Method for collaborative resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore

Abstract

This application provides a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore, belonging to the field of hydrometallurgy. The method involves mixing high-arsenic gold concentrate and silver-manganese ore in a specific ratio, adding an oxidizing liquid to adjust the slurry concentration, and then mechanically intensifying the grinding process in an acid-resistant ball mill. During the grinding process, in the presence of the oxidizing liquid, pyrolusite in the silver-manganese ore and arsenopyrite in the high-arsenic gold concentrate undergo a redox reaction. Arsenic and iron enter the liquid phase in ionic form, while sulfur remains in the slag as elemental sulfur. After grinding, solid-liquid separation is performed to obtain arsenic-removed slag and arsenic-removed liquid. The arsenic-removed slag undergoes biological oxidation pretreatment, followed by solid-liquid separation to obtain oxidation slag and oxidation liquid. The oxidation slag is fed into a cyanidation system to recover gold and silver. The arsenic-removed liquid is treated to remove impurities, and manganese is recovered to obtain manganese salt products. The oxidation liquid and the tailings after manganese recovery are recycled. This application achieves the synergistic utilization of high-arsenic gold concentrate and low-grade pyrolusite ore through a mechanically intensified reaction.

Description

Technical Field

[0001] This invention relates to the field of hydrometallurgical technology, specifically to a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore. Background Technology

[0002] Gold in arsenic-bearing gold ores exists in a fine-grained state and encapsulated within pyrite or arsenopyrite. Direct cyanide leaching typically yields a gold recovery rate below 20%. Currently, the main processing techniques for these difficult-to-process gold ores include oxidative roasting, biological oxidation, and hot-press oxidation. However, traditional roasting processes inevitably produce harmful fumes such as sulfur dioxide and arsenic oxide, requiring complex and costly flue gas treatment and dust collection systems. Furthermore, the high temperatures required for roasting can cause low-melting-point oxides in the material to secondary encapsulate the gold, leading to a decrease in gold recovery. Hot-press oxidation requires high temperature and pressure conditions, demanding technical requirements, stringent equipment material specifications, and high infrastructure and operating costs.

[0003] Biological oxidation has significant advantages such as mild reaction conditions, environmental friendliness, and relatively low investment, making it one of the most promising methods for pretreatment of arsenic-containing refractory gold ores. However, when using biological oxidation to treat arsenic-containing gold concentrates, the arsenic content is generally required to be no more than 8%. If the arsenic content exceeds this range, a two-stage biological oxidation process is required, leading to prolonged oxidation time and increased pretreatment costs. When the arsenic content exceeds 15%, the difficulty of biological oxidation increases significantly. This is mainly because the arsenic ions released during the dissolution process of arsenic-containing minerals inhibit microbial activity, reduce pretreatment efficiency, and consequently affect the overall pretreatment effect of the gold concentrate, even causing the process to malfunction.

[0004] In view of this, it is necessary to design a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore to solve the above problems. Summary of the Invention

[0005] In view of the technical problems existing in the background art, this application provides a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore, which aims to solve the technical problems of low bio-oxidation efficiency or even failure to operate normally due to excessive arsenic content in high-arsenic gold concentrate, and the difficulty in synergistic recovery of manganese and silver resources in low-grade silver-manganese ore, as well as the high energy consumption or long process of existing processes.

[0006] This application provides a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore, comprising the following steps: S1. High-arsenic gold concentrate and silver-manganese ore are mixed in a certain proportion, and an oxidizing liquid is added to adjust the slurry concentration to 40-70%. Mechanical fine grinding is carried out in an acid-resistant ball mill until the particle size of -0.045mm accounts for 80-95%. During the fine grinding process, in the presence of the oxidizing liquid, pyrolusite in the silver-manganese ore and arsenopyrite in the high-arsenic gold concentrate undergo a redox reaction. Arsenic and iron enter the liquid phase in ionic form, while sulfur remains in the slag in elemental form. After the fine grinding is completed, solid-liquid separation is performed to obtain arsenic-removed slag and arsenic-removed liquid. S2. The arsenic removal slag is subjected to biological oxidation pretreatment, followed by solid-liquid separation to obtain oxidation slag and oxidation liquid; the oxidation liquid is returned to step S1 for slurry preparation; the oxidation slag is fed into the cyanidation system to recover gold and silver; S3. After the arsenic removal liquid is treated to remove impurities, the manganese in it is recovered to obtain manganese salt product; the tail liquid after manganese recovery is returned to step S2 for biological oxidation slurry preparation.

[0007] As a further improvement of this application, in step S1, the mass ratio of the high-arsenic gold concentrate to the silver-manganese ore is (2~5):1.

[0008] As a further improvement to this application, the manganese in the silver-manganese ore exists in the form of pyrolusite, and the manganese grade is 8-30%.

[0009] As a further improvement of this application, in step S1, the pH value of the slurry after mechanically enhanced fine grinding is less than 2.

[0010] As a further improvement of this application, in step S2, the slurry concentration of the bio-oxidation pretreatment is 10-18%, and the oxidation time is 4-6 days.

[0011] As a further improvement of this application, the bacterial strains used in the biological oxidation pretreatment are one or more of the following: thiobacillus ferrooxidans, thiobacillus thiooxidans, thiobacillus ferrooxidans, and Leptospira ferrooxidans.

[0012] As a further improvement of this application, in step S3, the method for recovering manganese from the arsenic removal solution is as follows: first remove impurities, and then use an extraction-back-extraction-evaporation crystallization process to prepare manganese sulfate product; or first remove impurities, and then use a precipitation-washing-drying process to prepare manganese carbonate product.

[0013] As a further improvement of this application, in step S1, the fineness of the high-arsenic gold concentrate is 80-95% of the material with a fineness of -0.074mm; and the fineness of the silver-manganese ore is 70-85% of the material with a fineness of -0.074mm.

[0014] The beneficial effects of this application are as follows: This application provides a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore. The method involves mixing high-arsenic gold concentrate and silver-manganese ore in a specific ratio, adding an oxidizing liquid to adjust the slurry concentration to 40-70%, and then mechanically grinding the mixture in an acid-resistant ball mill until 80-95% of the particles are -0.045 mm. During the grinding process, in the presence of the oxidizing liquid, the pyrolusite in the silver-manganese ore and the arsenopyrite in the high-arsenic gold concentrate undergo a redox reaction. Arsenic and iron enter the liquid phase as ions, while sulfur remains in the slag as elemental sulfur. After grinding, solid-liquid separation is performed to obtain arsenic-removed slag and arsenic-removed liquid. The arsenic-removed slag undergoes biological oxidation pretreatment, followed by solid-liquid separation to obtain oxidation slag and oxidation liquid. The oxidation liquid is returned to step S1 for slurry preparation. The oxidation slag enters a cyanidation system to recover gold and silver. The arsenic-removed liquid is treated to remove impurities, and manganese is recovered to obtain manganese salt products. The tailings after manganese recovery are returned to step S2 for biological oxidation slurry preparation. This application fully integrates the chemical properties of the materials and, based on the main process of bio-oxidation pretreatment, achieves the synergistic utilization of resources such as high-arsenic gold concentrate and low-grade pyrolusite. This process has advantages such as a simple flow, environmental friendliness, and high metal recovery rate, demonstrating promising industrial application prospects in the processing of high-arsenic gold concentrate and low-grade pyrolusite.

[0015] This application innovatively develops a process for the synergistic removal of arsenic and manganese from high-arsenic gold concentrate and pyrolusite through a mechanically enhanced reaction in a process-generated oxidation environment. This solves the problem of microbial inhibition during the bio-oxidation of high-arsenic gold concentrate and exposes silver in pyrolusite. Based on the principle of mechanically enhanced reaction, this application can ensure rapid reaction between pyrolusite and arsenopyrite during grinding, while eliminating further reaction obstacles caused by the formation of elemental sulfur, thereby improving the removal rate of arsenic and iron during the mechanically enhanced reaction process.

[0016] In the entire process, the mechanical enhancement reaction stage effectively reduces the burden on subsequent bio-oxidation, significantly improves bio-oxidation efficiency, shortens processing time by 15%-25%, and reduces the operating cost of the bio-oxidation stage. Simultaneously, the acidic bio-oxidation liquid produced during the bio-oxidation process can be recycled for mechanical enhancement operations, serving both as a reaction medium and providing acid for the leaching reaction of pyrolusite, reducing the amount of purchased acid required and saving reagent costs. This application expands the applicable range of raw materials based on existing bio-oxidation processes, alleviates the tight supply of raw materials for bio-oxidation processes, and can effectively revitalize stagnant mineral resources such as low-grade pyrolusite.

[0017] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of this application, the accompanying drawings used in this application will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without any creative effort.

[0019] Figure 1 A flowchart of a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore provided in this application embodiment; Figure 2 This is a scanning electron microscope image of the manganese sulfate product obtained in Example 1 of this application; Figure 3 This is a photograph of the manganese sulfate product obtained in Example 1 of this application. Detailed Implementation

[0020] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0022] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0023] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0024] In the gold industry, gold in arsenic-containing, refractory gold ores is often encased in fine-grained form within pyrite or arsenopyrite crystals. Direct cyanide leaching yields extremely low gold recovery rates, necessitating pretreatment to decompose the gold-bearing sulfides. Currently, among the main pretreatment methods, oxidative roasting produces harmful fumes and easily causes secondary gold encapsulation; hot-press oxidation requires demanding equipment and involves huge investments; and while bio-oxidation offers advantages such as environmental friendliness and mild operating conditions, it is limited by the toxic inhibitory effect of arsenic ions on microbial activity, generally requiring the arsenic content of the raw material to be below 8%. When the arsenic content exceeds 15%, the processing efficiency drops significantly or even becomes unusable. Therefore, how to achieve the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore, efficiently recover gold, silver, and manganese under mild conditions, and solve the problem of high arsenic content inhibiting bio-oxidation, is a pressing technical challenge in this field.

[0025] To address the problem of arsenic inhibition of bio-oxidation in high-arsenic gold concentrate and the technical challenge of mild and synergistic recovery of manganese and silver resources in low-grade silver-manganese ore, this application provides a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore. This method involves mixing the high-arsenic gold concentrate and silver-manganese ore and then mechanically intensifying and finely grinding them. Arsenic is pre-removed using a process-generated oxidizing liquid. The arsenic-removed slag then enters the bio-oxidation section, forming a two-stage series process of mechanically intensified arsenic removal and bio-oxidation. An internal circulation system for the oxidizing liquid and tailings is also constructed. This approach reduces the arsenic load in the bio-oxidation section from the source, solves the problem of high arsenic content inhibiting microbial activity, and simultaneously achieves the comprehensive recovery of gold, silver, and manganese.

[0026] Please refer to Figure 1 This application provides a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore, comprising the following steps: S1. High-arsenic gold concentrate and silver-manganese ore are mixed in a certain proportion, and oxidizing liquid is added to adjust the slurry concentration to 40-70%. Mechanical fine grinding is carried out in an acid-resistant ball mill until the particle size of -0.045mm accounts for 80-95%. During the fine grinding process, in the presence of oxidizing liquid, pyrolusite in silver-manganese ore and arsenopyrite in high-arsenic gold concentrate undergo redox reactions. Arsenic and iron enter the liquid phase in ionic form, while sulfur remains in the slag in elemental form. After fine grinding, solid-liquid separation is carried out to obtain arsenic-removed slag and arsenic-removed liquid. S2. The arsenic removal slag is pretreated by biological oxidation, followed by solid-liquid separation to obtain oxidation slag and oxidation liquid; the oxidation liquid is returned to step S1 for slurry preparation; the oxidation slag enters the cyanidation system to recover gold and silver. S3. After the arsenic removal liquid is treated to remove impurities, the manganese in it is recovered to obtain manganese salt products; the tail liquid after manganese recovery is returned to step S2 for biological oxidation slurry preparation.

[0027] In the technical solution of this application embodiment, high-arsenic gold concentrate and silver-manganese ore are mixed and then mechanically intensified and finely ground in an oxidizing liquid environment. Utilizing the strong oxidizing property of pyrolusite in the silver-manganese ore, arsenopyrite is oxidized and decomposed under acidic conditions. Arsenic and iron enter the liquid phase in ionic form, while sulfur remains in the slag as elemental sulfur. Simultaneously, MnO2 is reduced to Mn. 2+ Entering the liquid phase; As produced by the reaction 3+ Fe 2+ Under the continued action of pyrolusite, it is further oxidized to As. 5+ and Fe 3+ This facilitates the subsequent neutralization and formation of a stable ferric arsenate precipitate. Through mechanically enhanced fine grinding, elemental sulfur generated at the reaction interface is continuously stripped away, eliminating its hindrance to the reaction and achieving efficient arsenic removal. The arsenic content in the arsenic-removed slag is significantly reduced, and it no longer significantly inhibits microbial activity after entering the biological oxidation stage, thus improving the efficiency of biological oxidation. Meanwhile, the manganese in the arsenic-removed liquid, after impurity removal, can be used to prepare industrial-grade manganese sulfate or manganese carbonate products.

[0028] Furthermore, in some embodiments, in step S1, the mass ratio of high-arsenic gold concentrate to silver manganese ore is (2~5):1.

[0029] In the technical solution of this application embodiment, the amount of silver manganese ore added must be sufficient to oxidize the arsenopyrite in the high-arsenic gold concentrate to achieve complete removal of arsenic. If the proportion of silver manganese ore is too low, the oxidant will be insufficient, the arsenic removal will be incomplete, and the residual arsenic content in the arsenic removal slag will still be high. This will still inhibit the activity of microorganisms during subsequent biological oxidation, affecting the overall treatment efficiency. If the amount of silver manganese ore is excessive, it will introduce a large amount of gangue and impurities, increasing the difficulty of subsequent impurity removal processes and reagent consumption. In addition, if too much silver manganese ore enters the system, the manganese reduction will be incomplete, and some silver will not be dissociated, affecting the silver recovery rate of cyanide extraction.

[0030] Furthermore, in some embodiments, manganese in the silver manganese ore exists in the form of pyrolusite, with a manganese grade of 8-30%.

[0031] In the technical solution of this application embodiment, pyrolusite acts as an oxidant in the oxidative decomposition reaction of arsenopyrite in high-arsenic gold concentrate, and is itself reduced to Mn. 2+ The manganese is leached into the arsenic removal solution. Simultaneously, the moderate manganese grade provides sufficient MnO2 for the oxidation of arsenopyrite while avoiding the rapid accumulation of gangue and impurities associated with excessively high-grade manganese ore. This ensures the feasibility of subsequent impurity removal and manganese recovery processes in the arsenic removal solution. During the dissolution process of the pyrolusite through redox reactions, the silver encapsulation is broken, allowing silver to accumulate in the arsenic removal slag. After bio-oxidation, it enters the oxidation slag and is ultimately recovered in the cyanidation system.

[0032] Furthermore, in some embodiments, in step S1, the pH value of the slurry is less than 2 after mechanically enhanced fine grinding.

[0033] In the technical solution of this application embodiment, after the high-arsenic gold concentrate and silver-manganese ore are mixed and slurried, arsenopyrite begins to oxidize and decompose in the natural acidic environment of the oxidation liquid. Arsenic and iron in the minerals will enter the liquid phase as trivalent arsenic ions and divalent ferric ions, respectively, and generate pentavalent arsenic ions and trivalent ferric ions under the action of pyrolusite. The oxidation liquid is the liquid obtained by solid-liquid separation after biological oxidation in step S2. In the initial stage of the process, when there is no return oxidation liquid, an acidic solution with pH < 2 prepared by water and sulfuric acid can be used as a substitute oxidation liquid for slurry preparation. After the process flow is connected and the oxidation liquid is produced in step S2, it is switched to circulating oxidation liquid.

[0034] Furthermore, in some embodiments, in step S2, the slurry concentration of the bio-oxidation pretreatment is 10-18%, the oxidation time is 4-6 days, and the bacterial strain used is one or more of the following: thiobacillus ferrooxidans, thiobacillus thiooxidans, thiobacillus ferrooxidans, and Leptospira ferrooxidans.

[0035] In the technical solution of this application embodiment, since the mechanically enhanced fine grinding in step S1 has removed most of the arsenic in the high-arsenic gold concentrate, the arsenic content in the arsenic removal slag entering the bio-oxidation section is greatly reduced, and it no longer significantly inhibits the activity of microorganisms. Therefore, bio-oxidation can be carried out smoothly under conventional slurry concentration and conventional bacterial conditions, without the need for two-stage bio-oxidation or the addition of additional oxidants, catalysts, or other enhancement methods. Water or recycled tailings can be added to adjust the slurry concentration. At the same time, since the arsenic load has been greatly reduced at the front end, the efficiency of bio-oxidation is significantly improved, and the oxidation time can be shortened by 15% to 25%. While ensuring the full oxidation and decomposition of sulfide minerals and the full exposure of gold, the pretreatment time and operating costs are significantly reduced.

[0036] Furthermore, in some embodiments, in step S3, the method for recovering manganese from the arsenic removal solution is as follows: first, remove impurities, and then use an extraction-back-extraction-evaporation crystallization process to prepare manganese sulfate product; or first, remove impurities, and then use a precipitation-washing-drying process to prepare manganese carbonate product.

[0037] In the technical solution of this application embodiment, the arsenic removal solution contains Mn leached through a mechanically enhanced reaction. 2+ It also contains Fe 3+ As 5+ Because manganese contains impurities such as iron and arsenic, it is necessary to remove these impurities before recovering manganese to obtain a pure manganese-containing solution. Then, manganese is selectively extracted using an extractant such as C272. After back-extraction to obtain a manganese-rich solution, it is evaporated and crystallized to obtain industrial-grade manganese sulfate. Alternatively, ammonium bicarbonate or other precipitants can be added to the manganese-rich solution after impurity removal to allow the manganese to precipitate. 2+The manganese carbonate precipitates out as manganese carbonate, and after washing and drying, industrial-grade manganese carbonate is obtained. The tail liquid after manganese recovery is returned to step S2 for biological oxidation slurry preparation, achieving the recycling of process water and reducing wastewater discharge. Specifically, impurity removal can be achieved by adding a neutralizing agent to adjust the pH to 3.5-5, reducing the Fe content in the liquid phase. 3+ Hydrolysis produces ferric hydroxide precipitate, while As 5+ with Fe 3+ Ferric arsenate is formed and co-precipitated to remove it. After solid-liquid separation, a purified manganese-containing liquid is obtained. Depending on the product purity requirements, calcium and magnesium removal agents and / or heavy metal removal agents can be added to the purified manganese-containing liquid for further purification to remove impurities such as calcium, magnesium, copper, zinc, cobalt, nickel, and lead.

[0038] Furthermore, in some embodiments, in step S1, the fineness of the high-arsenic gold concentrate is 80-95% for materials with a fineness of -0.074mm; and the fineness of the silver-manganese ore is 70-85% for materials with a fineness of -0.074mm.

[0039] In the technical solution of this application embodiment, the high-arsenic gold concentrate and silver-manganese ore have a certain initial fineness before mechanically enhanced fine grinding, ensuring that they have a certain degree of monomer dissociation before mixed fine grinding, so that the two can fully contact and undergo redox reactions during the subsequent mechanically enhanced fine grinding process. After mechanically enhanced fine grinding, the two materials together achieve a finer particle size of -0.045mm, accounting for 80% to 95%, which is beneficial to the subsequent solid-liquid separation and bio-oxidation processes.

[0040] The following are some specific embodiments. It should be noted that the embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they shall be performed in accordance with the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be obtained commercially.

[0041] Example 1 This embodiment provides a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore. The high-arsenic gold concentrate contains 86% material with a fineness of -0.074 mm, and the silver-manganese ore contains 75% material with a fineness of -0.074 mm. The contents of the main elements are shown in Tables 1 and 2. Table 1. Multi-element analysis results of high-arsenic gold concentrate Table 2. Multi-element analysis results of low-grade silver-manganese ore. Specifically, the following steps are included: S1. High-arsenic gold concentrate and silver-manganese ore are mixed at a mass ratio of 2:1 and added to a mixing tank containing oxidizing liquid (initially a sulfuric acid solution with pH < 2). The slurry concentration is 40%. After uniform mixing, the mixture is pumped into a ball mill for mechanically enhanced fine grinding until 80% of the particles are -0.045mm. At the end, the slurry pH is 1.6. Then, the finely ground slurry is subjected to solid-liquid separation to obtain arsenic-removed slag and arsenic-removed liquid. S2. The arsenic removal residue is adjusted to a slurry concentration of 15% using the tailings from manganese extraction or water, and then transferred to a bio-oxidation reactor for pretreatment. The bacterial strain used is commercially available *Thiobacillus ferrooxidans* (ATCC 23270), which has not undergone special acclimation. The bio-oxidation temperature is 40℃, dissolved oxygen is 4 mg / L, and the oxidation time is 6 days. After the bio-oxidation is completed, solid-liquid separation is performed to obtain oxidation residue and oxidation liquid. The oxidation liquid is returned to step S1 for slurry preparation. The oxidation residue enters the cyanidation system to recover gold and silver. S3. After removing Fe and As impurities from the arsenic-removing solution, manganese is extracted and recovered using C272 extractant. The manganese-rich solution is then back-extracted and crystallized by evaporation to prepare manganese sulfate. The obtained manganese sulfate product meets industrial-grade standards. The tail liquid after manganese recovery is returned to step S2 for biological oxidation slurry preparation.

[0042] The scanning electron microscope image of the manganese sulfate product obtained in Example 1 is shown below. Figure 2 As shown in the image, the product exhibits a regular blocky morphology, with uniform particle distribution and no impurities adhering to it, indicating a good crystallization process and high product purity; the actual product image is shown below. Figure 3 As shown in the figure; multi-element analysis is shown in Table 3.

[0043] Table 3. Multi-element analysis results of the manganese sulfate product prepared in Example 1 Example 2 This embodiment provides a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore, including the following steps: S1. High-arsenic gold concentrate and silver-manganese ore are mixed at a mass ratio of 3:1 and added to a mixing tank containing oxidizing liquid. The slurry concentration is 45%. After being mixed evenly, the mixture is pumped into a ball mill for mechanically enhanced fine grinding until the particle size of -0.045mm accounts for 83%. At the end, the pH value of the slurry is 1.7. Then, the finely ground slurry is subjected to solid-liquid separation to obtain arsenic-removed slag and arsenic-removed liquid. S2. Adjust the arsenic removal slag to a slurry concentration of 18%, and transfer it to a biological oxidation reactor for biological oxidation pretreatment. The oxidation time is 6 days. After the biological oxidation is completed, solid-liquid separation is performed to obtain oxidation slag and oxidation liquid. The oxidation liquid is returned to step S1 for slurry preparation. The oxidation slag enters the cyanidation system to recover gold and silver. S3. After removing impurities such as Fe, As, Cu, and Zn from the arsenic removal solution, manganese is precipitated using ammonium bicarbonate to obtain manganese carbonate product that meets industrial-grade standards. The tail liquid after manganese recovery is returned to step S2 for biological oxidation slurry preparation.

[0044] The multi-element analysis of the manganese carbonate product obtained in Example 2 is shown in Table 4.

[0045] Table 4. Multi-element analysis results of the manganese carbonate product prepared in Example 2 Example 3 This embodiment provides a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore, including the following steps: S1. Mix high-arsenic gold concentrate and silver-manganese ore at a mass ratio of 4:1, add them to a mixing tank containing oxidizing liquid, the slurry concentration is 50%, after mixing evenly, feed them into a ball mill for mechanically enhanced fine grinding, grind to a particle size of -0.045mm accounting for 88%, the pH value of the slurry at the end is 1.5, and then perform solid-liquid separation on the finely ground slurry to obtain arsenic-removed slag and arsenic-removed liquid; S2. Adjust the arsenic removal slag to a slurry concentration of 16%, and transfer it to a biological oxidation reactor for biological oxidation pretreatment. The oxidation time is 5 days. After the biological oxidation is completed, solid-liquid separation is performed to obtain oxidation slag and oxidation liquid. The oxidation liquid is returned to step S1 for slurry preparation. The oxidation slag enters the cyanidation system to recover gold and silver. S3. After removing Fe and As impurities from the arsenic-removing solution, manganese is extracted and recovered using C272 extractant. The manganese-rich solution is then back-extracted and crystallized by evaporation to prepare manganese sulfate. The obtained manganese sulfate product meets industrial-grade standards. The tail liquid after manganese recovery is returned to step S2 for biological oxidation slurry preparation.

[0046] The multi-element analysis of the manganese sulfate product obtained in Example 3 is shown in Table 5.

[0047] Table 5. Multi-element analysis results of the manganese sulfate product prepared in Example 3 Example 4 This embodiment provides a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore, including the following steps: S1. Mix high-arsenic gold concentrate and silver-manganese ore at a mass ratio of 5:1, add them to a mixing tank containing oxidizing liquid, the slurry concentration is 55%, after mixing evenly, feed them into a ball mill for mechanically enhanced fine grinding, grind to a particle size of -0.045mm accounting for 90%, the pH value of the slurry at the end is 1.9, and then perform solid-liquid separation on the finely ground slurry to obtain arsenic-removed slag and arsenic-removed liquid; S2. Adjust the arsenic removal slag to a slurry concentration of 14%, and transfer it to a biological oxidation reactor for biological oxidation pretreatment. The oxidation time is 5 days. After the biological oxidation is completed, solid-liquid separation is performed to obtain oxidation slag and oxidation liquid. The oxidation liquid is returned to step S1 for slurry preparation. The oxidation slag enters the cyanidation system to recover gold and silver. S3. After removing impurities such as Fe, As, Cu, and Zn from the arsenic removal solution, manganese is precipitated using ammonium bicarbonate to obtain manganese carbonate product that meets industrial-grade standards. The tail liquid after manganese recovery is returned to step S2 for biological oxidation slurry preparation.

[0048] The multi-element analysis of the manganese carbonate product obtained in Example 4 is shown in Table 6.

[0049] Table 6. Multi-element analysis results of the manganese carbonate product prepared in Example 4 Example 5 This embodiment provides a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore, including the following steps: S1. Mix high-arsenic gold concentrate and silver-manganese ore at a mass ratio of 2.5:1, add them to a mixing tank containing oxidizing liquid, the slurry concentration is 60%, after mixing evenly, the mixture is pumped into a ball mill for mechanically enhanced fine grinding, grinding to a particle size of -0.045mm accounting for 92%, the pH value of the slurry at the end is 1.8, and then the finely ground slurry is subjected to solid-liquid separation to obtain arsenic-removed slag and arsenic-removed liquid; S2. Adjust the arsenic removal slag to a slurry concentration of 12% and transfer it to a biological oxidation reactor for biological oxidation pretreatment. The oxidation time is 4 days. After the biological oxidation is completed, solid-liquid separation is performed to obtain oxidation slag and oxidation liquid. The oxidation liquid is returned to step S1 for slurry preparation. The oxidation slag enters the cyanidation system to recover gold and silver. S3. After removing Fe and As impurities from the arsenic-removing solution, manganese is extracted and recovered using C272 extractant. The manganese-rich solution is then back-extracted and crystallized by evaporation to prepare manganese sulfate. The obtained manganese sulfate product meets industrial-grade standards. The tail liquid after manganese recovery is returned to step S2 for biological oxidation slurry preparation.

[0050] The multi-element analysis of the manganese sulfate product obtained in Example 5 is shown in Table 7.

[0051] Table 7. Multi-element analysis results of the manganese sulfate product prepared in Example 5. Example 6 This embodiment provides a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore, including the following steps: S1. Mix high-arsenic gold concentrate and silver-manganese ore at a mass ratio of 3.5:1, add them to a mixing tank containing oxidizing liquid, the slurry concentration is 70%, after mixing evenly, the mixture is pumped into a ball mill for mechanically enhanced fine grinding until the particle size of -0.045mm accounts for 95%, the pH value of the slurry at the end is 1.9, and then the finely ground slurry is subjected to solid-liquid separation to obtain arsenic-removed slag and arsenic-removed liquid; S2. Adjust the arsenic removal slag to a slurry concentration of 10%, and transfer it to a biological oxidation reactor for biological oxidation pretreatment. The oxidation time is 4 days. After the biological oxidation is completed, solid-liquid separation is performed to obtain oxidation slag and oxidation liquid. The oxidation liquid is returned to step S1 for slurry preparation. The oxidation slag enters the cyanidation system to recover gold and silver. S3. After removing impurities such as Fe, As, Cu, and Zn from the arsenic removal solution, manganese is precipitated using ammonium bicarbonate to obtain manganese carbonate product that meets industrial-grade standards. The tail liquid after manganese recovery is returned to step S2 for biological oxidation slurry preparation.

[0052] The multi-element analysis of the manganese carbonate product obtained in Example 6 is shown in Table 8.

[0053] Table 8. Multi-element analysis results of the manganese carbonate product prepared in Example 6 As shown in Examples 1-6, this application can stably produce manganese sulfate or manganese carbonate products that meet industrial-grade standards through the synergistic mechanical enhancement reaction of high-arsenic gold concentrate and low-grade silver-manganese ore and subsequent processing. The manganese content of the manganese sulfate product is between 31.40% and 32.10%, and the manganese content of the manganese carbonate product is between 44.20% and 44.80%. The contents of impurities such as iron, arsenic, copper, zinc, and lead in each product are controlled at low levels. Furthermore, with the increase of the proportion of silver-manganese ore and the improvement of the impurity removal process, the manganese content of the product is slightly increased and the impurities are further reduced, which fully verifies the adaptability of the process to raw material fluctuations and the stability of product quality.

[0054] Comparative Example 1 Comparative Example 1 provides a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore. The only difference from Example 1 is that in step S1, the high-arsenic gold concentrate and silver-manganese ore are mixed at a ratio of 2:1 and then directly added to the oxidizing liquid to adjust the slurry. After stirring evenly, solid-liquid separation is carried out without mechanically enhanced fine grinding. Other experimental parameters and conditions are basically the same as those in Example 1, and will not be repeated here.

[0055] Comparative Example 2 Comparative Example 2 provides a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore. The only difference from Example 1 is that the high-arsenic gold concentrate and silver-manganese ore are mixed at a ratio of 2:1 and then directly fed into the biological oxidation system. Other experimental parameters and conditions are basically the same as those in Example 1, and will not be repeated here.

[0056] Comparative Example 3 Comparative Example 3 provides a method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore. Compared with Example 1, the only difference is that in step S1, mechanically enhanced fine grinding only grinds the mixture to -0.045 mm, accounting for 60%. Other experimental parameters and conditions are basically the same as in Example 1, and will not be repeated here.

[0057] The test results of each embodiment and comparative example are shown in Table 9.

[0058] Table 9. Experimental results of each embodiment and comparative example. As shown in Table 9, the arsenic removal rate in the embodiments of this application is above 85%, the manganese leaching rate is above 93%, the gold recovery rate is stable above 91%, and the silver recovery rate exceeds 86%, fully verifying the superiority of the synergistic process of mechanically enhanced fine grinding and subsequent biological oxidation in this application. With the increase of the silver-manganese ore ratio and the increase of grinding fineness, the manganese leaching rate and gold and silver recovery rates show an upward trend, indicating that the process has good adaptability to different raw material conditions. Comparative Example 1, due to the lack of mechanically enhanced fine grinding and only simple mixing and slurry preparation followed by solid-liquid separation, had an arsenic removal rate of only 64.46% and a manganese leaching rate of only 78.02%, far lower than Example 1, resulting in a still high arsenic load in the subsequent biological oxidation stage, and significantly lower gold and silver recovery rates. Comparative Example 2 directly introduced the high-arsenic gold concentrate and silver-manganese ore into the biological oxidation system without any chemical arsenic removal treatment. During the biological oxidation process, the high concentration of arsenic ions severely inhibited microbial activity, resulting in a gold recovery rate of only 63.87% and a silver recovery rate of only 75.42%, indicating that this method cannot effectively treat high-arsenic materials. Although Comparative Example 3 underwent mechanically enhanced fine grinding, the grinding fineness was insufficient, and the arsenic removal rate and manganese leaching rate were only 78.05% and 84.27%, respectively. The gold and silver recovery rates were also lower than those of Example 1.

[0059] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.

Claims

1. A method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore, characterized in that, Includes the following steps: S1. High-arsenic gold concentrate and silver-manganese ore are mixed in a certain proportion, and an oxidizing liquid is added to adjust the slurry concentration to 40-70%. Mechanical fine grinding is carried out in an acid-resistant ball mill until the particle size of -0.045mm accounts for 80-95%. During the fine grinding process, in the presence of the oxidizing liquid, pyrolusite in the silver-manganese ore and arsenopyrite in the high-arsenic gold concentrate undergo a redox reaction. Arsenic and iron enter the liquid phase in ionic form, while sulfur remains in the slag in elemental form. After the fine grinding is completed, solid-liquid separation is performed to obtain arsenic-removed slag and arsenic-removed liquid. S2. The arsenic removal slag is subjected to biological oxidation pretreatment, followed by solid-liquid separation to obtain oxidation slag and oxidation liquid; the oxidation liquid is returned to step S1 for slurry preparation; the oxidation slag is fed into the cyanidation system to recover gold and silver; S3. After the arsenic removal liquid is treated to remove impurities, the manganese in it is recovered to obtain manganese salt product; the tail liquid after manganese recovery is returned to step S2 for biological oxidation slurry preparation.

2. The method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore according to claim 1, characterized in that, In step S1, the mass ratio of the high-arsenic gold concentrate to the silver-manganese ore is (2~5):

1.

3. The method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore according to claim 2, characterized in that, In the silver-manganese ore, manganese exists in the form of pyrolusite, with a manganese grade of 8-30%.

4. The method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore according to claim 1, characterized in that, In step S1, the pH value of the slurry is less than 2 after mechanically enhanced fine grinding.

5. The method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore according to claim 1, characterized in that, In step S2, the slurry concentration of the bio-oxidation pretreatment is 10-18%, and the oxidation time is 4-6 days.

6. The method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore according to claim 5, characterized in that, The bacterial strains used in the biological oxidation pretreatment are one or more of the following: thiobacillus ferrooxidans, thiobacillus thiooxidans, thiobacillus ferrooxidans, and Leptospira ferrooxidans.

7. The method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore according to claim 1, characterized in that, In step S3, the method for recovering manganese from the arsenic removal solution is as follows: first remove impurities, and then use an extraction-back-extraction-evaporation crystallization process to prepare manganese sulfate product; or first remove impurities, and then use a precipitation-washing-drying process to prepare manganese carbonate product.

8. The method for the synergistic resource utilization of high-arsenic gold concentrate and low-grade silver-manganese ore according to claim 1, characterized in that, In step S1, the fineness of the high-arsenic gold concentrate is 80-95% for materials with a fineness of -0.074mm; the fineness of the silver-manganese ore is 70-85% for materials with a fineness of -0.074mm.

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