Comprehensive recovery method for valuable components of arsenic-containing gold pyrite

Abstract

The invention relates to a comprehensive recovery method for valuable components of arsenic-containing gold pyrite. The method comprises the following steps: (1) grading materials to be treated; (2) microwave roasting; (3) performing high-temperature oxidation rinsing on the roasting slag; (4) recovering copper from the rinsing liquid; (5) carrying out alkaline leaching pretreatment on the rinsing residues; and (6) extracting gold and silver from alkaline leaching residues by a carbon leaching method. According to the method, valuable components of the arsenic-containing gold pyrite can be efficiently and comprehensively utilized, the recovery rate of gold, silver and sulfur reaches 90% or above, the recovery rate of copper reaches 86%, high-quality iron ore concentrate can be obtained, the comprehensive recovery treatment capacity is high, production indexes are stable, and the method is suitable for industrial production. The method can be widely applied to comprehensive recovery treatment of ores such as arsenic-containing wrapped pyrite, sulfur concentrate, iron ore concentrate and gold concentrate, and has important industrial popularization and 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 decrease, low-grade and difficult-to-process gold mines have gradually become a hot topic in the gold industry. Encapsulated gold mines are the most common difficult-to-process gold mines. In such ores, gold is often encapsulated in sulfide minerals in the form of fine impregnation, resulting in a low cyanide leaching rate. At the same time, the ore contains other metals, and the occurrence state is extremely complex. Its comprehensive development and utilization is a difficult problem in the industry. When gold coexists with non-ferrous metals such as copper, leaching will greatly increase the consumption of cyanide, which not only has high production costs, but also low recovery rates. In addition, arsenic in the ore often exists in the crystal structure of pyrite in the form of "isomorphism", which is difficult to remove, seriously affecting the quality of subsequent iron concentrates, and there are also safety hazards.

[0003] Therefore, in recent years, both at home and abroad, extensive and far-reaching research has been conducted on the pretreatment technology of arsenic-containing fine-encapsulated refractory gold ores. Currently, there are pretreatment methods such as oxidation roasting, pressure oxidation and biological oxidation. Although these process technologies are different, their purpose is to open the encapsulation of minerals such as pyrite and arsenopyrite to expose the gold, thereby increasing the gold 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 better 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 is to dissociate sulfide minerals under high temperature and high pressure conditions to expose the encapsulated gold particles, thereby achieving the purpose of improving the gold recovery rate. It has the advantages of high recovery rate and stable leaching residue. However, this method has extremely high equipment investment and high production cost, and there is a lack of basic research on pressure oxidation.

[0006] The widely used oxidation roasting method has the advantages of mature technology and large processing capacity, but it has the problems of high energy consumption, unstable roasting slag, and easy sintering. Especially for fine particles and multi-metal encapsulated ores, the metal recovery rate is very low. Under the situation of resource shortage and increasingly severe environmental situation, this process has also encountered some problems for some arsenic-gold encapsulated pyrite ores that need to be solved urgently, as follows: (1) Fine-grained minerals are easily sintered, resulting in low recovery rates of valuable metals.

[0007] (2) Part of the arsenic in pyrite exists in the form of a homogeneous image in the crystals of pyrite, and part of it exists in arsenopyrite. Most of the arsenopyrite exists in the form of a monomer, a small part is associated with pyrite or is wrapped by pyrite, and a small part is wrapped by gangue. During the roasting process, the arsenic originally existing in the pyrite crystals is converted into ferric arsenate and is wrapped by the generated iron oxide. Part of the arsenic in arsenopyrite is converted into arsenic trioxide, and part of it is converted into ferric arsenate and is wrapped by iron oxide and gangue. The wrapped arsenic is difficult to remove, which seriously affects the quality of the subsequent iron concentrate.

[0008] (3) Poor adaptability, poor processing effect on fine particles and encapsulated ores, seriously affecting the recovery of valuable metals.

[0009] Based on the above problems, the present invention proposes a comprehensive recovery method for valuable components in arsenic-gold pyrite to overcome the current shortcomings and problems, improve the recovery rate of valuable components in difficult-to-treat minerals, achieve comprehensive utilization of resources, and enhance the economic and social benefits of the enterprise. Summary of the invention

[0010] In view of the above problems, the present invention provides a comprehensive recovery method for valuable components of arsenic-gold pyrite.

[0011] The specific technical solution is: a comprehensive recovery method for valuable components of arsenic-gold pyrite, comprising the following steps: (1) Classification of materials to be processed: The materials to be processed are transported to the airflow classifier for classification 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-particle materials. (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 the two particle size materials, roasting slag and sulfur dioxide fume (for making sulfuric acid) are obtained; Since microwaves have the characteristics of directly heating evenly and selectively heating inside an object, sintering is less likely to occur when using a microwave oven for baking. During the heating process, sulfur and arsenic with larger dielectric constants of the material will volatilize and burn first, causing a large number of cavities and cracks in the mineral particles. Moreover, 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, creating favorable conditions for subsequent dissociation. (3) high temperature oxidation rinsing of calcined slag: the calcined slag at a temperature of 300 to 400° C. obtained in step (2) is transported to a rinsing system for rinsing, and then filtered to obtain rinsed slag and rinsing liquid; The rinsing process is to add clear liquid to the high-temperature roasted slag (300-400℃), so that the roasted slag is suddenly cooled to produce greater tissue stress, breaking into fine particles, thereby opening the package, allowing the sulfide minerals to fully dissociate and expose the encapsulated gold particles; (4) Recovering copper from rinsing liquid: The rinsing liquid obtained in step (3) is transported to a stirring barrel, a copper precipitant is added, and the slurry is stirred for 30 minutes and then filtered to obtain a copper product and waste liquid, and the waste liquid is transported 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 by adding sodium hydroxide and sodium sulfide 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; This step utilizes the synergistic effect of sodium hydroxide and sodium sulfide to leach most of the arsenic in the rinsing slag (iron oxide) and improve the quality of the iron concentrate; (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.

[0012] 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.

[0013] 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.

[0014] 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.

[0015] Furthermore, the copper precipitant in step (4) is sodium hydrosulfide, sodium sulfide or thioacetamide.

[0016] Furthermore, the copper precipitant is added in an amount of 1.1 to 1.2 times the theoretical calculated amount.

[0017] Furthermore, during the alkaline leaching pretreatment in step (5), 15 to 20 kg / t of sodium hydroxide and 1 to 2 kg / t of sodium sulfide are added, the liquid-to-solid ratio is 1.5:1, the reaction temperature is 70° C., and the leaching time is 2 to 3 h.

[0018] Furthermore, in step (6), when gold and silver are extracted by carbon leaching, the liquid-to-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 15-30 g / L, and the leaching time is 32 h.

[0019] Beneficial effects of the present invention: In terms of specific process methods, the present invention divides the materials into products of different particle sizes according to the difference in the ignition point of pyrite with different particle sizes, and matches the corresponding microwave roasting conditions. While avoiding the sintering of fine-grained materials, the sulfur and arsenic with larger dielectric constants of the materials can be burned and volatilized first, so that a large number of cavities and cracks are formed, which is conducive to the crushing and dissociation during rinsing, and fully exposes the wrapped gold particles, thereby improving the recovery rate of gold. In addition, during rinsing, manganese dioxide is used to convert the residual iron sulfide and silver sulfide into oxides, and divalent iron is converted into trivalent iron precipitation, which creates favorable conditions for the subsequent separation of valuable components; during the alkaline leaching pretreatment of the rinsing slag, the synergistic effect of sodium hydroxide and sodium sulfide is cleverly used to leach most of the arsenic in the rinsing slag (iron oxide), which promotes the improvement of the quality of the iron concentrate.

[0020] It can be seen from the examples that the present invention can efficiently realize the comprehensive utilization of valuable components of arsenic-gold pyrite, with the recovery rates of gold, silver and sulfur reaching over 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. The present invention 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

[0021] Figure 1 is a flow chart of the method of the present invention; DETAILED DESCRIPTION

[0022] 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 in conjunction with 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 used to limit the present invention. Example 1

[0023] 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 in the form of encapsulated gold, accounting for 56.6%, of which metal sulfide encapsulation accounts for 51.95% and gangue encapsulation accounts for 4.65%; silver is mainly in the form of encapsulated silver, accounting for 79.80%; iron is mainly in the form of pyrite and pyrrhotite, accounting for 85.55%, followed by hematite and magnetite; copper is in the form of chalcopyrite; arsenic is mainly present in pyrite and arsenopyrite; the gangue minerals are mainly quartz and feldspar.

[0024] like Figure 1 As shown, the present invention is implemented on the arsenic-containing gold pyrite, and the specific steps are as follows: (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 -0.074 mm to +0.025 mm and -0.025 mm; (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 the two particle size materials, roasting slag and sulfur dioxide fume (for making sulfuric acid) are obtained; (3) High-temperature oxidation rinsing of calcined slag: The calcined 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; during rinsing, the liquid-to-solid ratio is 2.5:1, and the slurry mixing time is 30 minutes; during rinsing, 1 kg / t of manganese dioxide is added to convert the residual iron sulfide and silver sulfide into oxides using manganese dioxide, and to convert divalent iron into trivalent iron precipitate; after the manganese dioxide reacts, sodium hydroxide is added to adjust the pH value of the rinsing liquid to 3 to 5.4.

[0025] (4) Recovering copper from the rinsing liquid: The rinsing liquid obtained in step (3) is transported to a stirring barrel, and a copper precipitant (sodium hydrosulfide is used, and the amount added is 1.2 times the theoretical calculated amount) is added. After stirring and slurrying for 30 minutes, the precipitant is filtered to obtain a copper product and waste liquid, and the waste liquid is 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 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; (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-to-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 30 g / L, and the leaching time is 32 h to obtain gold-loaded activated carbon and high-quality iron ore concentrate.

[0026] The arsenic-gold pyrite of the present invention was implemented, and the test results obtained were: 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, the grade reached 64.23%, the arsenic content was reduced to 0.018%, and the iron recovery rate reached 96.12%. Example 2

[0027] 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 in the form of encapsulated gold, accounting for 57.5%, of which metal sulfide encapsulation accounts for 52.05% and gangue encapsulation accounts for 5.45%; silver is mainly in the form of encapsulated silver, accounting for 79.76%; iron is mainly in the form of pyrite and pyrrhotite, accounting for 86.15%, followed by hematite and magnetite; copper is in the form of chalcopyrite; arsenic is mainly present in pyrite and arsenopyrite; the gangue minerals are mainly quartz and feldspar.

[0028] like Figure 1 As shown, the present invention is implemented on the arsenic-containing gold pyrite, and the specific steps are as follows: (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 -0.074 mm to +0.025 mm and -0.025 mm; (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 for 2 h, and the roasting temperature of the -0.025 mm particle size material is 450 to 500°C for 2 h. After roasting, roasting slag and sulfur dioxide fume (for making sulfuric acid) are obtained for both particle size materials. (3) High-temperature oxidation rinsing of calcined slag: The calcined 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; during rinsing, the liquid-to-solid ratio is 2.5:1, and the slurry mixing time is 20 minutes; during rinsing, 0.8 kg / t of manganese dioxide is added to convert the residual iron sulfide and silver sulfide into oxides and to convert divalent iron into trivalent iron precipitate; after the manganese dioxide reacts, sodium hydroxide is added to adjust the pH value of the rinsing liquid to 3 to 5.4.

[0029] (4) Recovering copper from rinsing liquid: The rinsing liquid obtained in step (3) is transported to a stirring barrel, and a copper precipitant (sodium sulfide is used, and the amount added is 1.1 times the theoretical calculated amount) is added. After stirring and slurrying for 30 minutes, the precipitant is filtered to obtain a copper product and waste liquid, and the waste liquid is sent to a waste liquid treatment system; (5) Alkali leaching pretreatment of rinsed slag: The rinsed slag 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 slag with extremely low arsenic content and arsenic-containing alkaline leaching solution, which 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. When the carbon-based leaching is used to extract gold and silver, the liquid-to-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.

[0030] The arsenic-gold pyrite of the present invention was implemented, and the test results obtained were: 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, the grade reached 64.34%, the arsenic content was reduced to 0.018%, and the iron recovery rate reached 96.51%. Example 3

[0031] Raw material 3#: an arsenic-gold pyrite, the valuable elements are mainly Au, Ag, Fe, Cu, S, and their grades are 2.31g / t, 26.24g / t, 40.75%, 0.13%, 45.57% respectively: the harmful element is mainly arsenic, and its grade is 0.22%; the gold in the pyrite mainly exists in the form of encapsulated gold, with a occupancy rate of 56.7%, of which metal sulfide encapsulation accounts for 51.87% and gangue encapsulation accounts for 4.93%; silver mainly exists in the form of encapsulated silver, with a occupancy rate of 79.66%; iron mainly exists in the form of pyrite and pyrrhotite, with a occupancy rate of 85.65%, followed by hematite and magnetite; copper exists in the form of chalcopyrite; arsenic is mainly present in pyrite and arsenopyrite; the gangue minerals are mainly quartz and feldspar.

[0032] like Figure 1 As shown, the present invention is implemented on the arsenic-containing gold pyrite, and the specific steps are as follows: (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 -0.074 mm to +0.025 mm and -0.025 mm; (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 the two particle size materials, roasting slag and sulfur dioxide fume (for making sulfuric acid) are obtained; (3) High-temperature oxidation rinsing of calcined slag: The calcined 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; during rinsing, the liquid-to-solid ratio is 2.5:1, and the slurry mixing time is 25 minutes; during rinsing, 1 kg / t of manganese dioxide is added to convert the residual iron sulfide and silver sulfide into oxides and to convert divalent iron into trivalent iron precipitate; after the manganese dioxide reacts, sodium hydroxide is added to adjust the pH value of the rinsing liquid to 3 to 5.4.

[0033] (4) Recovering copper from the rinsing liquid: The rinsing liquid obtained in step (3) is transported to a stirring barrel, and a copper precipitant (sodium hydrosulfide is used, and the amount added is 1.1 times the theoretical calculated amount) is added. After stirring and slurrying for 30 minutes, the copper product and waste liquid are obtained by filtering, and the waste liquid is 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 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; (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 the carbon-based leaching is used to extract gold and silver, the liquid-to-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.

[0034] The arsenic-gold pyrite of the present invention was implemented, and the test results obtained were: 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, the grade reached 64.23%, the arsenic content was reduced to 0.019%, and the iron recovery rate reached 96.48%. Example 4

[0035] Raw material 4#: an arsenic-gold pyrite, the valuable elements are mainly Au, Ag, Fe, Cu, S, and their grades are 2.33g / t, 25.97g / t, 41.05%, 0.11%, 45.47% respectively; the harmful element is mainly arsenic, and its grade is 0.22%; the gold in the pyrite mainly exists in the form of encapsulated gold, with a occupancy rate of 57.1%, of which metal sulfide encapsulation accounts for 51.65% and gangue encapsulation accounts for 5.45%; silver mainly exists in the form of encapsulated silver, with a occupancy rate of 79.78%; iron mainly exists in the form of pyrite and pyrrhotite, with a occupancy rate of 86.25%, followed by hematite and magnetite; copper exists in the form of chalcopyrite; arsenic is mainly present in pyrite and arsenopyrite; gangue minerals are mainly quartz and feldspar.

[0036] like Figure 1 As shown, the present invention is implemented on the arsenic-containing gold pyrite, and the specific steps are as follows: (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 -0.074 mm to +0.025 mm and -0.025 mm; (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 the two particle size materials, roasting slag and sulfur dioxide fume (for making sulfuric acid) are obtained; (3) High-temperature oxidation rinsing of calcined slag: The calcined 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; during rinsing, the liquid-to-solid ratio is 2.5:1, and the slurry mixing time is 25 minutes; during rinsing, 0.8 kg / t of manganese dioxide is added to convert the residual iron sulfide and silver sulfide into oxides using manganese dioxide, and to convert divalent iron into trivalent iron precipitate; after the manganese dioxide reacts, sodium hydroxide is added to adjust the pH value of the rinsing liquid to 3 to 5.4.

[0037] (4) Recovering copper from the rinsing liquid: The rinsing 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 calculated amount) is added. After stirring and slurrying for 30 minutes, the copper product and waste liquid are obtained by filtering, and the waste liquid is 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 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; (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 the carbon-based leaching is used to extract gold and silver, the liquid-to-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.

[0038] The arsenic-gold pyrite of the present invention was implemented, and the test results obtained were: 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, the grade reached 64.35%, the arsenic content was reduced to 0.018%, and the iron recovery rate reached 96.46%.

[0039] In summary, the method was used to treat this type of encapsulated arsenic-containing gold pyrite, with a gold recovery rate of 92%, a silver recovery rate of 90%, a sulfur recovery rate of 99%, and a copper recovery rate 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%. It can be seen that the process method has strong applicability and stable production indicators for recycling and treatment, can achieve efficient and comprehensive utilization of arsenic-containing gold pyrite, and can also be used for the comprehensive recycling and treatment of arsenic-containing encapsulated sulfur concentrate, iron concentrate, gold concentrate and other ores, and has important industrial promotion and application value.

[0040] 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, and any modifications, equivalent substitutions, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A comprehensive method for recovering valuable components from arsenic-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 -0.074 mm to +0.025 mm and -0.025 mm; (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 fume are obtained for both particle size materials; (3) high temperature oxidation rinsing of calcined slag: the calcined slag at a temperature of 300 to 400° C. obtained in step (2) is transported to a rinsing system for rinsing, and then filtered to obtain rinsed slag and rinsing liquid; (4) Recovering copper from rinsing liquid: The rinsing liquid obtained in step (3) is transported to a stirring barrel, a copper precipitant is added, and the slurry is stirred for 30 minutes and then filtered to obtain a copper product and waste liquid, and the waste liquid is transported 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 by adding sodium hydroxide and sodium sulfide 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 of arsenic-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 of arsenic-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 precipitate.

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

6. A comprehensive recovery method of valuable components of arsenic-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 calculated amount.

7. The method for comprehensive recovery of valuable components of arsenic-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-to-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 of arsenic-gold pyrite according to claim 1, characterized in that: In step (6), when gold and silver are extracted by carbon leaching, the liquid-to-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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