PROCESS FOR THE DEPRESSION OF IRON SULFIDES AND OTHER WASTE ELEMENTS IN THE CONCENTRATION OF ORE BY FLOTATION AND ELECTROCHEMICAL REACTOR.

Abstract

Process for the depression of iron sulfides and other waste elements in mineral concentration by flotation and electrochemical reactor. The proposed invention represents a method based on the action of electrodes on the mineral, which can replace, complement, or minimize the consumption of chemical reagents, as well as improve their effect.

Description

PROCESS FOR THE DEPRESSION OF IRON SULFIDES AND OTHERS ELEMENTS TO DISCARD IN THE MINERAL CONCENTRATION BY FLOTATION AND ELECTROCHEMICAL REACTOR FIELD OF INVENTION The present invention relates to a process for the depression of iron sulfides and other waste materials, primarily pyrite, but not exclusively, in mineral concentration by flotation. It also relates to an electrochemical reactor. This process, as well as the reactor, replaces, minimizes, optimizes, or complements the use of depressants and other chemical reagents during the depression of iron sulfides and other waste materials such as arsenic, antimony, dismuth, mercury, and lead. This invention is particularly relevant for the flotation of sulfide minerals of all types. The field of the invention is primarily applicable to nickel, copper, zinc, and lead ores. BACKGROUND OF THE INVENTION Flotation is used to concentrate or separate mineral species by selectively adhering mineral particles of each species to air bubbles. These bubbles float to the surface of the liquid. forming foams that are collected as the product of said process. The adhesion of particles to bubbles occurs primarily based on the hydrophobicity of the mineral surface. More hydrophobic particles tend to adhere to the bubbles, and therefore float. While the more hydrophilic ones tend to be surrounded by liquid, causing them to sink. To modulate the hydrophobicity and consequent buoyancy of the different Mineral species, typically chemical reagents are added, such as collectors, depressants, activators, inhibitors, foamers or modifiers

[11] . In the flotation of sulfides, for example, nickel, copper, zinc, and lead ores, a primary objective in concentrating the mineral(s) of interest is the selective depression of pyrite (an iron-sulfur ore), since it is rarely profitable to trade the iron. Furthermore, pyrite and other sulfides may be associated with or contain elements that are not of interest or are harmful, which can be commercially penalized, such as arsenic, antimony, bismuth, mercury, and lead. Therefore, by removing or reducing these elements from the concentrate, the penalties for these elements can be reduced. Typically, the depression of pyrite and other discarded sulfides is achieved by modifying the pH as well as by adding chemical depressants, typically cyanide or sodium metabisulfite

[10] . Several ways of depressing pyrite have been devised. The main methods are as follows: Increase the pH of the solution, for example, by adding lime [1]. Addition of cyanide salts, such as potassium cyanide, sodium cyanide and potassium ferricyanide [2]. Addition of sulfur- and oxygen-based compounds, such as sulfite, bisulfite, metabisulfite, and sulfur dioxide [3], [4], [5], [6], [7] Addition of iron salts, such as ferric sulfate or ferrous sulfate [2] Addition of hypochlorite salts, such as sodium hypochlorite and calcium hypochlorite [8] The use of organic reagents, such as starch, pyrogallic acid and tannic acid [8] Although used industrially in mineral flotation plants, conventional methods for depressing pyrite and other sulfides by adding chemical depressants have several drawbacks. First, they are expensive. Relatively high consumption of consumables, as well as the treatment of process water to clean and prepare it for reuse in the flotation circuits, are also factors. Furthermore, the use of certain depressants such as cyanide is increasingly common. increasingly restricted given its toxicity he risk associated environmental [9]. The process that is the subject of the present invention offers a significant advantage over conventional methods, as it allows for savings in chemical reagents, which currently represent a considerable cost. Specifically, the proposed process and reactor constitute an electrochemical method for the depression of pyrite and other sulfides destined for disposal, which does not necessarily employ chemical depressants. The choice of electrical potential allows the use of any potential value, unlike chemical reagents, which are limited to discrete potential values. Furthermore, it allows for independent variation of pH and electrochemical potential, not only at a macro level but also locally. Consequently, this process allows for greater specificity in the depression action, increasing the resolution in differential flotation between the minerals of interest and unwanted sulfides. Thus, it allows for optimization of the grade-recovery relationship of the metals of interest, offering greater benefits from the plant head. In short, not only is the treatment of the minerals introduced into the plant optimized, but the improvement in concentrate quality can lead to the reclassification of certain minerals, previously considered waste for failing to meet the quality cut, resulting in the processing of minerals that would otherwise be discarded. This would eliminate waste. On the one hand, this could lead to significant savings, as less ore would be moved to produce the same amount of product. On the other hand, it could simplify mine logistics by eliminating the need to avoid or blast and discard certain areas currently considered barren. Furthermore, it could prevent or minimize blending between higher and lower-quality concentrates to achieve specific quality levels. Another advantage is the speed at which the electrical potential changes, which allows for a rapid (virtually instantaneous) response from the flotation process control system, which is relatively slow (typically minutes or hours) in the current system, as it depends on the concentration and flow of chemical reagents, which can remain recirculating in the system for relatively long periods of time. This process also allows for greater Versatility in flotation circuits, since the process water is not chemically conditioned as it is at present, making it easier to vary the flotation conditions in a modular way, within the same circuit, line or treatment plant. BRIEF DESCRIPTION OF THE INVENTION The present invention relates to a process, according to claim 1, and an electrochemical reactor, according to the claim 13, for the depression of iron sulfides and Other disposable elements, primarily pyrite, though not exclusively, in mineral concentration by flotation, which replaces, minimizes, optimizes, or complements the use of depressants and other chemical reagents. This invention is especially relevant for the flotation of sulfide minerals of all types. The process is based on applying an electrical potential using at least one electrode to simulate the electrochemical effect that chemical depressants and other reagents have on mineral particles. Thus, through direct contact between the electrode and the mineral particles, the surface of the mineral to be depressed is altered, increasing its hydrophilic character and preventing its adhesion to the bubbles, resulting in its depression. This electrochemical alteration of the mineral particle surface translates into improved selectivity in flotation separation. However, it does not involve electrostatically attracting or repelling the mineral particles (or mineral-bubble complexes) from the electrode(s). As mentioned, the process consists of applying a potential, using a working electrode, in situ or ex situ, directly or indirectly, to the mineral particles in the pulp. This application requires, or from direct contact between the electrode and the mineral, which is more likely to happen if the particles are in motion, for example, by means of agitation, or from the transfer of potential by means of electrochemical mediators. This is a typically electrolytic process, although it can also be galvanic, in which the working electrode is polarized to specific potential values. These values ​​are chosen to condition the surface of the pyrite or other sulfide species to be removed, in order to increase the hydrophilic character of that surface. Typically, the aim is to catalyze the selective formation of hydroxides on the pyrite surface. For this purpose, the chosen potential is usually positive; the working electrode acts as the anode. Furthermore, this potential is typically set below the electrolysis potential of water to prevent the formation of bubbles on the electrode surface and thus avoid changes in pH.It is worth noting that the application of potential is a variable independent of pH, at least at a macro level (although it would be possible to modify the pH at a macro level, if this entailed changes in pH, this would typically occur at a local level), which allows for greater resolution in the differential flotation of the minerals in question. Altering the pH at a local level can be carried out by using the necessary potential(s) to generate the potential. Consuming protons / hydroxyl ions, e.g., acidification of the medium as a consequence of water hydrolysis, by generating protons. This pH alteration occurs in the local environment of the electrode, without affecting the pH of the overall medium, when the influence of the electrochemical reactions carried out by the electrode is limited, in relation to determining parameters such as relatively high volumes and flows and / or relatively short residence times, which mask the pH changes generated by the electrode(s). If the pH is altered, it most commonly occurs at a local level.However, it would be possible to alter the pH at a macro / general level, since the electrochemical reactions performed by the electrode have a significant influence on the pH of the medium, in relation to determining parameters, such as relatively low volumes and flows and / or relatively long residence times, which allow extending to a macro level the pH changes originally generated locally on the surface of the electrode(s). The process is based on the use of an electrochemical cell within the mineral pulp circuit, at any point in it, either in the same flotation cells or in conditioning tanks or passages or pipes downstream of, or interposed in, the process, pre-existing or added. The electrochemical reactor can take any This system can be configured as a simple reactor with two parallel flat electrodes, or as more complex devices such as column, bed, and / or multitubular reactors, and / or incorporate or utilize at least part of the mineral processing line, such as flotation cells, slurry containers or passages, and mills. It includes any structure or element within the plant or processing line / circuit, with the electrodes (at least partially) submerged in liquid / slurry (at least while in operation). For example, baffles, pipes, passages, conditioning tanks, weighers / cyclones, air or mineral dispersers, agitators, false floors, screens / filters, linings, or mill components such as balls and rods can be lined and / or used as electrodes. The electrodes may be made of any conductive or semiconducting material and may be treated, for example, to modify their affinity with the pulp and / or mineral species and / or liquid(s), for example, by (pre)treatment(s) to increase the hydrophobicity or hydrophilicity of the surface, as well as modified / treated / impregnated / associated with / doped with catalysts or modifiers of potential, activation energy, or other energetic or thermodynamic considerations. Furthermore, the electrodes may be magnets or They can be magnetized, optionally to preferentially attract or repel certain mineral species. Typically, 316L stainless steel electrodes (an alloy of iron, nickel, chromium, molybdenum, and carbon) would be used to prevent electrode oxidation given the medium and potentials employed. These electrodes can take any form, from flat plates (smooth, perforated, or articulated) to the shape of existing structures in the treatment line(s) (or their lining). Furthermore, the surface area can be maximized or modulated by using electrodes with three-dimensional, perforated, or uniquely rough surfaces.The electrodes may be assisted by in-situ or ex-situ systems for cleaning and / or maximizing / modifying current efficiency, for example, mechanical systems to keep the surface clean, prevent / correct / minimize / act on impurities or aggregates, such as brushes or vibration / ultrasound systems for removing adhered particles / species, and / or systems to prevent / correct / mitigate / act on physicochemical problems, such as programs for varying the potential(s) against passivation layers formed on or from the electrode(s) or chemical treatment systems. The reactor may be assisted by... Washing systems such as hoses, pressure washers, and other hydro-cleaning systems, operating manually, semi-automatically, or automatically, may be included, optionally in conjunction with systems for moving these cleaning elements or reactor components, such as hoists, or for emptying / filling the tank housing the reactor. The electrochemical reactor, as well as its housing components, may be equipped with safety systems to prevent, mitigate, or respond to electrical discharges or short circuits, such as separators, rubber seals, insulating linings, grounding, fuses, and intelligent systems to ensure safety. The reactor may also be equipped with suitable mechanical supports for the proper securing of its components. The process has two main modes. In the first, the potential is applied directly to the mineral via the electrode. This requires direct contact between the mineral and the electrode. In the second mode, the potential is applied to the mineral through chemical / electrochemical mediators, typically dissolved in the medium, added to it, or already present (e.g., thiosalts), although they can also be conductive or semiconducting solids, again added to or already present (e.g., mineral particles), or a combination thereof. Furthermore, the process allows combine the two modes, simultaneously, sequentially, in series and / or in parallel, using the same reactor or different reactors. If direct contact between the electrode and the mineral is required, the electrochemical reactor may be assisted by additional mechanisms to promote, maximize, or force such contact. These mechanisms may include, for example, agitators, pumping systems, mixing, aeration, bubbling, and / or vibration to promote or maximize contact, and / or filter presses and / or other types of presses and / or filters to force contact. Physicochemical methods may also be used to modulate the affinity between the electrode and the mineral, such as modulating the hydrophobicity or magnetizing the electrode, optionally to selectively promote (or lack thereof) affinity with certain mineral species. The process that is the subject of the invention achieves several objectives: The primary objective of the process is the depression of iron species, mainly pyrite, to increase the grade of the metal of interest in the concentrate. To achieve this, potentials are applied to the ore, directly and / or indirectly, causing the surface of the species to be depressed to become more hydrophilic. preferably from manner selective, preventing minimizing this effect on the minerals of interest Floating. This effect can be achieved both in the absence and in the presence of reagents and / or pH modifiers, acting independently or in conjunction with these agents. For example, one way to selectively depress pyrite is to catalyze the formation of hydroxides on its surface, which makes it more hydrophilic. Furthermore, potentials can be applied to positively or negatively charge certain mineral species; depending on the charge of the collector(s) and / or reagent(s), this will lead to their flotation or depression. This greater selectivity between the fractions to be floated and depressed results in an increase in the grade of the metal of interest in the floated concentrate. That is, by depressing more iron species, a higher percentage of the metal of interest is obtained in the floated fraction. The second objective of the process is the depression of species containing or associated with elements that are to be removed, primarily penalizing elements such as arsenic, antimony, bismuth, and mercury, as well as elements discarded for economic or logistical reasons (e.g., differential flotation), such as zinc and lead. To this end, as with the depression of iron species, potentials are applied to the ore, directly and / or indirectly, causing the surface of the species to become depleted. that HE wish to depress HE become more hydrophilic, Preferably selectively, preventing or minimizing this effect on the minerals of interest to be floated. Again, this effect can be achieved both in the absence of reagents and / or pH modifiers, as well as in their presence, acting independently or in conjunction with these agents. The third objective of this process is the removal of metals in solution or other substances to be cleaned, through their deposition / precipitation, optionally selective (for example, by choosing the separator and / or potential(s)), preferably within a compartment in the relevant configurations, and preferably by electrodeposition on / constituting the cathode. For example, purging copper in solution by electrodeposition on the cathode minimizes sphalerite activation, while also allowing for the useful recovery of copper. This cleaning is not limited to the removal of these substances from solution, but also includes their transformation into other forms that do not cause or minimize problems arising from them, and / or that reduce their cost (for example, the oxidation of thiosalts). The fourth objective of the process is to promote the recovery of metals or substances of interest, by Promoting floatability, for example, by positively affecting the minerals, optionally by allowing less alkaline pH ranges for the same grade of the metal of interest in the final concentrate, optionally in the presence of reagents such as negative collectors. The fifth objective is the saving / optimization of certain reagents, either by eliminating their addition, minimizing it, or maximizing their effectiveness, such as lime and / or certain collectors, depressants, modifiers, or chemical reagents / additives. This optimization can take place throughout the entire process or in any part of it; for example, by minimizing lime and / or depressants in roughing flotation, while maintaining conventional levels of these reagents downstream of regrinding / in tailings. An added advantage of this is the increased recovery of metals and / or substances of interest, for example, by achieving higher recovery, at least in the roughing concentrate, as a result of processing it at a less alkaline pH. This process does not negatively impact the grade of the metal of interest in the concentrate. This fifth objective consists of improving the resolution in the separation of mineral species, by adding one more dimension (potential) to differential flotation, which is possible because pH and potential are variable independent since in this process we typically We find that the reaction occurs below the hydrolysis potential of water, and by changing the pH, we can ensure that it happens exclusively at a local level, and not globally / macro. This is not possible in conventional flotation, since the potential tends to be linearly dependent on pH. Therefore, to make the potential negative, the pH must necessarily be made alkaline, and vice versa. This tends to negatively impact recovery (if the solution is made alkaline) or the grade of the metal or substance of interest in the final concentrate(s) (if the solution is made acidic). This leaves an opportunity to improve the grade and overall recovery, which is achieved through the use of this process. Finally, the ideal industrial configuration would be the implementation of the process both in a passage (for example, a pipe or enlargement / compartment that houses the reactor in question, optionally using perforated or ring-shaped electrodes or configurations favorable at a hydrodynamic level) or conditioning tank prior to roughing flotation, as well as in a passage like the one above described or preconditioning tank to any tailings and / or flushing stage. The reactor may be configured as a combination and / or matrix of (the) morphological unit(s). The reactor may be installed parallel to the walls of the tank or compartment containing or through which the pulp passes, and / or constituting / utilizing at least part of them, and / or arranged in any way, for example in such a way as to maximize the electrode surface area per volume of pulp, optionally employing reactor mosaics, column reactor configurations and / or bed reactors (e.g. packed, percolator, suspended phase and / or bubbling), (multi)tubular configurations, screening, and / or to promote / modulate the hydrodynamics in the tank(s) or passages, optionally utilizing or acting as a deflector(s).The reactor may take any form, from a simple configuration of two flat electrodes in parallel, to more complex devices such as a reactor that constitutes and / or utilizes at least part of the structures and / or elements of the mineral treatment line(s), such as the flotation cells, tanks, containers or pulp passages, including any element of the plant or treatment line / circuit, such as pipes, conditioning tanks, elements such as air dispersers, agitators, false floors, deflectors, linings and / or structures, and / or elements of the mills such as balls, rods and / or structures. Mechanical / fissile, electrical and / or parameters The system's chemicals can be controlled by intelligent, optionally remote, control systems to monitor and adjust the reactor, optionally in relation to process data such as laboratory analyses, courier data, and physicochemical or mechanical parameters. Furthermore, automated transport systems can be employed for processes such as ore distribution to the electrode, pulp recirculation, liquid / medium and / or solids handling, and / or extraction, cleaning, replacement, movement, modification, or regeneration of electrodes or other reactor components. Additionally, the reactor design could allow for the replacement of the separator(s), electrodes, and / or other constituent elements without the need for disassembly. BRIEF DESCRIPTION OF THE FIGURES To complement the description being made and in order to help a better understanding of the characteristics of the invention, according to a preferred embodiment thereof, a set of figures is included as an integral part of said description, in which, for illustrative and non-limiting purposes, the following has been represented: Figure 1 shows a first example of a reactor formed by a simple electrochemical cell Figure 2 shows a second example of a reactor also formed by a simple electrochemical cell. Figure 3 shows a third example of a reactor that is a variant of the first example. Figure 4 shows a fourth reactor example that is a combination of the second and third reactor examples above. Figure 5 shows a fifth example of a reactor that is a variation of the third example. Figure 6 shows a sixth reactor example that is a combination of the second and fifth examples. Figure 7 shows an example of reactor arrangement within a tank (e.g., conditioning tank). Figure 8 shows an example of reactor arrangement within a passage (e.g., column reactor). Figure 9 shows a block diagram of the iron sulfide depression process. DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for the depression of iron sulfides and other waste elements in the flotation of mineral particles in liquid, which would typically take place after the stages of extraction, crushing, grinding and liquid suspension of the mineral. An example of such processing for copper ores is presented below, illustrated in Figure 9. First, sulfide-rich ore is extracted from Copper is extracted from the mine during blasting. This ore is then transported by dump trucks to the primary crusher, where the diameter of the ore particles is reduced from approximately less than 1000 mm to less than 175 mm. The product from the primary crusher is screened so that particles with a diameter greater than 65 mm pass through the secondary crusher, yielding particles with a diameter less than 65 mm. These particles then pass through the tertiary crusher, resulting in particles with a diameter less than 19 mm. The next step would be a grinding stage, either in a rod mill or a ball mill, to produce particles smaller than 0.2 mm in diameter. Following this, the ore pulp would be agitated in a pre-conditioning tank before the rough flotation stage, which would be an ideal time to apply an electrical potential. This would condition the particles before the first flotation. The product of the rough flotation is the rough concentrate, whose main purpose is to remove most of the gangue (primarily silicates), as well as some of the iron sulfides (particularly pyrite). The product of the roughing flotation would be subjected to a regrinding stage, where the particle diameter would be reduced from less than 0.2 mm to less than 0.05 mm. mm. Next, the ore pulp is agitated in a conditioning tank before the three tailings and the final extraction. This tank could also be used to apply an electrical potential to condition the ore prior to the tailings. Additionally, intermediate conditioning tanks or passages where an electrical potential would be applied could be introduced, for example, between the first and second tailings, as well as between the second and third tailings. The product of the flotation process, after thickening and filtration stages, is the final concentrate, which typically consists of copper sulfides such as chalcopyrite and chalcocite, containing at least 20% copper. The process described above incorporates at least one reactor for applying the electrical potential, and this reactor can have different configurations. Some of the possible reactor configurations are listed below. In all reactor configurations, the mineral may or may not come into contact with the working electrode, although the former is preferred. As mentioned, the contact option involves the particles coming into contact with the working electrode, which can be achieved by agitation or movement of the pulp, thus ensuring contact for at least an instant. In the configuration without contact hint is a mediator employed? An electrochemical medium, present or added, is used to transfer the electrical potential from the electrode to the mineral particles. In this case, direct contact between the mineral and the electrode is not necessary. However, if an electrochemical medium is used, a reactor with direct contact can still be employed, although in that case, ensuring contact from a hydrodynamic standpoint would not be required. Other options include using an ex-situ reactor or covering the electrode of interest with a separator to prevent direct contact with the mineral. Typically, a relatively low potential difference, from 0 to 12 volts, is used between the anode and cathode. The first reactor configuration is a simple electrochemical cell. This cell, illustrated in Figure 1, consists of a counter electrode (1), a working electrode (2), a power supply (3), and at least one connection between these three elements (4). In this example, the anodic and / or cathodic and / or medium and / or cell potentials can be controlled with a potentiometer and / or potentiostat, and / or with any power supply / circuit / electrical component (battery, plug, rectifier, etc.) that can be assisted by a potentiometer and / or potentiostat. The second reactor configuration is a cell The electrodes are partially or totally isolated from the pulp medium and / or other electrode(s) and / or liquid by a separator. This arrangement, which prevents contact between the counter electrode and the mineral particles through a physical separator, is the most favorable process configuration. This cell, illustrated in Figure 2, consists of a counter electrode (1), a working electrode (2), a power supply (3), and a connection (4) between these three elements. The anodic and / or cathodic and / or medium and / or cell potentials can be controlled with a potentiometer and / or potentiostat, and / or with any power supply / circuit / electrical component (battery, plug, rectifier, etc., which may be assisted by a potentiometer and / or potentiostat).Furthermore, it consists of the separator(s) (5), which may be made up of ion exchange membrane(s), for example, anion or cationic exchange membranes, both generic and for specific ions / elements / compounds, fluid membrane(s), organic phase(s), dialysis membrane(s), grid(s), perforated plate(s) or structure(s), ion bridge(s), filter(s), sponge(s), (porous) battery separator(s) or of any other type, or a combination thereof. These separators may be located at a certain distance from the electrode(s), e.g., configuration. "finitegap" (finite gap), or in direct contact with the electrode(s), e.g. "zerogap" (zero gap) configuration, or as a combination thereof. The third reactor configuration is a variant of the first configuration. This cell, illustrated in Figure 3, consists of the same elements as the first configuration (a counter electrode (1), a working electrode (2), a power supply (3), and a connection(s) between these three elements (4), where the anodic and / or cathodic and / or medium and / or cell potentials can be controlled with a potentiometer and / or potentiostat, and / or with any power supply / circuit / electrical component (battery, plug, rectifier, etc.) that may be assisted by a potentiometer and / or potentiostat). In addition, it consists of a third electrode (5), optionally a reference electrode such as silver / silver chloride, connected to at least one of the electrodes by a connection(s) (7), and a device (6) for measuring the potential difference between the working electrode and the third electrode and / or between the counter electrode and the third electrode.Said element (6) is preferably a voltmeter or multimeter, and may have / be connected to / collaborate with feedback / response / monitoring / adjustment systems related to the control system of the anodic potential(s) and / or . cathodic and / or medium and / or cell and / or partial ionic and / or pulp and / or zeta or a combination thereof. The fourth reactor configuration is a combination of the second and third configurations. This cell, illustrated in Figure 4, consists of the same elements as the third configuration (a counter electrode (1), a working electrode (2), an electrical supply (3), and a connection(s) between these three elements (4), where the anodic and / or cathodic and / or medium and / or cell potentials can be controlled with a potentiometer and / or potentiostat, and / or with any electrical supply / circuit / electrical component (battery, plug, rectifier, etc., which may be assisted by a potentiometer and / or potentiostat), and a third electrode (5), optionally a reference electrode such as silver / silver chloride, connected to at least one of the electrodes by means of a connection(s) (7), and an element (6) for measuring the potential difference between the working electrode and the third electrode and / or between the counter electrode and the third electrode.Said element (6) is preferably a voltmeter or multimeter, and may have / be connected to / collaborate with feedback / response / monitoring / adjustment systems related to the control system of the anodic and / or cathodic and / or medium and / or cell and / or partial ionic potentials and / or . of the pulp and / or zeta or a combination thereof. Furthermore, like the second configuration, it consists of the separator(s) (8), which again may be made up of ion exchange membrane(s), for example, anion or cation exchange membranes, both generic and for specific ions / elements / compounds, dialysis membrane(s), fluid membrane(s), organic phase(s), grid(s), perforated plate(s) or structure(s), ion bridge(s), sponge filter(s), (porous) battery separator(s) or of any other type, or a combination thereof. These separators may be located at a certain distance from the electrode(s), e.g., "finitegap" configuration, in direct contact with the electrode(s), e.g., "zerogap" configuration, or as a combination thereof. The fifth reactor configuration is a variation of the third configuration. This cell, illustrated in the Figure 5 consists of the same elements as the third configuration. However, the arrangement of these elements is different. As in the third In this configuration, the reactor consists of a counter electrode (1), a working electrode (2), an electrical input (3) and a connection / s between these three elements (4), where the anodic and / or cathodic and / or medium and / or cell potentials and / or partial ionic and / or pulp and / or zeta or a combination of the same, and / or with any electrical input / circuit / electrical component (battery, plug, rectifier, etc. which may be assisted by a potentiometer and / or potentiostat). In this case, the third electrode, typically the reference electrode (5), is connected to the electrical input (3) directly or remotely, optionally by means of a connection or connections (7). The electrical input may consist of or be connected / coupled to a potentiostat / potentiometer / rheostat or any monitoring / control / adjustment system, optionally to modify the cell potential based on and / or to control / adjust the anodic and / or cathodic and / or medium and / or cell and / or partial ionic and / or pulp and / or zeta potentials or a combination thereof. The sixth reactor configuration is a combination of the second and fifth configurations. This cell, illustrated in Figure 6, consists of the same elements as the fifth configuration (a counter electrode) (1), a working electrode (2), an electrical input (3), a connection(s) between these three elements (4), where the anodic and / or cathodic and / or medium and / or cell potentials can be controlled with a potentiometer and / or potentiostat, and / or with any electrical input / circuit / electrical component (battery, plug, rectifier, etc. which may be assisted by a potentiometer and / or potentiostat), and a reference such as silver / silver chloride, connected to the electrical supply (3) directly or remotely, optionally by means of a connection / s (7). The electrical supply may consist of or be connected / coupled to a potentiostat / potentiometer / rheostat or any monitoring / control / adjustment system, optionally to modify the cell potential as a function of and / or to control / adjust the anodic and / or cathodic and / or medium and / or cell and / or partial ionic and / or pulp and / or zeta potentials or a combination thereof).Furthermore, like the second configuration, it consists of the separator(s) (8), which again may be made up of ion-exchange membrane(s), for example, anion or cationic exchange membranes, either generic or for specific ions / elements / compounds, dialysis membrane(s), fluid membrane(s), organic phase(s), grid(s), perforated plate(s) or structure(s), ion bridge(s), sponge filter(s), (porous) battery separator(s) or of any other type, or a combination thereof. These separators may be located at a certain distance from the electrode(s), e.g., a "finitegap" configuration, in direct contact with the electrode(s), e.g., a "zerogap" configuration, or as a combination thereof. The reactor of any of the configurations uses at least one anode and at least one cathode, and is electro-assisted by applying and / or controlling an electrical power source, to control and / or measure and / or modulate one or more of (i) cell potential(s), (ii) partial and / or relative and / or half-cell anodic potential(s), (iii) partial and / or relative and / or half-cell cathodic potential(s), (iv) medium potential(s), (v) partial potential(s) of species in solution, (vii) pulp potential(s), and (viii) zeta or surface potential(s) of the mineral particles. A simple example of its use, as illustrated in Figure 7, involves introducing several electrochemical reactors into a tank (1) with an agitator (5). The reactors (2, 3, 4, and 6) could be arranged along the tank wall so that the potential is applied to the mineral particles (directly or indirectly) during a conditioning stage, for example, prior to or interleaved with roughing flotation or other flotations, such as selective, tailings, stripping, or depletion flotation. Any possible cell shape and configuration could be used, as well as any arrangement of the different reactors, not necessarily parallel to the tank walls. For example, the process could be used in the Pre-conditioning tank prior to roughing flotation. This tank would typically receive between 800 and 1,200 tons of ore per hour, at 20-40% w / v water content. If it is copper ore, the incoming ore would typically contain between 0.4 and 2% copper, between 2 and 30% sulfur, between 1 and 20% iron, between 0.1 and 5% zinc, as well as gangue (typically silicates) and other elements in smaller quantities. The ore entering the tank typically has a D80 of between 100 and 250 pm. In this tank, it is agitated for approximately 2 to 5 minutes before being sent to roughing flotation. After applying potential during this conditioning stage, for example, between 1 and 12 V between the anode and cathode, the copper grade of the concentrate could be increased by several points (e.g., from 20% to 24% copper without and with the reactor, respectively), as well as the copper recovery by several points (e.g., from 86% to 88% without and with the reactor, respectively). A lower pH could also be used for roughing flotation, maintaining the same grade (e.g., 20%) but increasing the recovery (e.g., an increase of between 4% and 6%). Normally, this would not be possible without using the reactor, since lowering the pH would also lower the recovery. The copper content in the concentrate. On the one hand, the utilization A lower pH in roughing (e.g., pH 10 instead of pH 11.5) would allow for significant lime savings (typically several tons of lime per day), while also yielding greater profit from the same feedstock or ore that is fed into the plant and processed (typically containing 1% copper, which is concentrated to 20%), since less copper would be discarded. Furthermore, if this process were used to increase the copper grade in the concentrate, the use of depressants such as sodium metabisulfite (e.g., 400 g / ton of regrind) could be reduced or even completely eliminated. Another example of use, illustrated in Figure 8, involves introducing pulp into a passage, for example, a column reactor (1), containing one or more electrochemical cells (2) that can take any shape. The pulp would be introduced at least through one inlet (3) and exit at least through one outlet (4). The electrodes could be of any shape, employing, for example, large specific surface areas. References: [1] IN Plaksin and GA Miasnrkova; "Some Data on Depression of Pyrite by Lime"; Academy of Science SSSR, No. 4 (1956) [2] K. Milena; "Depression of pyrite mineral with cyanide and ferrous / ferric salts"; Underground Mining Engineering 19 (2011) 149-155 [3] SR Grano, NW Johnson, J. Ralston; "Control of the solution interaction of metabisulphite and ethyl xanthate in the flotation of the Hilton ore of Mount Isa Mines Limited, Australia"; Minerals Engineering, 10, No.l, 17-45 (1997a). [4] S.R. Grano, C.A. Prestidge, J. Ralston; "Solution interaction of ethyl xanthate and sulphite and its effect on galena flotation and xanthate adsorption"; International Journal of Mineral Processing, 52, 161-186 (1997b) . [5] T.N. Khmeleva, D.A. Beattie, T.V. Georgiev, W.M. Skinner; "Surface study of the effect of sulphite ions on copper-activated pyrite pre-treated with xanthate"; Minerals Engineering, 16, 601-608 (2003) [6] T.N. Khmeleva, W.M. Skinner, D.A. Beattie; "Depression mechanisms of sodium bisulphite in the xanthatecollectorless flotation of copper activated sphalerite"; International Journal of Mineral Processing, 76, 43-53 (2005) [7] T.N. Khmeleva, J.K. Chapelet, W.M. Skinner, D.A. Beattie; "Depression mechanisms of sodium bisulphite in the xanthate-induced flotation of copper activated sphalerite"; International Journal of Mineral Processing, 79, 61-75 (2006) [8] A. Guanghua, Y. Zhou, Y. Wang; "A Study on the Combined Depressant for the Cu-S Separation in Low Alkaline Medium and its Depressing Mechanism"; Procedía Engineering, Volume 102, Pages 338-345 (2015) [9] B. Ball, R.S. Rickhard, edited by M.C. Fuerstenau; "A. M. Gaudin Memorial Volume"; American Institute of Mining Metallurgical and Petroleum Engineers, New York, 458 (1976).

[10] M. C. Fuerstenau, G. J. Jameson, R. Yoon; "Froth Flotation: A Century of Innovation"; SME (2007)

[11] S. Ramachandra Rao; "Surface Chemistry of Froth Flotation: Volume 1: Fundamentals"; Springer Science & Business Media, Jun 29 (2013) .

Claims

CLAIMS 1. A process for the depression of iron sulfides and other waste elements in the flotation of mineral particles in liquid, which, after the stages of extraction, crushing, grinding and liquid suspension of the mineral, is characterized in that at least one sulfide is electrochemically depressed by the application of at least one electrical potential.

2. Process, in accordance with claim 1, characterized in that at least one iron sulfide or other disposable element is electrochemically depressed by the direct action of at least one electrode, there being at least part direct contact between the electrode and the mineral particles.

3. Process, in accordance with claim 1, characterized in that at least one iron sulfide or other disposable element is electrochemically depressed by the indirect action of at least one electrode, wherein the at least one electrode potential is transferred to the mineral particles by means of at least one mediator, typically dissolved in the liquid.

4. Process, in accordance with claim 1, characterized in that at least one potential is less than the electrical potential required to oxidize and / or reduce water.

5. Process, in accordance with the claim 1, characterized in that at least one potential of at least one electrode is modulated without altering the pH of the liquid.

6. Process, in accordance with claim 5, characterized by the fact that the pH is altered only at a local level, but not at a macro / general level.

7. Process, in accordance with claim 1, characterized by an alteration of the pH at a macro / general level.

8. Process, in accordance with the preceding claims, characterized in that the cathode electrodeposits and / or precipitates and / or removes metals or other compounds from the solution, optionally selectively, by compartments and / or sequentially.

9. A process, in accordance with the preceding claims, characterized in that other mineral species are floated or depressed differentially, optionally by the use of chemical reagents and / or by electrodes, simultaneously, in parallel, in series, sequentially and / or in different treatment lines, for example, to obtain different copper and zinc concentrates.

10. Process, in accordance with claim 1, characterized in that the mineral is subjected to a pretreatment additional treatment For example, biotreatments, passivation or oxidation by aeration.

11. Process, in accordance with the preceding claims, characterized in that the liquid is fresh water, mains water, recirculated process water, cleaned / treated process water and / or distilled or otherwise treated water, which optionally contains or has added active agents at the electrochemical and / or pH level.

12. Process, in accordance with claim 1, characterized in that it is (a) galvanic, or (b) electrolytic.

13. Electrochemical reactor for the treatment of mineral pulp, in order to depress iron sulfides and other waste elements in the flotation of mineral particles in liquid, characterized in that it comprises: At least one counter electrode (1), At least one working electrode (2), At least one electrical source (3) and At least one connection between these three elements (4).

14. Reactor, in accordance with claim 13, characterized in that one of the electrodes is at least partially covered or within a delimited compartment to isolate said electrode from the mineral pulp.

15. Reactor, in accordance with claim 14, characterized in that said electrode is delimited by an ion exchange membrane(s), for example anion or cation exchange membranes, a dialysis membrane(s), liquid membrane(s), organic phase(s), a grid(s), ion bridge(s), filter(s), sponge(s), separator(s) (porous) for batteries or of any kind, or a combination of the above, arranged in any way, including "zerogap" and "finitegap" configurations.