A comprehensive recovery method for valuable components of arsenic-containing gold pyrite

Abstract

The present invention relates to a comprehensive recovery method for valuable components of arsenic-containing gold-pyrite, comprising the following steps: (1) classification of materials to be processed; (2) microwave roasting; (3) high-temperature oxidation rinsing of roasted slag; (4) recovery of copper from the rinsing liquid; (5) alkaline leaching pretreatment of the rinsing slag; and (6) carbon-based leaching of the alkaline leached slag. The present invention can efficiently achieve comprehensive utilization of the valuable components of arsenic-containing gold-pyrite, achieving a gold, silver, and sulfur recovery rate exceeding 90%, and a copper recovery rate reaching 86%. Furthermore, high-quality iron concentrate can be obtained, with strong comprehensive recovery and processing capabilities and stable production indicators. The method can be widely used for the comprehensive recovery and processing of ores such as arsenic-encapsulated pyrite, sulfur concentrate, iron concentrate, and gold concentrate, and has important industrial application value.

Description

Technical Field

[0001] The invention belongs to the technical field of metallurgy, and in particular relates to a comprehensive recovery method for valuable components of arsenic-gold pyrite. Background Art

[0002] As the grade of gold ore in mines continues to decline, low-grade, difficult-to-process gold ores have gradually become a hot topic of research in the gold industry. Encapsulated gold ores are the most common type of difficult-to-process gold ore. In this type of ore, gold is often encapsulated in sulfide minerals as fine impregnations, resulting in low cyanide leaching rates. Furthermore, the ore contains other metals, resulting in an extremely complex distribution pattern, making its comprehensive development and utilization a challenge for the industry. When gold coexists with non-ferrous metals such as copper, leaching significantly increases cyanide consumption, resulting in high production costs and low recovery rates. Furthermore, arsenic in the ore often exists as an isomorphous substance within the pyrite crystal structure, making it difficult to remove. This seriously affects the quality of the subsequent iron ore concentrate and poses safety risks.

[0003] Therefore, in recent years, extensive and in-depth research has been conducted both domestically and internationally on pretreatment technologies for refractory gold ores containing finely encapsulated arsenic. Currently, several pretreatment methods exist, including oxidative roasting, pressure oxidation, and biological oxidation. While these techniques differ, they all aim to break open minerals like pyrite and arsenopyrite, exposing the gold and thereby increasing its leaching rate.

[0004] The biological oxidation method uses certain sulfur-iron oxidizing microorganisms to decompose oxidized minerals, thereby improving the recovery of encapsulated difficult-to-treat minerals. It has the advantages of low equipment cost, no arsenic-containing flue gas and good mineral treatment effect. However, this method has low treatment efficiency, especially for minerals with low arsenic content, the oxidation and decomposition rate is slow, which restricts its further development.

[0005] The pressure oxidation method dissociates sulfide minerals under high temperature and high pressure conditions, exposing the encapsulated gold particles, thereby achieving the purpose of improving gold recovery. It has the advantages of high recovery rate and stable leaching residue. However, this method requires extremely high equipment investment and high production costs, and basic research on pressure oxidation is relatively lacking.

[0006] While the widely used oxidation roasting method boasts mature technology and high throughput, it also suffers from high energy consumption, unstable slag, and susceptibility to sintering. Metal recovery is particularly low for fine-grained ores and those coated with multiple metals. Amidst resource constraints and increasingly challenging environmental conditions, this process has also encountered several urgent challenges with arsenic-gold coated pyrite ores, including the following:

[0007] (1) Fine-grained minerals are easily sintered, resulting in low recovery rates of valuable metals.

[0008] (2) The arsenic in pyrite is partially present in the form of a homogeneous species in the pyrite crystals, and some is present in arsenopyrite. Most of the arsenopyrite exists in the form of a single substance, a small part is associated with or encapsulated by pyrite, and a small part is encapsulated by gangue. During the roasting process, the arsenic originally present in the pyrite crystals is converted into ferric arsenate and encapsulated by the generated iron oxide. The arsenic in the arsenopyrite is partially converted into arsenic trioxide, and some is converted into ferric arsenate and encapsulated by iron oxide and gangue. The encapsulated arsenic is difficult to remove, seriously affecting the quality of the subsequent iron concentrate.

[0009] (3) Poor adaptability, poor processing effect on fine particles and encapsulated ores, seriously affecting the recovery of valuable metals.

[0010] Based on the above problems, the present invention proposes a comprehensive recovery method for valuable components of arsenic-containing gold pyrite to overcome the current shortcomings and problems, improve the recovery rate of valuable components in difficult-to-treat minerals, realize comprehensive utilization of resources, and enhance the economic and social benefits of the enterprise. Summary of the Invention

[0011] In view of the above problems, the present invention provides a comprehensive recovery method for valuable components of arsenic-containing gold pyrite.

[0012] The specific technical solution is: a comprehensive recovery method for valuable components of arsenic-containing gold pyrite, comprising the following steps:

[0013] (1) Classification of materials to be processed: The materials to be processed are transported to the air classifier for classification treatment to obtain materials with particle sizes of -0.074mm to +0.025mm and -0.025mm. Since pyrites of different particle sizes have different ignition points, the materials are divided into two particle size products, so that different roasting conditions can be adopted in the subsequent process to avoid sintering of fine-grained materials.

[0014] (2) Microwave roasting: The two products obtained in step (1) are respectively transported to different microwave ovens for roasting, wherein the roasting temperature of the -0.074 mm to +0.025 mm particle size material is 550 to 680 ° C, and the roasting time is 2 to 3 h, and the roasting temperature of the -0.025 mm particle size material is 450 to 500 ° C, and the roasting time is 1 to 2 h. After roasting, both particle size materials produce roasting slag and sulfur dioxide fume (for sulfuric acid production);

[0015] Since microwaves have the characteristics of directly heating the inside of an object evenly and selectively, sintering is less likely to occur when using microwave ovens. During the heating process, sulfur and arsenic, which have larger dielectric constants, will evaporate and burn first, causing a large number of cavities and cracks in the mineral particles. In addition, the uniform heating can also convert arsenic into arsenic trioxide as much as possible and escape with sulfur dioxide smoke, reducing the possibility of conversion into ferric arsenate and creating favorable conditions for subsequent dissociation.

[0016] (3) High-temperature oxidation rinsing of roasted slag: The roasted slag obtained in step (2) at a temperature of 300 to 400°C is transported to a rinsing system for rinsing, and then filtered to obtain rinsed slag and rinsing liquid;

[0017] The rinsing process involves adding a clear liquid to the high-temperature roasted slag (300-400°C), causing the slag to cool suddenly and generate greater structural stress, breaking it into fine particles. This opens the package, allowing the sulfide minerals to fully dissociate and expose the encapsulated gold particles.

[0018] (4) Recovering copper from the rinse liquid: The rinse liquid obtained in step (3) is transported to a stirring barrel, a copper precipitant is added, and the mixture is stirred and slurried for 30 minutes before filtering to obtain a copper product and waste liquid, which is then sent to a waste liquid treatment system;

[0019] (5) Alkali leaching pretreatment of rinse residue: The rinse residue obtained in step (3) is subjected to alkaline leaching pretreatment, and sodium hydroxide and sodium sulfide are added to obtain alkaline leaching residue with extremely low arsenic content and arsenic-containing alkaline leaching solution, and the arsenic-containing alkaline leaching solution is transported to the arsenic removal system;

[0020] This step utilizes the synergistic effect of sodium hydroxide and sodium sulfide to leach most of the arsenic in the rinsing slag (iron oxide), thereby improving the quality of the iron concentrate.

[0021] (6) Extracting gold and silver by carbon-based leaching of alkali leaching residue: The alkali leaching residue obtained in step (5) is subjected to carbon-based leaching to extract gold and silver, thereby obtaining gold-loaded activated carbon and high-quality iron ore concentrate.

[0022] Furthermore, in step (3), the liquid-to-solid ratio during rinsing is 2.5:1, and the slurry preparation time is 20 to 30 minutes.

[0023] Furthermore, during rinsing in step (3), 0.8 to 1 kg / t of manganese dioxide is added to convert the residual iron sulfide and silver sulfide into oxides, and to convert the divalent iron into trivalent iron precipitate.

[0024] Furthermore, in step (3), sodium hydroxide is added after the manganese dioxide reacts to adjust the pH value of the rinse solution to 3 to 5.4.

[0025] Furthermore, the copper precipitant in step (4) is sodium hydrosulfide, sodium sulfide or thioacetamide.

[0026] Furthermore, the copper precipitant is added in an amount of 1.1 to 1.2 times the theoretical amount.

[0027] Furthermore, during the alkaline leaching pretreatment in step (5), 15-20 kg / t of sodium hydroxide and 1-2 kg / t of sodium sulfide are added, the liquid-solid ratio is 1.5:1, the reaction temperature is 70° C., and the leaching time is 2-3 h.

[0028] Furthermore, in step (6), when gold and silver are extracted by carbon leaching, the liquid-solid ratio is 2:1, the pH value is controlled at 10.5-11.5, the free cyanide concentration in the ore pulp is adjusted to 0.6‰-1‰ with sodium cyanide, the activated carbon is 15-30 g / L, and the leaching time is 32 h.

[0029] Beneficial effects of the present invention:

[0030] In terms of specific process methods, the present invention separates the material into different particle sizes based on the different ignition points of pyrite ores of varying particle sizes. Appropriate microwave roasting conditions are then applied to the material. This prevents sintering of fine particles while allowing sulfur and arsenic, which have higher dielectric constants, to combust and volatilize first. This creates numerous cavities and cracks, facilitating fragmentation and dissociation during rinsing, fully exposing the encapsulated gold particles and improving gold recovery. Furthermore, during rinsing, manganese dioxide is used to convert residual iron sulfide and silver sulfide into oxides, and ferrous iron is converted into ferric iron for precipitation, creating favorable conditions for the subsequent separation of valuable components. During the alkaline leaching pretreatment of the rinsing residue, the synergistic effect of sodium hydroxide and sodium sulfide is cleverly utilized to leach the majority of the arsenic in the rinsing residue (iron oxide), thereby improving the quality of the iron concentrate.

[0031] It can be seen from the examples that the present invention can efficiently realize the comprehensive utilization of valuable components of arsenic-containing gold pyrite, with the recovery rates of gold, silver and sulfur reaching more than 90%, and the copper recovery rate reaching 86%. In addition, high-quality iron concentrate can be obtained, and the comprehensive recovery and processing capacity is strong and the production indicators are stable. It can be widely used in the comprehensive recovery and processing of ores such as arsenic-encapsulated pyrite, sulfur concentrate, iron concentrate and gold concentrate, and has important industrial promotion and application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a flow chart of the method of the present invention; DETAILED DESCRIPTION

[0033] In order to make the technical problems and technical solutions solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. Example 1

[0034] Raw material 1#: an arsenic-gold pyrite, the valuable elements of which are mainly Au, Ag, Fe, Cu and S, with grades of 2.29g / t, 26.04g / t, 40.35%, 0.11% and 45.25% respectively; the harmful element is mainly arsenic, with a grade of 0.21%; the gold in the pyrite is mainly present in the form of gold inclusions, accounting for 56.6%, of which metal sulfide inclusions account for 51.95% and gangue inclusions account for 4.65%; silver is mainly present in the form of silver inclusions, accounting for 79.80%; iron is mainly present in the form of pyrite and pyrrhotite, accounting for 85.55%, followed by hematite and magnetite; copper is present in the form of chalcopyrite; arsenic is mainly present in pyrite and arsenopyrite; the gangue minerals are mainly quartz and feldspar.

[0035] like Figure 1 As shown, the present invention is implemented on the arsenic-containing gold pyrite, and the specific steps are as follows:

[0036] (1) Classification of materials to be processed: The materials to be processed are transported to the air classifier for classification to obtain materials with particle sizes of -0.074mm to +0.025mm and -0.025mm;

[0037] (2) Microwave roasting: The two products obtained in step (1) are respectively transported to different microwave ovens for roasting, wherein the roasting temperature of the -0.074 mm to +0.025 mm particle size material is 550 to 680 ° C, and the roasting time is 3 h, and the roasting temperature of the -0.025 mm particle size material is 450 to 500 ° C, and the roasting time is 2 h. After roasting, both particle size materials produce roasting slag and sulfur dioxide fume (for sulfuric acid production);

[0038] (3) High-temperature oxidation rinsing of roasted slag: The roasted slag obtained in step (2) at a temperature of 300-400°C is transported to a rinsing system for rinsing, and then filtered to obtain the rinsed slag and rinsing liquid; during rinsing, the liquid-to-solid ratio is 2.5:1, and the slurry mixing time is 30 minutes; 1 kg / t of manganese dioxide is also added during rinsing to convert the residual iron sulfide and silver sulfide into oxides using manganese dioxide, and to convert divalent iron into trivalent iron precipitation; sodium hydroxide is added after the manganese dioxide reaction to adjust the pH value of the rinsing liquid to 3-5.4.

[0039] (4) Recovering copper from the rinse liquid: The rinse liquid obtained in step (3) is transported to a stirring barrel, and a copper precipitant (sodium hydrosulfide is used, and the amount is 1.2 times the theoretical amount) is added. After stirring and slurrying for 30 minutes, the copper product and waste liquid are obtained by filtering. The waste liquid is then sent to a waste liquid treatment system;

[0040] (5) Alkali leaching pretreatment of rinse residue: The rinse residue obtained in step (3) is subjected to alkaline leaching pretreatment by adding 20 kg / t of sodium hydroxide and 2 kg / t of sodium sulfide, with a liquid-to-solid ratio of 1.5:1, a temperature of 70°C, and a leaching time of 3 h to obtain alkaline leaching residue with extremely low arsenic content and arsenic-containing alkaline leaching solution, which is transported to the arsenic removal system;

[0041] (6) Extracting gold and silver from alkaline leaching residue by carbon-based leaching: The alkaline leaching residue obtained in step (5) is subjected to carbon-based leaching to extract gold and silver. When extracting gold and silver by carbon-based leaching, the liquid-solid ratio is 2:1, the pH value is controlled at 10.5-11.5, the free cyanide concentration in the slurry is adjusted to 0.6‰-1‰ with sodium cyanide, the activated carbon is 30 g / L, and the leaching time is 32 h to obtain gold-loaded activated carbon and high-quality iron ore concentrate.

[0042] The arsenic-containing gold pyrite of the present invention was used to implement the test results: the gold recovery rate reached 92.45%, the silver recovery rate reached 90.52%, the sulfur recovery rate reached 99.2%, and the copper recovery rate reached 86.23%; high-quality iron concentrate was obtained, with a grade of 64.23%, an arsenic content reduced to 0.018%, and an iron recovery rate of 96.12%. Example 2

[0043] Raw material 2#: an arsenic-gold pyrite, the valuable elements of which are mainly Au, Ag, Fe, Cu and S, with grades of 2.18g / t, 25.34g / t, 41.05%, 0.12% and 45.15% respectively; the harmful element is mainly arsenic, with a grade of 0.23%; the gold in the pyrite is mainly present in the form of gold inclusions, accounting for 57.5%, of which metal sulfide inclusions account for 52.05% and gangue inclusions account for 5.45%; silver is mainly present in the form of silver inclusions, accounting for 79.76%; iron is mainly present in the form of pyrite and pyrrhotite, accounting for 86.15%, followed by hematite and magnetite; copper is present in the form of chalcopyrite; arsenic is mainly present in pyrite and arsenopyrite; the gangue minerals are mainly quartz and feldspar.

[0044] like Figure 1 As shown, the present invention is implemented on the arsenic-containing gold pyrite, and the specific steps are as follows:

[0045] (1) Classification of materials to be processed: The materials to be processed are transported to the air classifier for classification to obtain materials with particle sizes of -0.074mm to +0.025mm and -0.025mm;

[0046] (2) Microwave roasting: The two products obtained in step (1) are respectively transported to different microwave ovens for roasting, wherein the roasting temperature of the -0.074 mm to +0.025 mm particle size material is 550 to 680 ° C, and the roasting time is 2 h, and the roasting temperature of the -0.025 mm particle size material is 450 to 500 ° C, and the roasting time is 2 h. After roasting, both particle size materials produce roasting slag and sulfur dioxide fume (for sulfuric acid production);

[0047] (3) High-temperature oxidation rinsing of roasted slag: The roasted slag obtained in step (2) at a temperature of 300-400°C is transported to a rinsing system for rinsing, and then filtered to obtain rinsed slag and rinsing liquid; during rinsing, the liquid-to-solid ratio is 2.5:1, and the slurry mixing time is 20 minutes; 0.8 kg / t of manganese dioxide is also added during rinsing to convert the residual iron sulfide and silver sulfide into oxides using manganese dioxide, and to convert divalent iron into trivalent iron precipitation; sodium hydroxide is added after the manganese dioxide reaction to adjust the pH value of the rinsing liquid to 3-5.4.

[0048] (4) Recovering copper from the rinse liquid: The rinse liquid obtained in step (3) is transported to a stirring barrel, and a copper precipitant (sodium sulfide is used, and the amount is 1.1 times the theoretical amount) is added. After stirring and slurrying for 30 minutes, the copper product and waste liquid are obtained by filtering. The waste liquid is then sent to a waste liquid treatment system;

[0049] (5) Alkali leaching pretreatment of rinse residue: The rinse residue obtained in step (3) is subjected to alkaline leaching pretreatment by adding 15 kg / t of sodium hydroxide and 1 kg / t of sodium sulfide, with a liquid-to-solid ratio of 1.5:1, a temperature of 70°C, and a leaching time of 2 h to obtain alkaline leaching residue with extremely low arsenic content and arsenic-containing alkaline leaching solution, which is transported to the arsenic removal system;

[0050] (6) Extracting gold and silver by carbon-based leaching of alkali leaching residue: The alkali leaching residue obtained in step (5) is subjected to carbon-based leaching to extract gold and silver. When extracting gold and silver by carbon-based leaching, the liquid-solid ratio is 2:1, the pH value is controlled at 10.5-11.5, the free cyanide concentration in the ore pulp is adjusted to 0.6‰-1‰ with sodium cyanide, the activated carbon is 15 g / L, and the leaching time is 32 h to obtain gold-loaded activated carbon and high-quality iron ore concentrate.

[0051] The arsenic-containing gold pyrite of the present invention was used to implement the test results: the gold recovery rate reached 92.13%, the silver recovery rate reached 90.24%, the sulfur recovery rate reached 99.21%, and the copper recovery rate reached 86.31%; high-quality iron concentrate was obtained, with a grade of 64.34%, an arsenic content reduced to 0.018%, and an iron recovery rate of 96.51%. Example 3

[0052] Raw material 3#: an arsenic-gold pyrite, the valuable elements of which are mainly Au, Ag, Fe, Cu and S, with grades of 2.31g / t, 26.24g / t, 40.75%, 0.13% and 45.57% respectively; the harmful element is mainly arsenic, with a grade of 0.22%; gold in pyrite mainly exists in the form of gold inclusions, with a proportion of 56.7%, of which metal sulfide inclusions account for 51.87% and gangue inclusions account for 4.93%; silver mainly exists in the form of silver inclusions, with a proportion of 79.66%; iron mainly exists in the form of pyrite and pyrrhotite, with a proportion of 85.65%, followed by hematite and magnetite; copper exists in the form of chalcopyrite; arsenic mainly exists in pyrite and arsenopyrite; gangue minerals are mainly quartz and feldspar.

[0053] like Figure 1 As shown, the present invention is implemented on the arsenic-containing gold pyrite, and the specific steps are as follows:

[0054] (1) Classification of materials to be processed: The materials to be processed are transported to the air classifier for classification to obtain materials with particle sizes of -0.074mm to +0.025mm and -0.025mm;

[0055] (2) Microwave roasting: The two products obtained in step (1) are respectively transported to different microwave ovens for roasting, wherein the roasting temperature of the -0.074 mm to +0.025 mm particle size material is 550 to 680 ° C, and the roasting time is 2.5 h, and the roasting temperature of the -0.025 mm particle size material is 450 to 500 ° C, and the roasting time is 1.5 h. After roasting, both particle size materials produce roasting slag and sulfur dioxide flue gas (for sulfuric acid production);

[0056] (3) High-temperature oxidation rinsing of roasted slag: The roasted slag obtained in step (2) at a temperature of 300-400°C is transported to a rinsing system for rinsing, and then filtered to obtain the rinsed slag and rinsing liquid; during rinsing, the liquid-to-solid ratio is 2.5:1, and the slurry mixing time is 25 minutes; 1 kg / t of manganese dioxide is also added during rinsing to convert the residual iron sulfide and silver sulfide into oxides using manganese dioxide, and to convert divalent iron into trivalent iron precipitation; sodium hydroxide is added after the manganese dioxide reaction to adjust the pH value of the rinsing liquid to 3-5.4.

[0057] (4) Recovering copper from the rinse liquid: The rinse liquid obtained in step (3) is transported to a stirring barrel, and a copper precipitant (sodium hydrosulfide is used, and the amount is 1.1 times the theoretical amount) is added. After stirring and slurrying for 30 minutes, the copper product and waste liquid are obtained by filtering. The waste liquid is then sent to a waste liquid treatment system;

[0058] (5) Alkali leaching pretreatment of rinse residue: The rinse residue obtained in step (3) is subjected to alkaline leaching pretreatment by adding 20 kg / t of sodium hydroxide and 1.5 kg / t of sodium sulfide, with a liquid-to-solid ratio of 1.5:1, a temperature of 70°C, and a leaching time of 2.5 h to obtain alkaline leaching residue with extremely low arsenic content and arsenic-containing alkaline leaching solution, which is transported to the arsenic removal system;

[0059] (6) Extracting gold and silver by carbon-based leaching of alkali leaching residue: The alkali leaching residue obtained in step (5) is subjected to carbon-based leaching to extract gold and silver. When extracting gold and silver by carbon-based leaching, the liquid-solid ratio is 2:1, the pH value is controlled at 10.5-11.5, the free cyanide concentration in the ore pulp is adjusted to 0.6‰-1‰ with sodium cyanide, the activated carbon is 20 g / L, and the leaching time is 32 h to obtain gold-loaded activated carbon and high-quality iron ore concentrate.

[0060] The arsenic-containing gold pyrite of the present invention was used to implement the test results: the gold recovery rate reached 92.46%, the silver recovery rate reached 90.43%, the sulfur recovery rate reached 99.36%, and the copper recovery rate reached 85.97%; high-quality iron concentrate was obtained, with a grade of 64.23%, an arsenic content reduced to 0.019%, and an iron recovery rate of 96.48%. Example 4

[0061] Raw material 4#: an arsenic-gold pyrite, the valuable elements of which are mainly Au, Ag, Fe, Cu and S, with grades of 2.33g / t, 25.97g / t, 41.05%, 0.11% and 45.47% respectively; the harmful element is mainly arsenic, with a grade of 0.22%; gold in the pyrite mainly exists in the form of gold inclusions, accounting for 57.1%, of which metal sulfide inclusions account for 51.65% and gangue inclusions account for 5.45%; silver mainly exists in the form of silver inclusions, accounting for 79.78%; iron mainly exists in the form of pyrite and pyrrhotite, accounting for 86.25%, followed by hematite and magnetite; copper exists in the form of chalcopyrite; arsenic mainly exists in pyrite and arsenopyrite; gangue minerals are mainly quartz and feldspar.

[0062] like Figure 1 As shown, the present invention is implemented on the arsenic-containing gold pyrite, and the specific steps are as follows:

[0063] (1) Classification of materials to be processed: The materials to be processed are transported to the air classifier for classification to obtain materials with particle sizes of -0.074mm to +0.025mm and -0.025mm;

[0064] (2) Microwave roasting: The two products obtained in step (1) are respectively transported to different microwave ovens for roasting, wherein the roasting temperature of the -0.074 mm to +0.025 mm particle size material is 550 to 680 ° C, and the roasting time is 3 h, and the roasting temperature of the -0.025 mm particle size material is 450 to 500 ° C, and the roasting time is 2 h. After roasting, both particle size materials produce roasting slag and sulfur dioxide fume (for sulfuric acid production);

[0065] (3) High-temperature oxidation rinsing of roasted slag: The roasted slag obtained in step (2) at a temperature of 300-400°C is transported to a rinsing system for rinsing, and then filtered to obtain the rinsed slag and rinsing liquid; during rinsing, the liquid-to-solid ratio is 2.5:1, and the slurry mixing time is 25 minutes; 0.8 kg / t of manganese dioxide is also added during rinsing to convert the residual iron sulfide and silver sulfide into oxides using manganese dioxide, and to convert divalent iron into trivalent iron precipitation; sodium hydroxide is added after the manganese dioxide reaction to adjust the pH value of the rinsing liquid to 3-5.4.

[0066] (4) Recovering copper from the rinse liquid: The rinse liquid obtained in step (3) is transported to a stirring barrel, and a copper precipitant (thioacetamide is used, and the amount is added according to 1.2 times the theoretical amount) is added. After stirring and slurrying for 30 minutes, it is filtered to obtain a copper product and waste liquid, and the waste liquid is sent to a waste liquid treatment system;

[0067] (5) Alkali leaching pretreatment of rinse residue: The rinse residue obtained in step (3) is subjected to alkaline leaching pretreatment by adding 20 kg / t of sodium hydroxide and 1.5 kg / t of sodium sulfide, with a liquid-to-solid ratio of 1.5:1, a temperature of 70°C, and a leaching time of 3 h to obtain alkaline leaching residue with extremely low arsenic content and arsenic-containing alkaline leaching solution, which is transported to the arsenic removal system;

[0068] (6) Extracting gold and silver by carbon-based leaching of alkali leaching residue: The alkali leaching residue obtained in step (5) is subjected to carbon-based leaching to extract gold and silver. When extracting gold and silver by carbon-based leaching, the liquid-solid ratio is 2:1, the pH value is controlled at 10.5-11.5, the free cyanide concentration in the ore pulp is adjusted to 0.6‰-1‰ with sodium cyanide, the activated carbon is 25 g / L, and the leaching time is 32 h to obtain gold-loaded activated carbon and high-quality iron ore concentrate.

[0069] The arsenic-containing gold pyrite of the present invention was used to implement the test results: the gold recovery rate reached 91.98%, the silver recovery rate reached 90.54%, the sulfur recovery rate reached 99.45%, and the copper recovery rate reached 86.78%; high-quality iron concentrate was obtained, with a grade of 64.35%, an arsenic content reduced to 0.018%, and an iron recovery rate of 96.46%.

[0070] In summary, this method, when used to treat this type of encapsulated arsenic-bearing gold-pyrite ore, achieved gold recovery rates of 92%, silver recovery rates of 90%, sulfur recovery rates of 99%, and copper recovery rates of 86%. High-quality iron concentrate was obtained, with a grade of 64%, an arsenic content reduced to 0.019%, and an iron recovery rate of 96%. This process demonstrates its strong applicability and stable production performance, enabling efficient and comprehensive utilization of arsenic-bearing gold-pyrite ore. It can also be used for the comprehensive recovery and treatment of arsenic-bearing encapsulated sulfur concentrate, iron concentrate, and gold concentrate, thus possessing significant industrial application value.

[0071] The present invention is described in detail above through specific and preferred embodiments, but those skilled in the art should understand that the present invention is not limited to the embodiments described above. Any modifications, equivalent substitutions, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A comprehensive recovery method for valuable components of arsenic-containing gold pyrite, characterized in that: The steps include: (1) Classification of materials to be processed: The materials to be processed are transported to the air classifier for classification to obtain materials with particle sizes of -0.074mm to +0.025mm and -0.025mm; (2) Microwave roasting: The two products obtained in step (1) are respectively transported to different microwave ovens for roasting, wherein the roasting temperature of the -0.074 mm to +0.025 mm particle size material is 550 to 680 ° C, and the roasting time is 2 to 3 h, and the roasting temperature of the -0.025 mm particle size material is 450 to 500 ° C, and the roasting time is 1 to 2 h. After roasting, roasting slag and sulfur dioxide flue gas are obtained for both particle size materials; (3) High-temperature oxidation rinsing of roasted slag: The roasted slag obtained in step (2) at a temperature of 300 to 400°C is transported to a rinsing system for rinsing, and then filtered to obtain rinsed slag and rinsing liquid; (4) Recovering copper from the rinse liquid: The rinse liquid obtained in step (3) is transported to a stirring barrel, a copper precipitant is added, and the mixture is stirred and slurried for 30 minutes before filtering to obtain a copper product and waste liquid, which is then sent to a waste liquid treatment system; (5) Alkali leaching pretreatment of rinse residue: The rinse residue obtained in step (3) is subjected to alkaline leaching pretreatment, and sodium hydroxide and sodium sulfide are added to obtain alkaline leaching residue with extremely low arsenic content and arsenic-containing alkaline leaching solution, and the arsenic-containing alkaline leaching solution is transported to the arsenic removal system; (6) Extracting gold and silver by carbon-based leaching of alkali leaching residue: The alkali leaching residue obtained in step (5) is subjected to carbon-based leaching to extract gold and silver, thereby obtaining gold-loaded activated carbon and high-quality iron ore concentrate.

2. The method for comprehensive recovery of valuable components from arsenic-containing gold pyrite according to claim 1, characterized in that: In step (3), the liquid-to-solid ratio during rinsing is 2.5:1, and the slurry preparation time is 20 to 30 minutes.

3. The method for comprehensive recovery of valuable components from arsenic-containing gold pyrite according to claim 2, characterized in that: During rinsing in step (3), 0.8-1 kg / t of manganese dioxide is also added to convert the residual iron sulfide and silver sulfide into oxides, and to convert the divalent iron into trivalent iron precipitation.

4. The method for comprehensive recovery of valuable components from arsenic-containing gold pyrite according to claim 3, characterized in that: Step (3) After the manganese dioxide reacts, sodium hydroxide is added to adjust the pH value of the rinse solution to 3 to 5.

4.

5. The method for comprehensive recovery of valuable components from arsenic-containing gold pyrite according to claim 1, characterized in that: The copper precipitant in step (4) is sodium hydrosulfide, sodium sulfide or thioacetamide.

6. The method for comprehensive recovery of valuable components from arsenic-containing gold pyrite according to claim 5, characterized in that: The copper precipitant is added in an amount of 1.1 to 1.2 times the theoretical amount.

7. The method for comprehensive recovery of valuable components from arsenic-containing gold pyrite according to claim 1, characterized in that: During the alkaline leaching pretreatment in step (5), 15-20 kg / t of sodium hydroxide and 1-2 kg / t of sodium sulfide are added, the liquid-solid ratio is 1.5:1, the reaction temperature is 70°C, and the leaching time is 2h-3h.

8. The method for comprehensive recovery of valuable components from arsenic-containing gold pyrite according to claim 1, characterized in that: When gold and silver are extracted by carbon leaching in step (6), the liquid-solid ratio is 2:1, the pH value is controlled at 10.5-11.5, the free cyanide concentration in the ore pulp is adjusted to 0.6‰-1‰ with sodium cyanide, the activated carbon is 15-30 g / L, and the leaching time is 32 h.

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