Gold extraction method from gold-containing iron matte by short cycle smelting and leaching

Abstract

The present application belongs to the field of precious metal metallurgy and resource comprehensive utilization, and particularly relates to a gold extraction method with a short process of gold-containing iron matte circulation smelting and leaching, which comprises the following steps: mixing complex gold concentrate and cyanide tailings to obtain gold-containing iron matte through controlled oxygen sulfidation smelting; reducing smelting and leaching the gold-containing iron matte with a smelting agent and pulverized coal to obtain lead-bismuth precious alloy and poor gold-containing iron matte, and generate high-temperature flue gas at the same time; oxidizing refining the lead-bismuth precious alloy to obtain crude gold product, smelting agent regeneration material and copper bismuth slag; preparing iron concentrate powder by removing lead and bismuth from the poor gold-containing iron matte; collecting the high-temperature flue gas from the smelting furnace and the lead-bismuth removal smelting furnace, and returning the smelting agent regeneration material generated by the refining furnace to the smelting furnace for reduction. The method uses molten pool smelting technology to process multi-metal complex gold concentrate, captures gold with endogenous iron and sulfur, and circulates smelting and leaching of gold with lead and bismuth, so that iron and sulfur are used in a high-value way, the gold extraction rate is high, the production cycle is short, the raw material adaptability is strong, and it is a clean and efficient pyrometallurgical "non-cyanide" gold extraction process.

Description

Technical Field

[0001] This application belongs to the field of non-ferrous metal metallurgy technology, specifically relating to a short-process gold extraction method using gold-bearing iron matte through cyclic smelting. Background Technology

[0002] Gold, as a scarce strategic metal, is widely used in gold jewelry, currency reserves, and high-tech industries. Currently, cyanidation is the mainstream gold extraction process, but processing one ton of ore generates approximately one ton of cyanide tailings, which are classified as hazardous solid waste. This is accompanied by a large amount of difficult-to-treat cyanide-containing wastewater, leading to high environmental disposal costs. As complex gold mines gradually become the main source of gold extraction, the cyanidation process faces the problem of high gold content in the tailings, typically ranging from 1-10 g / t. This results in a serious loss of precious metal resources, and associated valuable metals in the ore are largely unrecoverable, creating an industry predicament characterized by difficult disposal, low recovery rates, and poor resource utilization.

[0003] To overcome these bottlenecks, the industry has explored various alternative approaches. Among them, cyanide-free hydrometallurgical processes using thiosulfates, thiourea, and halogens as leaching agents avoid the environmental risks of cyanide, but their practical application is still limited by high reagent costs, poor system stability, and low leaching rates for complex minerals, and they have not fundamentally broken through the original process bottlenecks. On the other hand, pyrometallurgical processes, represented by copper-lead smelting, can achieve efficient gold and silver capture, and technologies for co-smelting with gold concentrate have been developed. For example, patent application CN117385185A proposes a method for co-smelting gold- and antimony-containing resources with copper concentrate and lead materials, utilizing copper matte to capture gold and lead to capture antimony, achieving simultaneous recovery of gold and antimony. However, this technology is centered on bulk metal smelting, with gold only recovered as a byproduct, and requires large-scale external purchases of copper and lead concentrates as gold-capturing ingredients. It suffers from high construction investment and the process's economics being closely tied to bulk metal market prices, making it unsuitable for production enterprises whose main product is gold.

[0004] Complex gold concentrates typically contain high levels of iron, sulfur, and various associated metals, and these iron and sulfur components are key elements in the formation of matte. Therefore, utilizing the abundant Fe and S endogenous components of the gold ore itself for direct sulfidation smelting, enriching valuable metals such as gold in the iron matte phase, represents a more efficient and innovative technological approach. However, iron matte's ability to capture gold and silver, as well as its high-temperature sedimentation and separation capabilities, are inferior to those of copper and lead. Furthermore, the industry has not yet developed an efficient and clean standardized treatment plan for the key intermediate product generated by this process—"gold-bearing iron matte." Given the high iron and sulfur content of complex gold concentrates, there is an urgent need to develop a new, short-process technology that integrates iron matte gold capture and extraction, based on endogenous component regulation. Summary of the Invention

[0005] The present invention aims to solve the problems in the prior art and provide a short-process gold extraction method for gold-bearing iron matte through cyclic melting.

[0006] To achieve the above objectives, this application provides a short-process gold extraction method using gold-bearing iron matte through cyclic smelting, comprising the following steps:

[0007] (1) Complex gold concentrate is combined with cyanide tailings and additives are added. After mixing, it is smelted by controlled oxygen sulfidation to obtain gold-containing iron matte. (2) The gold-containing iron matte described in step (1) is added to the smelting furnace for reduction smelting. Oxygen and natural gas are introduced, pulverized coal is injected and smelting agent is added to obtain precipitated lead-bismuth noble alloy and gold-poor iron matte, while producing high-temperature flue gas. The high-temperature flue gas is purified by bag filter dust removal and then enters the ion liquid absorption tower to recover SO2. The bag filter dust is returned to be used as smelting agent replenishment material. (3) The lead-bismuth precious alloy described in step (2) is oxidized and refined to separate and extract crude gold. Oxygen-rich air is introduced during the oxidative refining process to produce by-products: recycled flux and copper-bismuth slag. (4) The lead and bismuth in the gold-poor iron matte described in step (2) are removed by fumigation. The remaining iron-containing components are prepared by boiling roasting to produce iron concentrate. The sulfur-containing flue gas produced is sent to prepare industrial sulfuric acid.

[0008] In the above-mentioned short-process extraction method, preferably, in step (1), the gold-containing iron matte contains: Fe 40-70wt%, S 25-35wt%, Au 20-250 g / t, and Ag 20-500 g / t.

[0009] In the above-mentioned short-process extraction method, preferably, in step (2), the gold-containing iron matte melt enters the smelting furnace through a closed chute, and is heated by a mixture of oxygen and natural gas with an oxygen-fuel ratio of 2:1. Pulverized coal and smelting agent are mixed and added into the furnace to maintain a reducing atmosphere. The reduction smelting temperature is 1200-1350 ℃, and the time is 2 h. The smelting furnace is preferably a bottom-blown furnace. The amount of pulverized coal added in the reduction smelting process accounts for 2-12% of the mass of gold-containing iron matte; the smelting agent includes one or more of metallic lead and metallic bismuth, lead-bismuth alloy, oxides, sulfides and sulfates, and waste lead paste, preferably a mixture of PbO and Bi2O3; the amount of smelting agent added accounts for 10-30% of the mass of gold-containing iron matte, the lead and bismuth components are reduced to elemental form, gold is captured from the iron matte, and lead-bismuth noble alloy and gold-poor iron matte are separated.

[0010] In this invention, optimizing the amount of extractant added is a key control method to achieve efficient enrichment of precious metals. If too much extractant is added, the alloy melt generated by reduction will quickly aggregate into large particles and accelerate sedimentation, resulting in insufficient contact time with gold and inadequate capture. Appropriate addition of extractant can not only effectively prevent the precious metals from being over-diluted, but also achieve efficient concentration and deep enrichment of gold.

[0011] In the above-mentioned short-process extraction method, preferably, in step (2), the gold content in the lead-bismuth noble alloy is 100-600 g / t, the silver content is 50-1200 g / t, and the gold remaining in the gold-poor iron matte is less than 0.5 g / t.

[0012] In step (2) of this invention, if iron matte with a gold content greater than 0.5 g / t is produced after reduction smelting, it is mixed with the next batch of gold-containing iron matte melt and then smelted and enriched with gold again.

[0013] In the above-mentioned short-process extraction method, preferably, in step (2), the lead and bismuth contained in the high-temperature flue gas are recovered after being purified by bag filter dust removal and can be returned for reduction smelting.

[0014] In step (2) of this invention, the main reactions that occur are as follows: 2PbO + C = 2Pb + CO2(g) 3PbO + FeS = 3Pb + FeO + SO2(g) PbO + FeS = PbS + FeO PbO + Fe = Pb + FeO 2Bi₂O₃ + 3C = 4Bi + 3CO₂(g) Bi2O3+ FeS = 2Bi + FeO + SO2(g) Bi₂O₃ + 3FeS = Bi₂S₃ + ​​3FeO Bi₂O₃ + 3Fe = 3FeO + 2Bi 2FeO + C = 2Fe + CO2(g) [Au] 铁锍相 → (Au) Pb-Bi合金相 [Ag] 铁锍相 → (Ag) Pb-Bi合金相 During the reduction smelting stage, a process similar to liquid-liquid extraction occurs, where the lead and bismuth components in the extractant are first reduced to their elemental form. Because precious metals such as gold and silver have a much stronger affinity for lead and bismuth at the thermodynamic and chemical bonding levels than for iron matte, gold has a higher solubility in lead and bismuth at high temperatures. During the reduction smelting process, precious metals migrate from the iron matte phase to the lead-bismuth liquid phase, forming more stable solid solutions or intermetallic compounds. As the precious metals accumulate in the lead-bismuth droplets, they gradually aggregate and settle, ultimately forming a gold- and silver-rich precious metal alloy, thus achieving highly efficient and selective capture and separation of precious metals from iron matte.

[0015] In the above-mentioned short-process extraction method, preferably, in step (3), the recycled material of the molten agent is mainly lead-bismuth oxide slag, which can be returned to the batching in step (2); the copper-bismuth slag is generated by the system's cycle accumulation, and after copper is recovered, the bismuth slag can be returned to the molten agent along with the recycled material of the molten agent.

[0016] In the above-mentioned short-process extraction method, preferably, in step (4), after the lead and bismuth are removed by fumigation and volatilization of the gold-poor iron matte, qualified pyrite concentrate is produced, which is sent to fluidized bed roasting to prepare iron concentrate powder. The generated smoke dust is lead-bismuth material, which is returned to reduction smelting and used in conjunction with the smelting agent.

[0017] In the preferred embodiment of the above-mentioned short-process extraction method, in step (4), the fuming temperature is 1200-1250℃, pulverized coal is injected and oxygen-enriched air is introduced, and the air-to-coal ratio is 3-5 m. 3 / kg, reaction time is 1-2.5 h.

[0018] Compared with the prior art, this application has the following beneficial effects: (1) The sources of the extractant are diverse and flexible, and it is easy to reduce and recycle. It can be obtained from the by-products accumulated in the system production cycle and the dismantling materials of waste lead-acid batteries, or it can be supplemented by external purchases. The lead and bismuth materials in the recycled extractant and the flue dust can be returned to the reduction and extraction stage after processing, and can be used in conjunction with the extractant to achieve recycling. This not only ensures the stability of the raw material supply, but also reduces the dependence on externally purchased resources. At the same time, it can recover the associated valuable metals such as copper, lead, antimony and bismuth in the raw materials.

[0019] (2) Iron matte can be used in a high-value manner. Iron matte with a gold content greater than 0.5 g / t produced in the reduction smelting stage can be mixed with the next batch of gold-containing iron matte and smelted again to recover residual gold and associated valuable metals, and reduce the loss of gold in the final slag. Iron in the gold-poor iron matte can be used to prepare iron concentrate, and sulfur can be converted into SO2 or prepared into industrial sulfuric acid, realizing the high-value recovery of iron and sulfur resources and improving the comprehensive utilization rate and process economy of complex gold resources.

[0020] (3) The material is processed to achieve step-by-step reduction, from complex gold-bearing resources (complex gold concentrate, cyanide tailings) to gold-rich systems (gold-containing iron matte, lead-bismuth precious alloys), the material quality decreases step by step; in the oxygen-controlled sulfidation smelting stage, the slag-forming components in the raw materials are smelted into general solid waste, and the endogenous iron and sulfur components of the gold resources are used to achieve the initial enrichment of precious metals. In the reduction smelting stage, iron matte and lead-bismuth precious alloys are further separated, so that gold is concentrated twice and the gold recovery efficiency is significantly improved.

[0021] (4) This invention uses molten pool smelting technology to process complex polymetallic gold concentrates. It uses endogenous iron and sulfur to capture gold to form gold-bearing iron matte. Under a reducing atmosphere, the precious metal is "extracted" from the stable iron matte system to the more easily processed lead-bismuth precious alloy phase using lead-bismuth melt. At the same time, with the "extractant" recycling system, lead-bismuth recycling gold extraction is realized. This not only greatly shortens the entire process and makes the raw materials more adaptable, but also significantly improves the gold extraction rate. It is a clean and efficient pyrometallurgical "cyanide-free" gold extraction process. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a process flow diagram of the gold extraction method for gold-containing iron matte using a short-process recycling process according to the present invention. Detailed Implementation

[0024] To facilitate understanding of this application, the following description will be more comprehensive and detailed in conjunction with the accompanying drawings and preferred embodiments, but the scope of protection of this application is not limited to the following specific embodiments.

[0025] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of this application.

[0026] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0027] Example 1: A short-process gold extraction method using gold-bearing iron matte with cyclic smelting, the process flow of which is as follows: Figure 1 As shown, it includes the following steps: (1) Complex gold concentrate, cyanide tailings and additives are mixed and added to a smelting furnace for controlled oxygen sulfidation smelting to produce gold-bearing iron matte, high-temperature flue gas and smelting slag. The gold-bearing iron matte includes Fe 54.86wt%, S 27.31wt%, Au 128.8 g / t and Ag 271.4 g / t.

[0028] (2) The gold-bearing iron matte melt is fed into a bottom-blown furnace through a chute. Oxygen and natural gas with an oxygen-fuel ratio of 2:1 are introduced. 25% of the mass of the gold-bearing iron matte is added as a flux and 10% as pulverized coal for reduction. The flux mainly consists of PbO and Bi2O3, with m(PbO) / m(Bi2O3) = 1. The smelting temperature is 1250 ℃, and the smelting time is 2 h. After smelting, lead-bismuth noble alloy and gold-poor iron matte are separated. The lead-bismuth noble alloy contains 563.32 g / t Au, 1180.03 g / t Ag, 1.25% Fe, and 0.82% S; the gold-poor iron matte contains 0.27 g / t Au, 2.37 g / t Ag, 56.92% Fe, and 27.65% S.

[0029] (3) The lead-bismuth precious alloy obtained in step (2) is oxidized, refined, and cast to obtain crude gold. The by-product of oxidation refining, the recycled flux, is mainly lead-bismuth oxide slag, which can be returned to the batching in step (2). The lead and bismuth contained in the high-temperature flue gas are recovered after being purified by bag filter dust removal and returned for reduction smelting. The bismuth slag remaining after copper recovery of copper-bismuth slag can be returned to step (2) for recycling. The lead and bismuth in the lean gold iron matte obtained in step (2) are removed, and the remaining iron-containing components are prepared by fluidized bed roasting. The fuming temperature is 1250 ℃, pulverized coal is injected and oxygen-enriched air is introduced, and the air-coal ratio is 4 m. 3 / kg, the reaction time is 2 h, the lead and bismuth material in the fuming and volatilizing dust is returned to step (2) and used in conjunction with the extractant, and the sulfur-containing flue gas produced is sent to prepare industrial sulfuric acid.

[0030] Calculations show that the gold capture rate in the step of reducing and extracting gold-containing iron matte to obtain lead-bismuth noble alloy in this embodiment is 99.22%.

[0031] Example 2: A short-process gold extraction method using gold-bearing iron matte with cyclic smelting, the process flow of which is as follows: Figure 1 As shown, it includes the following steps: (1) The same gold-bearing iron matte as in Example 1 was used as raw material. The gold-bearing iron matte melt was fed into the smelting furnace through a chute. Oxygen and natural gas with an oxygen-fuel ratio of 2:1 were introduced. 30% of the mass of the gold-bearing iron matte was added to the furnace as a flux and 8% of the mass of pulverized coal for reduction. The main components of the flux were PbO and Bi2O3, and m(PbO) / m(Bi2O3) = 1.2. The smelting temperature was 1250 °C and the time was 2 h. After smelting, lead-bismuth noble alloy and gold-poor iron matte were separated. Among them, the lead-bismuth noble alloy contained Au 558.76 g / t, Ag 1132.17 g / t, Fe 1.83%, and S 0.75%; the gold-poor iron matte contained Au 0.40 g / t, Ag 3.29 g / t, Fe 55.96%, and S 28.8%.

[0032] (2) The subsequent steps are consistent with those in Example 1.

[0033] Calculations show that the gold capture rate in the step of reducing and extracting gold-containing iron matte to obtain lead-bismuth noble alloy in this embodiment is 98.89%.

[0034] Example 3: A short-process gold extraction method using gold-bearing iron matte with cyclic smelting, the process flow of which is as follows: Figure 1 As shown, it includes the following steps: (1) The same gold-bearing iron matte as in Example 1 was used. The gold-bearing iron matte melt was fed into the smelting furnace through a chute. Oxygen and natural gas with an oxygen-fuel ratio of 2:1 were introduced. 20% of the mass of the gold-bearing iron matte was added to the furnace as a flux and 12% of pulverized coal for reduction. The main components of the flux were PbO and Bi2O3, with m(PbO) / m(Bi2O3) = 0.8. The smelting temperature was 1250 °C and the time was 2 h. After smelting, lead-bismuth noble alloy and gold-poor iron matte were separated. Among them, the lead-bismuth noble alloy contained Au 554.21 g / t, Ag 1175.54 g / t, Fe 1.51%, and S 0.84%; the gold-poor iron matte contained Au 0.31 g / t, Ag 2.78 g / t, Fe 57.67%, and S 28.9%.

[0035] (2) The subsequent steps are consistent with those in Example 1.

[0036] Calculations show that the gold capture rate in the step of reducing and extracting gold-containing iron matte to obtain lead-bismuth noble alloy in this embodiment is 99.17%.

[0037] Comparative Example 1: The extraction process of this comparative example includes the following steps: (1) Same as step (1) in Example 1.

[0038] (2) The gold-containing iron matte melt is fed into the smelting furnace through a chute. Oxygen and natural gas with an oxygen-fuel ratio of 2:1 are introduced. 25% of the mass of the gold-containing iron matte is added as a flux and 10% as pulverized coal for reduction. The flux mainly consists of PbO and Bi2O3, with m(PbO) / m(Bi2O3) = 1. The smelting temperature is 1150 ℃, and the time is 2 h. After smelting, lead-bismuth noble alloy and gold-poor iron matte are separated. The lead-bismuth noble alloy contains 534.6 g / t Au, 1037.2 g / t Ag, 2.48% Fe, and 1.33% S; the gold-poor iron matte contains 15.16 g / t Au, 25.81 g / t Ag, 56.26% Fe, and 27.67% S.

[0039] (3) is the same as step (3) in Example 1.

[0040] Calculations show that the gold capture rate using this comparative scheme is 87.06%.

[0041] Comparative Example 2: The extraction process of this comparative example includes the following steps: (1) Same as step (1) in Example 1.

[0042] (2) The gold-containing iron matte melt is fed into the smelting furnace through a chute. Oxygen and natural gas with an oxygen-fuel ratio of 2:1 are introduced. 12% by weight of the gold-containing iron matte flux and 10% by weight of pulverized coal are added to the furnace for reduction. The flux mainly consists of PbO and Bi2O3, with m(PbO) / m(Bi2O3) = 1. The smelting temperature is 1250 ℃, and the time is 2 h. After smelting, lead-bismuth noble alloy and gold-poor iron matte are separated. The lead-bismuth noble alloy contains 536.09 g / t Au, 1083.11 g / t Ag, 1.99% Fe, and 0.86% S; the gold-poor iron matte contains 10.95 g / t Au, 23.87 g / t Ag, 55.23% Fe, and 27.13% S.

[0043] (3) is the same as step (3) in Example 1.

[0044] Calculations show that the gold capture rate using this comparative scheme is 90.29%.

[0045] Comparative Example 3: The extraction process of this comparative example includes the following steps: (1) Same as step (1) in Example 1.

[0046] (2) The gold-containing iron matte melt is fed into the smelting furnace through a chute. Oxygen and natural gas with an oxygen-fuel ratio of 2:1 are introduced. 25% of the mass of the gold-containing iron matte is added as a flux and 4% of pulverized coal for reduction. The flux mainly consists of PbO and Bi2O3, with m(PbO) / m(Bi2O3) = 1. The smelting temperature is 1250 ℃, and the time is 2 h. After smelting, lead-bismuth noble alloy and gold-poor iron matte are separated. The lead-bismuth noble alloy contains 538.78 g / t Au, 1062.43 g / t Ag, 2.61% Fe, and 1.32% S; the gold-poor iron matte contains 12.87 g / t Au, 28.74 g / t Ag, 58.23% Fe, and 28.52% S.

[0047] (3) is the same as step (3) in Example 1.

[0048] Calculations show that the gold capture rate using this comparative scheme is 88.37%.

[0049] Comparative Example 4: The extraction process of this comparative example includes the following steps: (1) Same as step (1) in Example 1.

[0050] (2) The gold-containing iron matte melt is fed into the smelting furnace through a chute. Oxygen and natural gas with an oxygen-fuel ratio of 2:1 are introduced. 25% of the mass of the gold-containing iron matte is added as a flux and 10% as pulverized coal for reduction. The flux mainly consists of PbO and PbSO4, with m(PbO) / m(PbSO4) = 1.2. The smelting temperature is 1250 ℃, and the smelting time is 2 h. After smelting, lead-bismuth noble alloy and gold-poor iron matte are separated. The lead-bismuth noble alloy contains 543.98 g / t Au, 1071.09 g / t Ag, 1.81% Fe, and 0.77% S; the gold-poor iron matte contains 11.73 g / t Au, 35.21 g / t Ag, 57.55% Fe, and 28.94% S.

[0051] (3) is the same as step (3) in Example 1.

[0052] Calculations show that the gold capture rate using this comparative scheme is 85.74%.

[0053] Comparative Example 5: The extraction process of this comparative example includes the following steps: (1) Same as step (1) in Example 1.

[0054] (2) The gold-bearing iron matte melt was fed into the smelting furnace through a chute. Oxygen and natural gas with an oxygen-fuel ratio of 2:1 were introduced. 25% PbO and 10% pulverized coal by mass of the gold-bearing iron matte were added to the furnace for reduction. The smelting temperature was 1250 ℃ and the time was 2 h. After smelting, lead-bismuth noble alloy and gold-poor iron matte were separated. The lead-bismuth noble alloy contained Au 539.13 g / t, Ag 1069.44 g / t, Fe 1.95%, and S 1.03%; the gold-poor iron matte contained Au 14.84 g / t, Ag 21.08 g / t, Fe 55.87%, and S 26.72%.

[0055] (3) is the same as step (3) in Example 1.

[0056] Calculations show that the gold capture rate using this comparative scheme is 89.56%.

[0057] Results analysis: The results of Examples 1-3 and Comparative Examples 1-5 show that the gold extraction rate is high under the synergistic treatment of various factors in this application. This indicates that adding appropriate components of the extractant and the amount of pulverized coal, and setting a suitable reduction extraction temperature, can effectively capture gold in iron matte and separate lead-bismuth noble alloy.

[0058] The above are merely preferred embodiments of this application. It should be noted that this application is not limited to the above embodiments. For those skilled in the art, several improvements and modifications can be made without departing from the principles of this application. Any modifications, equivalent substitutions, improvements, etc., made within the methods and principles of this application should also be considered within the scope of protection of this application.

Claims

1. A short-process gold extraction method using gold-bearing iron matte through cyclic smelting, characterized in that, Includes the following steps: (1) Complex gold concentrate is combined with cyanide tailings and additives are added. After mixing, it is smelted by controlled oxygen sulfidation to obtain gold-containing iron matte. (2) The gold-containing iron matte described in step (1) is added to the smelting furnace for reduction smelting. Oxygen and natural gas are introduced, pulverized coal is injected and smelting agent is added to obtain precipitated lead-bismuth noble alloy and gold-poor iron matte, while producing high-temperature flue gas. The high-temperature flue gas is purified by bag filter dust removal and then enters the ion liquid absorption tower to recover SO2. The bag filter dust is returned to be used as smelting agent replenishment material. (3) The lead-bismuth precious alloy described in step (2) is oxidized and refined to separate and extract crude gold. Oxygen-rich air is introduced during the oxidative refining process to produce by-products: recycled flux and copper-bismuth slag. (4) The lead and bismuth in the gold-poor iron matte described in step (2) are removed by fumigation. The remaining iron-containing components are prepared by boiling roasting to produce iron concentrate. The sulfur-containing flue gas produced is sent to prepare industrial sulfuric acid.

2. The gold extraction method for gold-bearing iron matte using a short-process recycling process according to claim 1, characterized in that, In step (1), the gold-containing iron matte contains 40-70wt% Fe, 25-35wt% S, 20-250 g / t Au and 20-500 g / t Ag.

3. The gold extraction method for gold-bearing iron matte using a short-process recycling process according to claim 1, characterized in that, In step (2), the gold-containing iron matte melt enters the smelting furnace through a closed chute, and is heated by a mixture of oxygen and natural gas with an oxygen-fuel ratio of 2:

1. Pulverized coal and smelting agent are mixed and added into the furnace to maintain a reducing atmosphere. The reduction smelting temperature is 1200-1350 ℃ and the time is 2 h. The smelting furnace is preferably a bottom-blown furnace. The amount of pulverized coal added in the reduction smelting process accounts for 2-12% of the mass of gold-containing iron matte; the smelting agent includes one or more of the following: a mixture of metallic lead and metallic bismuth, lead-bismuth alloy, lead-bismuth oxide, lead-bismuth sulfide and lead-bismuth sulfate, and waste lead paste, preferably a mixture of PbO and Bi2O3; the amount of smelting agent added accounts for 10-30% of the mass of gold-containing iron matte, the lead and bismuth components are reduced to elemental form, gold is captured from the iron matte, and lead-bismuth noble alloy and gold-poor iron matte are separated.

4. The gold extraction method for gold-bearing iron matte using a short-process recycling process according to claim 1, characterized in that, In step (2), the gold content in the lead-bismuth noble alloy is 100-600 g / t, and the silver content is 50-1200 g / t; the gold content remaining in the gold-poor iron matte is less than 0.5 g / t; if iron matte with a gold content higher than 0.5 g / t is produced after reduction smelting, it is mixed with the next batch of gold-containing iron matte melt and refined again to enrich the gold.

5. The gold extraction method for gold-bearing iron matte using a short-process recycling process according to claim 1, characterized in that, In step (2), the lead and bismuth contained in the high-temperature flue gas are recovered after being purified by bag filter dust removal and returned for reduction smelting.

6. The gold extraction method for gold-bearing iron matte using a short-process recycling process according to claim 1, characterized in that, In step (3), the recycled flux is mainly lead-bismuth oxide slag, which can be returned to the batching in step (2); the copper-bismuth slag is generated by the system's cycle accumulation. After copper is recovered, the bismuth slag can be returned to the smelting process together with the recycled flux.

7. The gold extraction method for gold-bearing iron matte using a short-process recycling process according to claim 1, characterized in that, In step (4), after the lead and bismuth are removed by fumigation and volatilization of the gold-poor iron matte, qualified pyrite concentrate is produced, which is sent to fluidized bed roasting to prepare iron concentrate powder. The generated dust is lead-bismuth material, which is returned to reduction smelting and used in conjunction with the smelting agent.

8. The gold extraction method for gold-bearing iron matte using a short-process recycling process according to claim 1, characterized in that, In step (4), the fuming temperature is 1200-1250 ℃, pulverized coal is injected and oxygen-enriched air is introduced, and the air-to-coal ratio is 3-5 m. 3 / kg, reaction time is 1-2.5 h.

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