel-cobalt mixture in solution for 1 to 5 hours, more preferably 2 to 4 hours, and most preferably 3 hours, at a temperature of 20 to 80°C, more preferably 30 to 60°C, and most preferably 40°C. Advantageously, it was observed that both nickel and cobalt precipitated above 99%. After this precipitation step with magnesium oxide, a decantation and filtration step can be performed to obtain this nickel and cobalt hydroxide precipitate.

[0168] It is worth noting that nickel and cobalt hydroxide is a product that is widely used in the battery industry, however, if desired, new separation steps can be used to obtain nickel and cobalt in their individual forms and subsequent reduction to electrolytic metallic form.

[0169] Such steps may involve, for example, the separation of nickel and cobalt through solvent separation, followed by the extraction of nickel and cobalt through electrolysis. It should also be noted that the nickel obtained through the process described here is high-purity nickel, i.e., Class I nickel. Pyrohydrolysis steps for extraction or regeneration

[0170] After extraction of nickel and cobalt hydroxide from the LI liquor, said liquor contains residual magnesium chloride and hydrochloric acid. If extraction or regeneration of these elements is desired, a pyrohydrolysis step 270 of said LI liquor can be adopted, preferably using a Spray Roaster or similar equipment.

[0171] The magnesium oxide inserted into the liquor in previous steps is precipitated and the hydrochloric acid is also extracted, allowing the regeneration and reuse of both, including in the aforementioned steps of process described here.

[0172] Thus, advantageously, this embodiment of the process of the present invention differs from the state of the art also by providing a regeneration of both magnesium oxide and hydrochloric acid, thus obtaining a circulating charge.

[0173] Having presented the processes for obtaining a nickel ore concentrate and for processing a nickel ore concentrate, it becomes clear that a process for recovering materials of interest from nickel ore can be obtained by combining both processes in a continuous process, if this is desirable.

[0174] Furthermore, it also makes clear that the processes proposed here can bring numerous economic and ecological benefits to the recovery of materials of interest from nickel ore. The following advantages can be cited, but are not exhaustive: (A) Allow the recovery of waste and materials currently unused from this nickel ore, thus allowing the removal of this waste from nature; (B) Elimination of the use of fossil fuel heating sources, reducing the CO2 emissions typical of this type of process; and (C) Recovery of economically relevant materials.

[0175] More particularly, the advantages observed by the use of the present invention, in a non-exhaustive manner, are: (I) Highly efficient nickel ore beneficiation, given that this type of deposit was largely ignored by the industry due to the lack of efficiency of existing recovery processes; (II) Recovery of multiple by-products from nickel ore; (III) Control of the solubility of iron in nickel ore and, consequently, control of the by-products to be extracted; (IV) Elimination of the need to convert ore elements nickel through furnaces, completely eliminating the emission of polluting gases from the process; (V) Use of hydrochloric acid, which has greater leaching efficiency and has a higher vapor pressure than sulfuric acid, which allows for greater process efficiency and the possibility of regeneration; and (VI) Possibility, in some embodiments, of saving on the amount of material used due to the possibility of regenerating hydrochloric acid and manganese oxide.

[0176] Having described a preferred embodiment, it should be understood that the scope of the present invention encompasses other possible variations, being limited only by the content of the appended claims, including possible equivalents.

Claims

CLAIMS 1. Process for obtaining a nickel ore concentrate, characterized by the fact that the process comprises the following steps: - perform intense attrition (100) of nickel ore; - separate by size (110) the nickel ore into at least one fine fraction (FF) and one coarse fraction (FG); - magnetically separate (120) the coarse fraction (FG) to obtain a magnetic fraction (FM); - perform grinding (130) of the magnetic fraction (FM) to obtain a fine magnetic fraction (FMF); and - combine (140) the fine fraction (FF) and the fine magnetic fraction (FMF) to obtain a nickel ore concentrate (CNL).

2. Process for obtaining a nickel ore concentrate, according to claim 1, characterized in that the intense attrition step (100) is carried out using equipment of the double rotor mill, rod mill or "scrubber" type.

3. Process for obtaining a nickel ore concentrate, according to claim 1, characterized in that the intense attrition step (100) occurs for between 2 and 50 minutes.

4. Process for obtaining a nickel ore concentrate, according to claim 1, characterized in that the size separation step (110) obtains a fine fraction (FF) with a particle size smaller than 75 µm and a coarse fraction (FG) with a particle size larger than 75 µm.

5. Process for obtaining a nickel ore concentrate, according to claim 1, characterized in that it comprises a crushing step (100B) carried out until the processed material is below 2” in size.

6. Process for beneficiating a concentrate of Nickel ore characterized by the fact that it comprises the following steps: - mix (200) a nickel ore concentrate (CNL) with hydrochloric acid, - irradiate (210), by microwaves, the nickel ore concentrate (CNL) until a conversion of over 90% of the nickel and cobalt contained in the nickel ore concentrate to their soluble chloride form is achieved, and until a desired conversion of the iron, chromium and titanium contained in the nickel ore concentrate to their insoluble oxide form is achieved; - leach (220) the nickel ore concentrate (CNL) with water to solubilize the nickel and cobalt contained in the nickel ore concentrate (CNL); and - obtain (230) a liquor (LI) loaded with nickel, cobalt, iron and magnesium.

7. Beneficiation process of a nickel ore concentrate, according to claim 6, characterized in that the leaching step (220) is assisted by microwave irradiation.

8. Process for beneficiating a nickel ore concentrate, according to claim 6, characterized in that it comprises the step of regenerating (210A) the hydrochloric acid used in the first leaching step (200) by evaporating it in the heating step (210), condensing the hydrochloric acid vapor and returning the condensed hydrochloric acid to the leaching step (200).

9. Beneficiation process of a nickel ore concentrate, according to claim 6, characterized in that the first leaching step (200) comprises adding 0.1 to 5 ml / g of hydrochloric acid per gram of nickel ore concentrate.

10. Process for beneficiating a concentrate of nickel ore, according to claim 6, characterized in that the heating step (210) comprises heating for a period of 5 to 50 minutes.

11. Beneficiation process of a nickel ore concentrate, according to claim 6, characterized in that the second leaching stage (220) comprises microwave irradiation at a temperature between 20°C and 100°C.

12. Beneficiation process of a nickel ore concentrate, according to claim 6, characterized in that it comprises a filtration step (230) of the liquor (LI) to obtain the insoluble oxide form containing iron, chromium and titanium.

13. Beneficiation process of a nickel ore concentrate, according to claim 6, characterized in that it comprises a precipitation step (240) for extracting the iron contained in the liquor LI by adding at least one phosphate source in stoichiometric proportion to the liquor (LI).

14. A process for beneficiating a nickel ore concentrate, according to claim 13, characterized in that it comprises the steps of: - Use MnO2 and KMnO4 to precipitate the manganese byproduct of the precipitation step (240) for extracting the iron contained in the LI liquor, - Precipitate MHP by adding magnesium oxide.

15. A process for beneficiating a nickel ore concentrate, according to claim 6, characterized in that it comprises the following steps: - add (250) a solvent (SO) to the liquor (LI) to obtain a liquor (LI) comprising mainly nickel and cobalt; - perform "stripping" (251) of the solvent (SO) by adding hydrochloric acid to the liquor (LI); and - return the solvent (SO) to the extraction step (250).

16. Beneficiation process of a nickel ore concentrate, according to claim 15, characterized in that it comprises the pyrohydrolysis step (270) of the liquor (LI) for extraction of magnesium oxide and hydrochloric acid.

17. Process for beneficiating a nickel ore concentrate, according to claim 6, characterized in that it comprises the step of adding (340) magnesium oxide to the liquor (LI) to obtain nickel cobalt hydroxide (HNC).

18. A process for beneficiating a nickel ore concentrate, according to claim 6, characterized in that it comprises the following steps: - mix a coarse, chromium-rich magnetic fraction with H2O2; and - Irradiate the mixture using microwaves until the conversion time exceeds 90% of the chromium phases into sodium chromate.

19. A process for recovering nickel ore by-products, characterized in that it comprises the steps of a process for obtaining a nickel ore concentrate, as defined in any one of claims 1 to 5, and further comprises the steps of a process for beneficiating a nickel ore concentrate as defined in any one of claims 6 to 18.

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