Method for recovering gold by adopting leaching process

Abstract

The invention relates to a method for recovering gold by adopting a leaching process, which is beneficial to full contact of a gold ore raw material with sodium cyanide through a crushing and screening process, and improves the recovery rate of the gold ore. The cyaniding gold-containing barren liquor generated after washing of a carbon extraction sieve in the process of leaching and recovering gold from the high-grade raw ore is used for replacing direct spraying of sodium cyanide on the secondary-grade raw ore, so that the consumption of the sodium cyanide is reduced, and the economic cost of recovering gold is reduced; meanwhile, the problem that the smelting cost of gold mud produced by leaching of the high-grade raw ore is increased due to the fact that cyanided gold-containing barren liquor which is continuously accumulated and enriched with impurity ions is directly recycled and used for leaching of the high-grade raw ore is avoided, and electrolysis barren liquor generated after electrolysis of the gold-containing barren liquor is treated through an intermediate product treatment process; according to the method, impurity ions enriched in the electrolytic barren liquor are removed, meanwhile, in the electrolytic barren liquor treatment process, tail gas and tail liquor generated in the high-grade raw ore leaching gold recovery process are neutralized, and the influence of the tail gas on the environment is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of mineral processing, and in particular relates to a method for recovering gold by adopting a leaching process. Background Art

[0002] At present, the cyanidation method is mainly used in my country's gold production. The cyanidation method is an economical and effective method for extracting gold and silver. In addition, according to the different gold content, it is divided into high-grade ore, sub-grade ore and low-grade ore. Among them, high-grade ore has a high gold content, so the cyanide leaching process is directly used to recover gold. Sub-grade ore has a relatively low gold content, so the cyanide leaching process consumes a large amount of cyanide to recover gold, and the amount of gold recovered is relatively small, which is low in economic efficiency. Therefore, heap leaching is usually used to recover gold. For low-grade ore, due to the extremely low gold content, even if the heap leaching process is used to recover gold, the amount of gold that can be recovered is still relatively economical compared to the amount of cyanide consumed. Therefore, for low-grade ore, it is usually used as sand and gravel raw materials for construction after pre-disposal. The cyanide method needs to use cyanide leaching to extract gold. The cyanide precious liquid produced after cyanide leaching and gold extraction has associated gold minerals, such as copper minerals, iron minerals, arsenic minerals, lead minerals, etc., and the impurity ions such as copper, zinc, iron, arsenic, silicate, etc. are constantly accumulated and enriched in the cyanide precious liquid, which not only has a certain impact on the leaching of gold and silver in the minerals, but also leads to frequent gold mud extraction from the cyanide precious liquid; and the grade of gold mud decreases, and the subsequent smelting and disposal costs of gold mud increase several times; at the same time, due to the high gold grade of the filtrate carried by the cyanide tailings, the loss of dissolved gold is caused;

[0003] However, in the process of recovering gold by heap leaching, due to the relatively low gold content in the sub-grade ore, the efficiency of cyanide extraction is reduced compared with the method of extracting gold by cyanide leaching by direct cyanide spraying, resulting in the cyanide not being fully utilized. In addition, due to the relatively low gold content in the sub-grade ore, the content of other base metals other than gold in the sub-grade ore is relatively higher, and the accumulation and enrichment of associated gold minerals is faster, so the cost of directly using cyanide spraying is higher.

[0004] Chinese patent application number 202211122752.6 discloses a method for purifying cyanide gold-containing precious liquid to improve the grade of gold mud replacement. The method takes the purification of cyanide gold-containing precious liquid and its recycling in the cyanide gold extraction production process as the starting point, and the cyanide gold-containing precious liquid is subjected to a first-level carbide slag calcification treatment, a second-level carbon dioxide decalcification treatment, a third-level iron salt + calcium sulfate preliminary purification treatment, a fourth-level ammonium salt deep purification treatment, and a fifth-level zinc powder replacement process. The technical method realizes the purification of cyanide gold-containing precious liquid, improves the grade of zinc powder replacement gold mud, increases the precious liquid processing capacity, and improves the index stability of the cyanide gold extraction system, so as to achieve the comprehensive recovery and recycling of cyanide gold extraction liquid. However, it will cause zinc accumulation in the cyanide gold extraction liquid. In the process of recovering gold, as the cyanide concentration is low, zinc hydroxide and zinc cyanide precipitation will form on the zinc surface, which hinders the replacement of gold.

[0005] In view of the shortcomings of existing technologies, improvements need to be made. Summary of the invention

[0006] In view of this, the object of the present invention is to provide a method for recovering gold using a leaching process to solve the above problems.

[0007] To achieve the above object, the technical solution adopted by the present invention is: a method for recovering gold by leaching process, which specifically includes crushing and screening process, high-grade ore leaching gold recovery process, sub-grade ore heap leaching gold recovery process, and intermediate product processing process;

[0008] Crushing and screening process

[0009] S1: The gold ore is crushed by the primary crusher and then crushed by the secondary crusher. The products after the initial crushing are screened by a single-layer circular vibrating screen. The products on the screen are fed to the secondary crusher by a belt conveyor for further crushing. The products under the screen are the ore that has been crushed.

[0010] S2: The ore after the crushing process in step S1 is fed into the ball mill, and the ore discharged from the ball mill enters the classifier. The sand returned by the classifier is returned to the ball mill for re-grinding, and the overflow of the classifier completes the grinding;

[0011] S3: The ore ground in step S2 is fed into a magnetic separator for magnetic separation and screening to select low-grade ore pulp, medium-grade ore pulp and high-grade ore pulp. The low-grade ore is used as a raw material for construction sand and gravel after pre-discharging tailings.

[0012] High-grade ore leaching and gold recovery process

[0013] S1: The high-grade raw ore pulp flows by gravity to the thickener for pre-leaching concentration. The bottom flow of the thickener is pumped to the mixing tank by a pump. Sodium cyanide is added to the mixer for pre-leaching to obtain cyanide gold-containing precious liquid and high-gold filter residue;

[0014] S2: Add activated carbon to the cyanide gold-containing precious liquid. The activated carbon moves forward against the slurry flow. After being washed by the carbon extraction screen, the activated carbon adsorbs the gold ore in the cyanide gold-containing precious liquid to obtain gold-loaded carbon. At the same time, the gold content in the cyanide gold-containing precious liquid is reduced to be used as the cyanide gold-containing lean liquid.

[0015] S3: After being washed with water, the gold-loaded carbon enters the desorption column for high-temperature and high-pressure cyanide-free desorption. The desorbent is a sodium hydroxide solution. During the desorption, the electrolytic cell is turned on for electrolysis, so that the gold in the filtrate is enriched in the electrolytic cell to form gold mud. The filtrate without gold becomes electrolytic lean liquid and returns to the analytical column to continue desorption and elution of the gold-loaded carbon.

[0016] S4: washing the gold mud to remove the tail liquid consisting of sodium cyanide, sodium hydroxide and a small amount of chloride ions remaining in the gold mud during the desorption electrolysis process;

[0017] S5: The washed gold mud is acid-soaked in dilute nitric acid, and the generated tail gas (the base metals in the gold mud react with nitric acid during the acid-soaking operation to generate nitrogen oxide gas. Due to the violent reaction, bubbles are generated, and the nitrogen oxides and the materials splashed by the bubble bursting together constitute the tail gas) is sprayed and absorbed by the flue, fan, and multi-stage absorption tower, and finally discharged through the tail gas chimney. The silver and other base metals in the gold mud react with nitric acid to generate soluble nitrates that enter the solution, while gold does not react with nitric acid and is deposited in a solid state at the bottom of the reaction vessel to form precipitated gold mud, and the base metal impurities are removed from the gold mud;

[0018] Nitric acid is added in stages, and before adding acid in each stage, the product of the previous stage reaction is washed 2-3 times with hot water to reduce the concentration of dissolved ions in the solution and expose the fresh surface of silver and other base metals to facilitate the next stage reaction. The acid concentration changes from dilute to concentrated as the reaction proceeds;

[0019] S6: The deposited gold mud is fully washed and filtered with hot water, and then flux is added to melt and cast into gold ingots;

[0020] Gold recovery technology from subgrade ore heap leaching

[0021] S1: drying the high-gold-containing filter residue produced by the high-grade ore leaching and gold recovery process and adding lime to the low-grade ore for ashing treatment;

[0022] S2: the high-gold-containing filter residue and the inferior raw ore which have been ashed in step S1 are piled up in a heap leaching field, and then the cyanide gold-containing lean liquid generated in the process of leaching and recovering gold from the high-grade raw ore is sprayed to generate gold-containing precious liquid and gold-containing filter residue;

[0023] S3: electrolyzing the gold-containing precious liquid to form gold mud and electrolyzing the lean liquid, and the generated gold mud is simultaneously processed with the gold mud generated by the high-grade raw ore leaching and gold recovery process;

[0024] S4: The gold-containing filter residue is put into the nitrate solution produced after the gold mud is washed in the high-grade raw ore leaching and gold recovery process. The tail gas generated by the reaction of the residual base metals in the gold-containing filter residue with the residual nitric acid in the nitrate is sprayed and absorbed by the flue, fan, and multi-stage absorption tower, and finally discharged through the tail gas chimney. The residual silver and other base metals in the gold-containing filter residue react with the residual nitric acid, which on the one hand neutralizes the acidity of the nitrate, and on the other hand further removes the base metal impurities in the gold-containing filter residue from the gold mud. The generated precipitated gold mud is simultaneously treated with the precipitated gold mud generated by the high-grade raw ore leaching and gold recovery process;

[0025] Intermediate product processing

[0026] S1: The electrolytic barren liquid generated by the process of recovering gold from heap leaching of inferior ore is mixed with the tail liquid generated by washing gold mud, and the tail gas generated by the process of recovering gold from leaching of high-grade ore is introduced into the mixture, and then carbide slag is added thereto, and stirred, and filtered by a Fengshui washing filter press to obtain gold ore residue and calcified liquid, and the gold ore residue is transported to the heap leaching site for heap leaching, and the heap leaching process for recovering gold is carried out with inferior ore;

[0027] S2: introducing carbon dioxide into the calcified liquid and stirring to perform decalcification treatment, and obtaining a decalcified liquid after carbonate precipitation;

[0028] S3: adding polyferric sulfate, ferric chloride and calcium sulfate to the decalcified liquid and stirring, so that the base metal cations in the decalcified liquid form sulfate precipitation to obtain a purified liquid;

[0029] S4: adding ammonium chloride to the purified liquid and stirring the mixture to generate hydrochloride and a deeply purified liquid;

[0030] S5: Sodium hydroxide is added to the deeply purified liquid to adjust the pH, and the purified cyanide gold-containing lean liquid is returned for recycling and used for high-grade raw ore heap leaching to recover gold. Process step S1 is used for high-grade raw ore preleaching, that is, the tail gas and tail liquid are recycled after neutralization reaction.

[0031] The beneficial effects of the present invention are as follows: the present invention, through the crushing and screening process, on the one hand, crushes and screens the gold ore raw materials, screens out the non-metallic minerals therein and uses them as sand and gravel raw materials, thereby reducing the consumption of non-metallic minerals in the gold recovery process for materials required for gold recovery; on the other hand, crushing is conducive to the full contact of the gold ore raw materials with sodium cyanide, thereby improving the recovery rate of the gold ore.

[0032] In the process of leaching and recovering gold from high-grade ore, the cyanide-containing gold-bearing lean liquid produced after washing with carbon stripping screen is used instead of directly spraying the low-grade ore with sodium cyanide. Although the accumulation and enrichment of associated gold minerals in the cyanide-containing gold-bearing lean liquid will have a certain impact on the gold recovery by spraying the low-grade ore, the use of cyanide-containing gold-bearing lean liquid instead of directly spraying the low-grade ore with sodium cyanide reduces the consumption of sodium cyanide and reduces the economic cost of gold recovery. In addition, since the gold content in the low-grade ore is relatively lower than that in the high-grade ore, the accumulation and enrichment of the cyanide-containing gold-bearing lean liquid will further reduce the impact of the low-grade ore spraying on the gold recovery.

[0033] The cyanide gold-containing lean solution is sprayed on the secondary ore to avoid the continuous accumulation and enrichment of impurity ions in the cyanide gold-containing lean solution, which is directly recycled for leaching of high-grade ore, resulting in an increase in the smelting cost of the gold mud produced by leaching of high-grade ore.

[0034] The tail gas electrolysis lean liquid that accumulates and enriches impurity ions through the gold recovery process of sub-grade raw ore heap leaching increases the concentration of impurity ions, making it easier to extract base metals other than gold from gold mines through the intermediate product processing process;

[0035] The electrolytic lean liquid produced after the electrolysis of the gold-containing precious liquid is treated through the intermediate product treatment process to remove the impurity ions enriched in the electrolytic lean liquid. At the same time, in the process of treating the electrolytic lean liquid, the tail gas and tail liquid produced in the high-grade ore leaching and gold recovery process are neutralized, reducing the impact of the tail gas on the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying figure is a work flow chart of gold recovery by leaching process; DETAILED DESCRIPTION

[0037] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments:

[0038] As shown in the figure, a method for recovering gold by leaching process specifically includes crushing and screening process, high-grade ore leaching gold recovery process, sub-grade ore heap leaching gold recovery process, and intermediate product processing process;

[0039] Crushing and screening process

[0040] S1: The gold ore is crushed by the primary crusher and then crushed by the secondary crusher. The products after the initial crushing are screened by a single-layer circular vibrating screen. The products on the screen are fed to the secondary crusher by a belt conveyor for further crushing. The products under the screen are the ore that has been crushed.

[0041] S2: The ore after the crushing process in step S1 is fed into the ball mill, and the ore discharged from the ball mill enters the classifier. The sand returned by the classifier is returned to the ball mill for re-grinding, and the overflow of the classifier completes the grinding;

[0042] S3: The ore ground in step S2 is fed into a magnetic separator for magnetic separation and screening to select low-grade ore pulp, medium-grade ore pulp and high-grade ore pulp. The low-grade ore is used as a raw material for construction sand and gravel after pre-discharging tailings.

[0043] High-grade ore leaching and gold recovery process

[0044] S1: The high-grade raw ore pulp flows by gravity to the thickener for pre-leaching concentration. The bottom flow of the thickener is pumped to the mixing tank by a pump. Sodium cyanide is added to the mixer for pre-leaching to obtain cyanide gold-containing precious liquid and high-gold filter residue;

[0045] S2: Add activated carbon to the cyanide gold-containing precious liquid. The activated carbon moves forward against the slurry flow. After being washed by the carbon extraction screen, the activated carbon adsorbs the gold ore in the cyanide gold-containing precious liquid to obtain gold-loaded carbon. At the same time, the gold content in the cyanide gold-containing precious liquid is reduced to be used as the cyanide gold-containing lean liquid.

[0046] S3: After being washed with water, the gold-loaded carbon enters the desorption column for high-temperature and high-pressure cyanide-free desorption. The desorbent is a sodium hydroxide solution. During the desorption, the electrolytic cell is turned on for electrolysis, so that the gold in the filtrate is enriched in the electrolytic cell to form gold mud. The filtrate without gold becomes electrolytic lean liquid and returns to the analytical column to continue desorption and elution of the gold-loaded carbon.

[0047] S4: washing the gold mud to remove the tail liquid consisting of sodium cyanide, sodium hydroxide and a small amount of chloride ions remaining in the gold mud during the desorption electrolysis process;

[0048] S5: The washed gold mud is acid-soaked in dilute nitric acid, and the generated tail gas (the base metals in the gold mud react with nitric acid during the acid-soaking operation to generate nitrogen oxide gas. Due to the violent reaction, bubbles are generated, and the nitrogen oxides and the materials splashed by the bubble bursting together constitute the tail gas) is sprayed and absorbed by the flue, fan, and multi-stage absorption tower, and finally discharged through the tail gas chimney. The silver and other base metals in the gold mud react with nitric acid to generate soluble nitrates that enter the solution, while gold does not react with nitric acid and is deposited in a solid state at the bottom of the reaction vessel to form precipitated gold mud, and the base metal impurities are removed from the gold mud;

[0049] Nitric acid is added in stages, and before adding acid in each stage, the product of the previous stage reaction is washed 2-3 times with hot water to reduce the concentration of dissolved ions in the solution and expose the fresh surface of silver and other base metals to facilitate the next stage reaction. The acid concentration changes from dilute to concentrated as the reaction proceeds;

[0050] S6: The deposited gold mud is fully washed and filtered with hot water, and then flux is added to melt and cast into gold ingots;

[0051] Gold recovery technology from subgrade ore heap leaching

[0052] S1: drying the high-gold-containing filter residue produced by the high-grade ore leaching and gold recovery process and adding lime to the low-grade ore for ashing treatment;

[0053] S2: the high-gold-containing filter residue and the inferior raw ore which have been ashed in step S1 are piled up in a heap leaching field, and then the cyanide gold-containing lean liquid generated in the process of leaching and recovering gold from the high-grade raw ore is sprayed to generate gold-containing precious liquid and gold-containing filter residue;

[0054] S3: electrolyzing the gold-containing precious liquid to form gold mud and electrolyzing the lean liquid, and the generated gold mud is simultaneously processed with the gold mud generated by the high-grade raw ore leaching and gold recovery process;

[0055] S4: The gold-containing filter residue is put into the nitrate solution produced after the gold mud is washed in the high-grade raw ore leaching and gold recovery process. The tail gas generated by the reaction of the residual base metals in the gold-containing filter residue with the residual nitric acid in the nitrate is sprayed and absorbed by the flue, fan, and multi-stage absorption tower, and finally discharged through the tail gas chimney. The residual silver and other base metals in the gold-containing filter residue react with the residual nitric acid, which on the one hand neutralizes the acidity of the nitrate, and on the other hand further removes the base metal impurities in the gold-containing filter residue from the gold mud. The generated precipitated gold mud is simultaneously treated with the precipitated gold mud generated by the high-grade raw ore leaching and gold recovery process;

[0056] Intermediate product processing

[0057] S1: The electrolytic barren liquid generated by the process of recovering gold from heap leaching of inferior ore is mixed with the tail liquid generated by washing gold mud, and the tail gas generated by the process of recovering gold from leaching of high-grade ore is introduced into the mixture, and then carbide slag is added thereto, and stirred, and filtered by a Fengshui washing filter press to obtain gold ore residue and calcified liquid, and the gold ore residue is transported to the heap leaching site for heap leaching, and the heap leaching process for recovering gold is carried out with inferior ore;

[0058] S2: introducing carbon dioxide into the calcified liquid and stirring to perform decalcification treatment, and obtaining a decalcified liquid after carbonate precipitation;

[0059] S3: adding polyferric sulfate, ferric chloride and calcium sulfate to the decalcified liquid and stirring, so that the base metal cations in the decalcified liquid form sulfate precipitation to obtain a purified liquid;

[0060] S4: adding ammonium chloride to the purified liquid and stirring the mixture to generate hydrochloride and a deeply purified liquid;

[0061] S5: Sodium hydroxide is added to the deeply purified liquid to adjust the pH, and the purified cyanide gold-containing lean liquid is returned for recycling and used for high-grade raw ore heap leaching to recover gold. Process step S1 is used for high-grade raw ore preleaching, that is, the tail gas and tail liquid are recycled after neutralization reaction.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for recovering gold by leaching process, specifically comprising a crushing and screening process, a high-grade ore leaching process for recovering gold, a sub-grade ore heap leaching process for recovering gold, and an intermediate product processing process; characterized in that: The crushing and screening process is as follows: S1: The gold ore is crushed by the primary crusher and then crushed by the secondary crusher. The products after the initial crushing are screened by a single-layer circular vibrating screen. The products on the screen are fed to the secondary crusher by a belt conveyor for further crushing. The products under the screen are the ore that has been crushed. S2: The ore after the crushing process in step S1 is fed into the ball mill, and the ore discharged from the ball mill enters the classifier. The sand returned by the classifier is returned to the ball mill for re-grinding, and the overflow of the classifier completes the grinding; S3: The ore ground in step S2 is fed into a magnetic separator for magnetic separation and screening to select low-grade ore pulp, medium-grade ore pulp and high-grade ore pulp. The low-grade ore is used as a raw material for construction sand and gravel after pre-discharging tailings. The process of leaching and recovering gold from high-grade raw ore is as follows: S1: The high-grade raw ore pulp flows by gravity to the thickener for pre-leaching concentration. The bottom flow of the thickener is pumped to the mixing tank by a pump. Sodium cyanide is added to the mixer for pre-leaching to obtain cyanide gold-containing precious liquid and high-gold filter residue; S2: Add activated carbon to the cyanide gold-containing precious liquid. The activated carbon moves forward against the slurry flow. After being washed by the carbon extraction screen, the activated carbon adsorbs the gold ore in the cyanide gold-containing precious liquid to obtain gold-loaded carbon. At the same time, the gold content in the cyanide gold-containing precious liquid is reduced to be used as the cyanide gold-containing lean liquid. S3: After being washed with water, the gold-loaded carbon enters the desorption column for high-temperature and high-pressure cyanide-free desorption. The desorbent is a sodium hydroxide solution. During the desorption, the electrolytic cell is turned on for electrolysis, so that the gold in the filtrate is enriched in the electrolytic cell to form gold mud. The filtrate without gold becomes electrolytic lean liquid and returns to the analytical column to continue desorption and elution of the gold-loaded carbon. S4: washing the gold mud to remove the tail liquid consisting of sodium cyanide, sodium hydroxide and a small amount of chloride ions remaining in the gold mud during the desorption electrolysis process; S5: The washed gold mud is acid-soaked in dilute nitric acid, and the generated tail gas (the base metals in the gold mud react with nitric acid during the acid-soaking operation to generate nitrogen oxide gas. Due to the violent reaction, bubbles are generated, and the nitrogen oxides and the materials splashed by the bubble bursting together constitute the tail gas) is sprayed and absorbed by the flue, fan, and multi-stage absorption tower, and finally discharged through the tail gas chimney. The silver and other base metals in the gold mud react with nitric acid to generate soluble nitrates that enter the solution, while gold does not react with nitric acid and is deposited in a solid state at the bottom of the reaction vessel to form precipitated gold mud, and the base metal impurities are removed from the gold mud; Nitric acid is added in stages, and before adding acid in each stage, the product of the previous stage reaction is washed 2-3 times with hot water to reduce the concentration of dissolved ions in the solution and expose the fresh surface of silver and other base metals to facilitate the next stage reaction. The acid concentration changes from dilute to concentrated as the reaction proceeds; S6: The deposited gold mud is thoroughly washed and filtered with hot water, and then flux is added to melt and cast into gold ingots.

2. The method for recovering gold by leaching process according to claim 1, characterized in that: The process for recovering gold by heap leaching of sub-grade ore is as follows: S1: drying the high-gold-containing filter residue produced by the high-grade ore leaching and gold recovery process and adding lime to the low-grade ore for ashing treatment; S2: the high-gold-containing filter residue and the inferior raw ore which have been ashed in step S1 are piled up in a heap leaching field, and then the cyanide gold-containing lean liquid generated in the process of leaching and recovering gold from the high-grade raw ore is sprayed to generate gold-containing precious liquid and gold-containing filter residue; S3: electrolyzing the gold-containing precious liquid to form gold mud and electrolyzing the lean liquid, and the generated gold mud is simultaneously processed with the gold mud generated by the high-grade raw ore leaching and gold recovery process; S4: The gold-containing filter residue is put into the nitrate solution produced after the gold mud is washed in the high-grade raw ore leaching and gold recovery process. The residual base metals in the gold-containing filter residue react with the residual nitric acid in the nitrate to produce tail gas that is absorbed by the spraying of the flue, fan, and multi-stage absorption tower, and is finally discharged through the tail gas chimney. The residual silver and other base metals in the gold-containing filter residue react with the residual nitric acid, which on the one hand neutralizes the acidity of the nitrate, and on the other hand further removes the base metal impurities in the gold-containing filter residue from the gold mud. The produced precipitated gold mud is treated simultaneously with the precipitated gold mud produced by the high-grade raw ore leaching and gold recovery process.

3. The method for recovering gold by leaching process according to claim 1, characterized in that: The intermediate product processing process is as follows: S1: The electrolytic barren liquid generated by the process of recovering gold from heap leaching of inferior ore is mixed with the tail liquid generated by washing gold mud, and the tail gas generated by the process of recovering gold from leaching of high-grade ore is introduced into the mixture, and then carbide slag is added thereto, and stirred, and filtered by a Fengshui washing filter press to obtain gold ore residue and calcified liquid, and the gold ore residue is transported to the heap leaching site for heap leaching, and the heap leaching process for recovering gold is carried out with inferior ore; S2: introducing carbon dioxide into the calcified liquid and stirring to perform decalcification treatment, and obtaining a decalcified liquid after carbonate precipitation; S3: adding polyferric sulfate, ferric chloride and calcium sulfate to the decalcified liquid and stirring, so that the base metal cations in the decalcified liquid form sulfate precipitation to obtain a purified liquid; S4: adding ammonium chloride to the purified liquid and stirring the mixture to generate hydrochloride and a deeply purified liquid; S5: Sodium hydroxide is added to the deeply purified liquid to adjust the pH, and the purified cyanide gold-containing lean liquid is returned for recycling and used for high-grade raw ore heap leaching to recover gold. Process step S1 is used for high-grade raw ore preleaching, that is, the tail gas and tail liquid are recycled after neutralization reaction.

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