Method for green treatment of gold tailings

Abstract

The invention relates to a method for green treatment of gold tailings, and is applied to the technical field of precious metal recovery. The method comprises the steps that primary bacterial liquid spraying is conducted on tailings in a greenhouse of a gold tailing site, and the used bacterial liquid mainly fixes cyanide in the tailings and assists in digestion; transferring the tailings subjected to the first bacterial liquid spraying treatment from the shed to a target position by adopting a reaction tank; when the reaction tank is located at the target position, secondary bacterial liquid spraying is conducted on the tailings in the reaction tank, cyanide in the tailings is digested through the used bacterial liquid, third bacterial liquid spraying is conducted on the tailings in the reaction tank, and oxidation pretreatment, sulfur removal, arsenic removal and carbon removal are conducted on the tailings through the used bacterial liquid; after the tailings are sprayed with all the bacterial liquid, the tailings are subjected to microwave roasting and grinding, and water is added for size mixing; and the tailings obtained after size mixing are subjected to multiple times of physical separation, and gold concentrate is obtained. According to the scheme provided by the invention, no chemical agent is used in the recovery treatment process of the gold tailings, and the daily operation cost is remarkably reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of precious metal recovery, and in particular to a method for green treatment of gold tailings. BACKGROUND

[0002] The gold tailings resource utilization technology, i.e. the recovery of valuable components from tailings, can improve the added value of tailings products. The commonly used related technology at present is the combined gold extraction technology of "water washing cyanide removal + Nelson gravity separation + flotation column machine". This technology needs to use expensive chemical reagents such as flotation agents, and also needs other chemical reagents to treat cyanide-containing wastewater. In addition, the use amount of chemical reagents is large, most of which will pollute the environment, and the reprocessing of wastewater and tailings solids containing a large amount of chemical reagents is difficult and the process is complex, which has high cost. SUMMARY

[0003] To solve or partially solve the problems in the related art, the present application provides a method for green treatment of gold tailings, which can not use chemical reagents in the recovery and treatment process of gold tailings.

[0004] The first aspect of the present application provides a method for green treatment of gold tailings, comprising: After a shed house is built on the site of gold tailings, a first bacteria liquid spraying is performed on the tailings in the shed house, wherein the bacteria liquid used in the first bacteria liquid spraying mainly fixes cyanide in the tailings and secondarily digests the cyanide; A single or multiple reaction tanks are used to transfer the tailings treated by the first bacteria liquid spraying from the shed house to corresponding target positions; When the reaction tank is at the corresponding target position, a second bacteria liquid spraying is performed on the tailings in the reaction tank, wherein the bacteria liquid used in the second bacteria liquid spraying digests the cyanide in the tailings; When the reaction tank is at the corresponding target position, a third bacteria liquid spraying is performed on the tailings in the reaction tank, wherein the bacteria liquid used in the third bacteria liquid spraying performs oxidative pretreatment on the tailings to remove sulfur impurities, arsenic impurities and carbon impurities in the tailings; After all the bacteria liquid sprayings are performed on the tailings, the tailings are sequentially subjected to microwave roasting, grinding and water slurry preparation; The tailings after slurry preparation are subjected to multiple physical separations to obtain gold concentrates.

[0005] In combination with the first aspect of the present application, in an optional embodiment, the first bacteria liquid spraying on the tailings in the shed house comprises: Spray the tailings in the shed house with a first mixed bacteria solution, the first mixed bacteria solution comprising CG305-1 functional bacteria, LS-1 functional bacteria and composite bacteria TDB1+TCD1+Z90, wherein the ratio of CG305-1 functional bacteria and LS-1 functional bacteria is higher than that of composite bacteria TDB1+TCD1+Z90.

[0006] In combination with the first aspect of the application, in an optional embodiment, the tailings in the reaction tank are sprayed with a second bacteria solution, comprising: Spray the tailings in the reaction tank with a second mixed bacteria solution, the second mixed bacteria solution comprising CG305-1 functional bacteria, LS-1 functional bacteria and composite bacteria TDB1+TCD1+Z90, wherein the ratio of CG305-1 functional bacteria and LS-1 functional bacteria is lower than that of composite bacteria TDB1+TCD1+Z90; Stir the tailings in the reaction tank, and control the environmental parameters in the reaction tank to meet the optimal activity conditions of the second mixed bacteria solution.

[0007] In combination with the first aspect of the application, in an optional embodiment, the tailings in the reaction tank are sprayed with a third bacteria solution, comprising: Spray the tailings in the reaction tank with a pre-cultured HQ0211 leaching bacteria solution; Stir the tailings in the reaction tank, and control the environmental parameters in the reaction tank to meet the optimal activity conditions of the HQ0211 leaching bacteria solution.

[0008] In combination with the first aspect of the application, in an optional embodiment, the tailings after slurry preparation are subjected to multiple physical separations to obtain gold concentrate, comprising: The tailings after slurry preparation are subjected to multi-stage magnetic separation with different magnetic forces to obtain tail residue and gold concentrate slurry; The gold concentrate slurry is separated into first tailings slurry and high-concentration gold concentrate slurry using a separator; The high-concentration gold concentrate slurry is separated using a single or multiple series of shaking tables to obtain second tailings slurry and the gold concentrate.

[0009] In combination with the first aspect of the application, in an optional embodiment, the tailings after slurry preparation are subjected to multiple physical separations to obtain gold concentrate, further comprising: Before the tailings after slurry preparation are subjected to multi-stage magnetic separation with different magnetic forces, the tailings after slurry preparation are subjected to micro-porous screen bed screening to obtain coarse particle tail residue and fine particle slurry.

[0010] In combination with the first aspect of the present application, in an optional embodiment, the tailings after the pulp conditioning are subjected to multi-stage magnetic separation with different magnetic forces to obtain tailings and gold concentrate slurry, including: The first low-magnetic-force magnetic separation machine is used to perform low-magnetic-force primary separation on the fine-particle slurry to obtain first tailings slurry and first slurry; The second low-magnetic-force magnetic separation machine is used to perform low-magnetic-force re-separation on the first tailings slurry to obtain second tailings slurry and the gold concentrate slurry; The first high-magnetic-force magnetic separation machine is used to perform high-magnetic-force primary separation on the first slurry to obtain third tailings slurry and the gold concentrate slurry; The second high-magnetic-force magnetic separation machine is used to perform high-magnetic-force re-separation on the third tailings slurry to obtain fourth tailings slurry and the gold concentrate slurry; And, the second tailings slurry and the fourth tailings slurry are subjected to dewatering to obtain the tailings.

[0011] In combination with the first aspect of the present application, in an optional embodiment, the tailings after the pulp conditioning are subjected to multiple physical separations to obtain gold concentrate, further including: After obtaining the gold concentrate slurry, the first spin separator is used to perform centrifugal classification on the gold concentrate slurry to obtain third tailings slurry and classified gold concentrate slurry, and the classified gold concentrate slurry is separated into the first tailings slurry and the high-concentration gold concentrate slurry.

[0012] In combination with the first aspect of the present application, in an optional embodiment, the tailings after the pulp conditioning are subjected to multiple physical separations to obtain gold concentrate, further including: After separating the high-concentration gold concentrate slurry, the second spin separator is used to perform centrifugal classification on the high-concentration gold concentrate slurry to obtain fourth tailings slurry and classified high-concentration gold concentrate slurry, and the classified high-concentration gold concentrate slurry is separated into the second tailings slurry and the gold concentrate.

[0013] In combination with the first aspect of the present application, in an optional embodiment, further including: The first tailings slurry, the second tailings slurry, the third tailings slurry and the fourth tailings slurry are collected by a tailings slurry storage tank; The tailings slurry output by the tailings slurry storage tank is subjected to solid-liquid separation by a sewage treatment device to obtain purified water, and the purified water can be recycled.

[0014] The technical solution provided by the present application can include the following beneficial effects: The technical scheme of the present application is that a shed is built on the original site of the gold tailing pond, and bacteria liquid is sprayed on the tailings in the shed, the bacteria liquid used is mainly considered to fix cyanide so that it is not easy to spread, and cyanide is also digested, so that the cyanide-containing dust generated when the tailings are transported to the reaction tank is not easy to be absorbed by the human body; when the tailings are transported to the target position through a single or multiple reaction tanks, the tailings can be sprayed with two different bacteria liquids in the same reaction tank, the bacteria liquid sprayed first is used to completely digest the cyanide in the tailings, and the bacteria liquid sprayed later is used to oxidize the minerals, so as to realize desulfurization, dearsenification and decarburization of the tailings, the embodiment of the present application removes the toxins from the tailings in stages at the initial stage of gold recovery, provides a factual basis that no chemical agent is needed for subsequent process flow, and then the tailings after detoxification can be recovered in an environmentally friendly way through physical separation to obtain gold concentrate, and the pain points of the industry are solved.

[0015] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF DRAWINGS

[0016] The above and other objects, features and advantages of the present application will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout the several views, and in which the exemplary embodiments of the present application are shown.

[0017] Figure 1 is a flowchart of the method for green treatment of gold tailings shown in the embodiment of the present application; Figure 2 is a flowchart of step S103; Figure 3 is a flowchart of step S106; Figure 4 is a structural block diagram of the system for green treatment of gold tailings shown in the embodiment of the present application; In the figure: 11, shed; 12, loading car; 13, belt feeder; 14, trailer; 21, reaction tank; 22, microwave roasting furnace; 23, conveying belt; 24, microwave generator; 25, screw conveyor; 26, grinding machine; 27, double-screw mixing machine; 31, microporous sieve bed; 32, No. 1 slurry pump; 33, first low-magnetic-force magnetic separator; 34, second low-magnetic-force magnetic separator; 35, first high-magnetic-force magnetic separator; 36, second high-magnetic-force magnetic separator; 37, No. 1 concentrate slurry tank; 38, No. 1 dehydration screw machine; 39, No. 2 dehydration screw machine; 41, No. 2 slurry pump; 42, first cyclone; 43, separator; 44, No. 3 slurry pump; 45, second cyclone; 46, No. 2 concentrate slurry tank; 47, No. 4 slurry pump; 48, shaking table; 49, tailings slurry storage tank; 50, No. 5 slurry pump. DETAILED DESCRIPTION

[0018] Embodiments of the present application will be described in more detail with reference to the drawings. Although the embodiments of the present application are shown in the drawings, it is understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that the present application will be thorough and complete, and will fully convey the scope of the present application to those skilled in the art.

[0019] The terminology used in the present application is merely for the purpose of describing particular embodiments and is not intended to limit the present application. As used in the present application and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "and / or," as used herein, refer to and encompass any or all possible combinations of one or more of the associated listed items.

[0020] It should be understood that although the terms "first," "second," "third," etc. can be employed in this disclosure to describe various information, but these information should not be limited by these terms. These terms are only used to distinguish one piece of information from another piece of information of the same type. For example, the first information can also be called the second information, and similarly, the second information can also be called the first information without departing from the scope of the present application. Therefore, the features defined with "first," "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0021] The technical solutions of the embodiments of the present application are described in detail below in combination with the drawings.

[0022] Referring to Figure 1 and Figure 4 , the embodiments of the present application provide a method for green treatment of gold tailings, mainly comprising steps S101-S106.

[0023] Step S101: After a shed house 11 is built on the site of the gold tailings, a first bacterial liquid spraying is performed on the tailings in the shed house 11, wherein the bacterial liquid used in the first bacterial liquid spraying mainly fixes cyanide in the tailings and secondarily digests cyanide.

[0024] In step S101, the first bacterial liquid spraying is performed on the tailings in the shed house 11, further comprising: using a first mixed bacterial liquid prepared in advance to spray the tailings in the shed house 11, the first mixed bacterial liquid comprising CG305-1 functional bacteria, LS-1 functional bacteria and a composite bacterial group TDB1+TCD1+Z90, wherein the sum of the ratio of CG305-1 functional bacteria and LS-1 functional bacteria is higher than the composite bacterial group TDB1+TCD1+Z90.

[0025] In the present embodiment, a storage shed 11 is established at the site of the gold tailings (i.e., the gold tailings site), and a first mixed bacteria solution prepared in advance is used to preliminarily treat the tailings by spraying to reduce the toxicity of cyanide, the first mixed bacteria solution including three bacteria strains, one of which is CG305-1 functional bacteria, the second of which is LS-1 functional bacteria, and the third of which is a composite bacteria group TDB1+TCD1+Z90. These three bacteria strains are all aerobic bacteria. At present, the industrial use of these bacteria strains on the market is mostly the single application of a single bacteria strain, and the comprehensive use of each bacteria strain to exert its respective performance advantage is still relatively rare. The two bacteria strains of CG305-1 functional bacteria and LS-1 functional bacteria have stronger cyanide fixation effect while digesting cyanide, and therefore, it is appropriate to have a ratio of CG305-1 functional bacteria and LS-1 functional bacteria higher than that of the composite bacteria group TDB1+TCD1+Z90. Specifically, the ratio of the three bacteria strains can be 30wt%:30wt%:40wt%, and further, the storage shed 11 established at the gold tailings site is used to digest toxicity as an auxiliary function, and to fix the toxic substances and prevent them from spreading as the main consideration. In this way, after the detection meets the standard, the tailings are transported to the reaction tank 21 by using a loading vehicle 12 through a belt feeder 13, i.e., the tailings are transported to the reaction tank 21. The cyanide contained in the dust generated during the transportation process is not easily absorbed by the human body, and at the same time, the transportation process must strictly follow the national standard for dust handling by spraying water to reduce dust, so that the dust generated during the transportation of the tailings has no effect on the health of the on-site workers. Of course, with the progress of science and technology, in the future, unmanned mine vehicles can be used to replace the loading vehicle 12 and other vehicles to transfer the tailings from the storage shed 11 to the reaction tank 21.

[0026] Step S102: using a single or multiple reaction tanks 21 to transfer the tailings treated by the first bacteria solution spraying to the corresponding target position from the shed 11.

[0027] In the present embodiment, the reaction tank 21, i.e., the material reaction tank, can be arranged with 10-40 tanks according to the processing capacity of the tailings. The material reaction tank serves as the core place for subsequent bacteria solution spraying and needs to provide a suitable environment for the microbial flora. The material reaction tank can have a stirring function. For the function of stirring the tailings in the tank, it can ensure that the microbial flora and the tailings are fully and uniformly mixed, so that the microbial flora is evenly distributed in the tailings and the detoxification capacity of the microbial flora is improved. At the same time, the material reaction tank also has the functions of constant temperature, constant humidity and aeration. The aeration here refers to the injection of oxygen and air, so that the environmental parameters inside the material reaction tank can meet the best activity conditions for the survival and reproduction of microorganisms. For multiple material reaction tanks, in order to facilitate management, a corresponding station can be set for each material reaction tank for the implementation of spraying operations. The corresponding station is the corresponding target position. Preferably, the reaction tank 21 can be inclined with the material fed from the top and discharged from the bottom, which can improve the unloading efficiency of the tailings.

[0028] When the material reaction tank is used to transport tailings, the material reaction tank is installed on the trailer 14 and transported to the tailings site by the trailer 14 for loading. During the loading process, it is verified that the outlet of the material reaction tank is in a closed state, the inlet of the material reaction tank is controlled to be in an open state, the loading vehicle 12 loads the powdered tailings into the material reaction tank to a specified height through the belt feeder 13 on the site, and then the inlet is controlled to be in a closed state. The material reaction tank is transported to the processing workshop by the trailer 14, and then hoisted to the specified position by the rail-mounted crane.

[0029] Step S103: When the reaction tank 21 is in the corresponding target position, the tailings in the reaction tank 21 are sprayed with the second bacteria liquid, and the second bacteria liquid used to digest cyanide in the tailings.

[0030] As shown in FIG. 3, in step S103, the tailings in the reaction tank 21 are sprayed with the second bacteria liquid, which can further include steps 301 and 302. Figure 2

[0031] Step 301: The tailings in the reaction tank 21 are sprayed with the second mixed bacteria liquid prepared in advance, and the second mixed bacteria liquid includes CG305-1 functional bacteria, LS-1 functional bacteria and composite bacteria group TDB1+TCD1+Z90, wherein the sum of the ratio of CG305-1 functional bacteria and LS-1 functional bacteria is less than the composite bacteria group TDB1+TCD1+Z90.

[0032] In step S301, the second mixed bacteria liquid and the first mixed bacteria liquid involve the same bacteria, but the ratio is different, wherein the sum of the ratio of CG305-1 functional bacteria and LS-1 functional bacteria is less than the composite bacteria group TDB1+TCD1+Z90, for example, the ratio of CG305-1 functional bacteria, LS-1 functional bacteria and composite bacteria group TDB1+TCD1+Z90 can be 30wt%:30wt%:40wt%. The ratio of the composite bacteria group TDB1+TCD1+Z90 is relatively higher, and using more composite bacteria group TDB1+TCD1+Z90 can improve the cyanide digestion capacity, and then completely decyanate the tailings in the material reaction tank.

[0033] Step 302: The tailings in the reaction tank 21 are stirred, and the environmental parameters in the reaction tank 21 are controlled to meet the optimal activity conditions of the second mixed bacteria liquid.

[0034] ​In order to improve the detoxification ability of the microbial strain, a suitable survival environment needs to be provided for the microbial strain, for example, the environmental temperature is 20°C-28°C, the humidity is 80%, and the oxygen content is 21% of the volume fraction of oxygen in the air. In addition, stirring can ensure that the microbial flora and the tailings are fully and uniformly mixed, so that the microbial flora is uniformly distributed in the tailings, and the detoxification ability of the microbial flora is improved.

[0035] It should be noted that steps S301 and S302 in step 103 are not limited to the order, and the material reaction tank is always in a stirring state in the whole step S103.

[0036] Step S104: When the reaction tank 21 reaches the corresponding target position, the tailings in the reaction tank 21 are sprayed with the third bacteria liquid. The bacteria liquid used in the third bacteria liquid spraying is used for oxidative pretreatment of the tailings, and the sulfur impurities, arsenic impurities and carbon impurities in the tailings are removed.

[0037] In step S104, the tailings in the reaction tank 21 are sprayed with the third bacteria liquid, which can further include: using the pre-trained HQ0211 leaching bacteria liquid to spray the tailings in the reaction tank 21; stirring the tailings in the reaction tank 21, and controlling the environmental parameters in the reaction tank 21 to meet the optimal activity conditions of the HQ0211 leaching bacteria liquid.

[0038] The sub-steps in step S104 are basically the same as the sub-steps in step S103, except that the second mixed bacteria liquid is different from the HQ0211 leaching bacteria liquid. Step S103 aims to remove cyanide from the tailings, and step S104 aims to oxidize the tailings to achieve desulfurization, dearsenization and decarburization of the tailings. The two together with the first spraying form a new microbial detoxification method.

[0039] Both steps S103 and S104 are implemented in the material reaction tank, and the respective reference running time is 96 hours. After the operation of each stage is completed, whether the respective detection index meets the standard needs to be detected. When the detection meets the standard, the next step can be entered, otherwise the operation of the current step continues.

[0040] Step S105: After all the bacteria liquid is sprayed on the tailings, the tailings are sequentially subjected to microwave roasting, grinding and water slurry.

[0041] Obviously, steps S101-S104 complete the detoxification treatment of the tailings, and the tailings after step S104 are non-toxic, which provides a factual basis for subsequent physical separation, and the tailings can be treated in a green and environmentally friendly manner without using chemical reagents.

[0042] Before separating the tailings, they need to be ground and slurryed. In order to improve the degree of damage to the gold particles' coatings during grinding, the tailings can be pre-treated, such as roasting. If necessary, harmful gases that may be generated in the microwave roasting furnace 22 can be adsorbed and removed during roasting. By controlling the time and temperature of microwave roasting of the tailings, cracks can be formed in the coatings on the gold particles and harmful gases can be avoided. In particular, the roasting process can also dry the microorganisms and bacteria on the solid particles in the tailings, destroy the hyphae adhesion between the solid particles, and make it difficult for the solid particles to stick together, thereby making it easy to separate the solid particles.

[0043] The microwave roasting furnace 22 is equipped with a conveyor belt 23 and a microwave generator 24. The microwave generator 24 is located above the conveyor belt 23. The first end of the conveyor belt 23 receives tailings from the material reaction tank through the inlet of the microwave roasting furnace 22. The microwave roasting furnace 22 is also equipped with a spiral conveyor 25, which is used to receive tailings that slide down from the end of the conveyor belt 23 and discharge them into the grinding mill 26.

[0044] In step S105, the material reaction vessel is transported to the feed inlet of the microwave roasting furnace 22 by a trailer 14. The inclined material reaction vessel allows the tailings to quickly enter the microwave roasting furnace 22 by gravity during the unloading process. The tailings are roasted using the microwave roasting furnace 22, and then the roasted tailings are fed into the grinder 26 via a screw conveyor 25. The grinder 26 grinds the tailings to 300-400 mesh, with fine tailings containing more than 50% 0.037mm particles to ensure separation of gold microparticles from encapsulated materials. The fine tailings discharged from the grinder 26 then enter the twin-screw slurry conditioner 27 for slurry preparation by adding water (10wt%-25wt%).

[0045] After the tailings in the material reaction tank are unloaded, the material reaction tank can be transported back to the tailings site by trailer 14 for reloading, detoxification and unloading.

[0046] Step S106: Perform multiple physical separations on the tailings after slurry preparation to obtain gold concentrate.

[0047] like Figure 3 As shown, in some embodiments, step S106 may further include steps S601 to S606.

[0048] Step S601: The tailings after slurry conditioning are screened using a microporous screen bed 31 to obtain coarse tailings and fine slurry. In this embodiment, a microporous screen bed 31 is used to screen the tailings after water conditioning. The coarse tailings screened out by the screen bed are discharged by the corresponding belt conveyor 13 to form a stockpile. The stockpile is then transported to the tailings area for backfilling or sale.

[0049] Step S602: The fine particle slurry obtained in step S601 is subjected to multi-stage magnetic separation with different magnetic forces to obtain tailings and gold concentrate slurry.

[0050] In at least one embodiment, step S602 can be: using a first low magnetic force magnetic separator 33 to perform low magnetic force primary separation on the fine particle slurry to obtain first tailings slurry and first slurry; using a second low magnetic force magnetic separator 34 to perform low magnetic force re-separation on the first tailings slurry to obtain second tailings slurry and gold concentrate slurry; using a first high magnetic force magnetic separator 35 to perform high magnetic force primary separation on the first slurry to obtain third tailings slurry and gold concentrate slurry; using a second high magnetic force magnetic separator 36 to perform high magnetic force re-separation on the third tailings slurry to obtain fourth tailings slurry and gold concentrate slurry; and dehydrating the second tailings slurry and the fourth tailings slurry to obtain tailings.

[0051] In this embodiment, the slurry outlet of the microporous sieve bed 31 is connected to the inlet of the first low magnetic force magnetic separator 33 through the No. 1 slurry pump 32; one outlet of the first low magnetic force magnetic separator 33 is connected to the inlet of the second low magnetic force magnetic separator 34, and the other outlet is connected to the inlet of the first high magnetic force magnetic separator 35; one outlet of the second low magnetic force magnetic separator 34 is connected to the No. 1 dehydration screw machine 38, and the other outlet is connected to the No. 1 concentrate slurry tank 37; one outlet of the first high magnetic force magnetic separator 35 is connected to the inlet of the second high magnetic force magnetic separator 36, and the other outlet is connected to the No. 1 concentrate slurry tank 37; one outlet of the second high magnetic force magnetic separator 36 is connected to the No. 2 dehydration screw machine 39, and the other outlet is connected to the No. 1 concentrate slurry tank 37. Among them, the No. 1 dehydration screw machine 38 and the No. 2 dehydration screw machine 39 respectively dehydrate the tailings slurry to obtain tailings, and the obtained tailings are discharged through the respective belt feeders 13.

[0052] Obviously, the fine particle slurry after being separated by the sieve bed in this embodiment is pumped into the magnetic separation section by the No. 1 slurry pump 32 for two-stage magnetic force separation with low magnetic force and high magnetic force, wherein two magnetic separators are used for primary separation and re-separation in each stage of magnetic force separation. The slurry corresponding to the re-separation process in the low magnetic force separation and the primary separation process and the re-separation process in the high magnetic force separation is discharged into the No. 1 concentrate slurry tank 37. The tailings slurry containing magnetic minerals corresponding to the re-separation process in each stage of magnetic force separation is discharged to the respective dehydration screw machine, and the tailings slurry therein is dehydrated by the dehydration screw machine to obtain tailings, which are then discharged through the corresponding belt feeder 13 to obtain the heap, and the obtained heap with high iron content is loaded and sold, or can be transported to the tailings area for direct backfilling.

[0053] Step S603: The gold concentrate slurry is subjected to centrifugal classification using a first cyclone 42 to obtain third tailings slurry and classified gold concentrate slurry.

[0054] The No. 1 concentrate pulp tank 37 is connected to the first cyclone 42 through the No. 2 slurry pump 41, one outlet of the first cyclone 42 is connected to the tailing pulp storage tank 49, and the other outlet is connected to the inlet of the separator 43. Therefore, the gold concentrate pulp after magnetic separation is pumped into the first cyclone 42 by the No. 2 slurry pump 41 for centrifugal classification, and the third tailing pulp and the classified gold concentrate pulp are separated. The classified gold concentrate pulp enters the separator 43 under the action of gravity through the other outlet, and the third tailing pulp enters the tailing pulp storage tank 49 through the one outlet.

[0055] Step S604: The first tailing pulp and the high-concentration gold concentrate pulp are separated from the classified gold concentrate pulp obtained in step S603 using the separator 43.

[0056] Taking the number of the separator 43 as one, the inlet of the separator 43 is connected to the other outlet of the first cyclone 42, one outlet of the separator 43 is connected to the sewage storage tank 49, and the other outlet is connected to the second cyclone 45 through the No. 3 slurry pump 44. The gold concentrate pulp separated by the first cyclone 42 enters the separator 43 under the action of gravity, and the high-concentration gold concentrate pulp is further separated using the separator 43.

[0057] If the number of the separator 43 is multiple, the multiple separators 43 can be connected in parallel, that is, the inlets of the multiple separators 43 are all connected to the other outlet of the first cyclone 42, and the other corresponding outlets are the same, that is, one outlet is connected to the tailing pulp storage tank 49, and the other outlet is connected to the second cyclone 45 through the No. 3 slurry pump 44. The multiple separators 43 can also be connected in series, and the gold concentrate pulp separated each time enters the next separator 43, and the corresponding tailing pulp enters the tailing pulp storage tank 49. The specific selection can be made according to the actual situation.

[0058] Step S605: The high-concentration gold concentrate pulp is centrifugally classified using the second cyclone 45 to obtain the fourth tailing pulp and the classified high-concentration gold concentrate pulp. One outlet of the second cyclone 45 is connected to the tailing pulp storage tank 49, and the other outlet is above the inlet of the No. 2 concentrate pulp tank 46 for the classified high-concentration gold concentrate pulp to enter. The outlet of the No. 2 concentrate pulp tank 46 is connected to the inlet of the shaking table 48 through the No. 4 slurry pump 47. The high-concentration gold concentrate pulp is pumped into the second cyclone 45 by the No. 3 slurry pump 44 for centrifugal classification, and the fourth tailing pulp flows into the tailing pulp storage tank 49. The classified high-concentration gold concentrate pulp is collected in the No. 2 concentrate pulp tank 46, and the high-concentration gold concentrate pulp in the No. 2 concentrate pulp tank 46 is pressurized by the No. 4 slurry pump 47 and sent to the shaking table 48.

[0059] Step S606: using a single or multiple series of shaking tables 48 to separate the high concentration gold concentrate slurry obtained from step S605 to obtain a second tailing slurry and gold concentrate. In this embodiment, the number of shaking tables 48 is two, the two shaking tables 48 are series connected, the gold concentrate separated by the first shaking table 48 enters the second shaking table 48, and the corresponding tailing slurry enters the tailing slurry storage tank 49. Among them, the shaking table 48 is used to separate and recover extremely fine gold particles, the recovered gold particles can reach 5-10 microns, and the required gold concentrate particles are collected at the mineral outlet end of the second shaking table 48, that is, the green recovery of gold is realized.

[0060] In at least one embodiment, the embodiment of the present application can also include: collecting the first tailing slurry, the second tailing slurry, the third tailing slurry and the fourth tailing slurry through the tailing slurry storage tank 49; using a sewage treatment device to separate the tailing slurry output by the tailing slurry storage tank 49 to obtain purified water, which can be recycled.

[0061] The first tailing slurry, the second tailing slurry, the third tailing slurry and the fourth tailing slurry are collected through the tailing slurry storage tank 49, and the tailing slurry in the tailing slurry storage tank 49 is pressurized by using the No. 5 mud pump 50 to enter the sewage treatment device, so that the tailing slurry is separated by using the sewage treatment device, and the purified water can be recycled. The use of fresh water can be significantly reduced in this method. The tailing slurry collected by the tailing slurry storage tank 49 has been detoxified and treated, and there is no need to use chemical agents such as flocculating agents for sedimentation treatment of the tailing slurry. The collected tailing slurry can be treated by purchasing a water treatment product with the ability to physically separate fine solid particles. The treated water that meets the standards without chemical agents is all recycled and used, and the water cost is low.

[0062] In this embodiment, between the microwave roasting and the grinding machine 26, the spiral conveyor 25 at the outlet of the microwave roasting furnace 22 has the ability to automatically discharge tailings. The spiral conveyor 25 can transport the tailings after roasting into the spiral conveyor 25 to the grinding machine 26, and the fine particle tailings obtained by grinding are automatically transported to the double screw mud mixer 27. The double screw mud mixer 27 adds water to the fine particle tailings to adjust the slurry. The subsequent treatment is the treatment of the slurry, which enters the next process by the pressure of the mud pump or the self-gravity of the slurry. It can be said that the implementation of the subsequent process of the microwave roasting process realizes automatic control, greatly reducing the work burden of the operator.

[0063] More importantly, the embodiment of the present application first applies microbial technology to remove toxic cyanide and pre-oxidized tailings to remove sulfur, arsenic and carbon, and a physical separation method without any chemical agent is used for the ground tailings, and green and environmentally friendly gold particles are separated, the tailings discharged in this process are completely free of chemical agent pollution, safe and non-toxic, and can be directly sold for the construction industry, or the tailings can be further developed for organic soil regeneration. In addition, the embodiment of the present application combines detoxification treatment of toxic substances in stages and physical separation treatment of non-toxic tailings, which can greatly reduce the daily operating cost of treating cyanide-containing tailings, effectively reduce the inventory of gold tailings, free up space for new gold tailings, and enable the mine to continue mining and production, and the tailings slurry without chemical agents can be conveniently recycled and reused, greatly improving the comprehensive utilization rate of resources in the mining area, and comprehensively solving the difficulties and pain points of the gold ore dressing industry.

[0064] As Figure 4 shown, the embodiment of the present application can also provide a system for green treatment of gold tailings, and the composition of the system is mainly based on the equipment involved in the method for green treatment of gold tailings, Figure 4 The equipment involved in each step of the method can be derived from the shelf product, or can be an adaptive modification of the shelf product to meet the implementation of each step, or can be a self-researched device to meet the implementation of each step, based on which the embodiment of the present application will not be described in detail.

[0065] The above has described the embodiments of the present application, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes are obvious to those skilled in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles, practical applications or improvements to the technology in the market of the embodiments, or to enable other ordinary skilled persons in the art to understand the embodiments disclosed herein.

Claims

1. A method of green processing of gold tailings, characterized by, The method comprises the following steps: After a shed house is built on a gold tailing site, a first bacteria liquid spraying is performed on the tailings in the shed house, wherein the bacteria liquid used in the first bacteria liquid spraying mainly fixes cyanide in the tailings and secondarily digests the cyanide; The single or multiple reaction tanks are used to transfer the tailings treated by the first bacteria liquid spraying from the shed house to corresponding target positions; When the reaction tanks are at the corresponding target positions, a second bacteria liquid spraying is performed on the tailings in the reaction tanks, wherein the bacteria liquid used in the second bacteria liquid spraying digests cyanide in the tailings; When the reaction tanks are at the corresponding target positions, a third bacteria liquid spraying is performed on the tailings in the reaction tanks, wherein the bacteria liquid used in the third bacteria liquid spraying performs an oxidation pretreatment on the tailings to remove sulfur impurities, arsenic impurities and carbon impurities in the tailings; After all the bacteria liquid sprays are performed on the tailings, the tailings are sequentially subjected to microwave roasting, grinding and water slurry preparation; The tailings after the slurry preparation are subjected to multiple physical separations to obtain gold concentrates.

2. The method of green processing of gold tailings as claimed in claim 1 wherein, The first bacteria liquid spraying on the tailings in the shed house comprises the following steps: The first mixed bacteria liquid prepared in advance is used to spray the tailings in the shed house, the first mixed bacteria liquid comprising CG305-1 functional bacteria, LS-1 functional bacteria and a composite bacterial group TDB1+TCD1+Z90, wherein the sum of the ratio of the CG305-1 functional bacteria and the LS-1 functional bacteria is higher than that of the composite bacterial group TDB1+TCD1+Z90.

3. The method of green processing of gold tailings as claimed in claim 1 wherein, The second bacteria liquid spraying on the tailings in the reaction tank comprises the following steps: The second mixed bacteria liquid prepared in advance is used to spray the tailings in the reaction tank, the second mixed bacteria liquid comprising CG305-1 functional bacteria, LS-1 functional bacteria and a composite bacterial group TDB1+TCD1+Z90, wherein the sum of the ratio of the CG305-1 functional bacteria and the LS-1 functional bacteria is lower than that of the composite bacterial group TDB1+TCD1+Z90; The tailings in the reaction tank are stirred, and the environmental parameters in the reaction tank are controlled to meet the optimal activity conditions of the second mixed bacteria liquid.

4. The method of green processing of gold tailings as claimed in claim 1 wherein, The third bacteria liquid spraying on the tailings in the reaction tank comprises the following steps: The HQ0211 leaching bacteria liquid trained in advance is used to spray the tailings in the reaction tank; The tailings in the reaction tank are stirred, and the environmental parameters in the reaction tank are controlled to meet the optimal activity conditions of the HQ0211 leaching bacteria liquid.

5. The method of green processing of gold tailings as claimed in claim 1 wherein, The multiple physical separations of the tailings after the slurry preparation to obtain gold concentrates comprise the following steps: The tailings after the slurry preparation are subjected to multi-stage magnetic separation with different magnetic forces to obtain tail residues and gold concentrate slurry; The separator is used to separate the first tailing slurry and high-concentration gold concentrate slurry from the gold concentrate slurry; The single or multiple series shaking tables are used to separate the high-concentration gold concentrate slurry to obtain second tailing slurry and the gold concentrate.

6. The method of green processing of gold tailings as claimed in claim 5 wherein, The multiple physical separations of the tailings after the slurry preparation to obtain gold concentrates further comprise the following steps: Before the multi-stage magnetic separation with different magnetic forces is performed on the tailings after the slurry preparation, the tailings after the slurry preparation are subjected to micro-porous sieve bed screening to obtain coarse-particle tail residues and fine-particle slurry.

7. The method of green processing of gold tailings as claimed in claim 6 wherein, The tailings after the pulp conditioning are subjected to multi-stage magnetic separation with different magnetic forces to obtain tailings and gold concentrate slurry, including: The fine particle slurry is subjected to low magnetic force primary separation by a first low magnetic force magnetic separator to obtain first tailings slurry and first slurry; The first tailings slurry is subjected to low magnetic force re-separation by a second low magnetic force magnetic separator to obtain second tailings slurry and the gold concentrate slurry; The first slurry is subjected to high magnetic force primary separation by a first high magnetic force magnetic separator to obtain third tailings slurry and the gold concentrate slurry; The third tailings slurry is subjected to high magnetic force re-separation by a second high magnetic force magnetic separator to obtain fourth tailings slurry and the gold concentrate slurry; The second tailings slurry and the fourth tailings slurry are subjected to dewatering to obtain the tailings.

8. The method of green processing of gold tailings as claimed in claim 5 wherein, The tailings after the pulp conditioning are subjected to multiple physical separations to obtain gold concentrate, further including: After the gold concentrate slurry is obtained, the gold concentrate slurry is subjected to centrifugal classification by a first cyclone to obtain third tailings slurry and classified gold concentrate slurry, and the classified gold concentrate slurry is separated into the first tailings slurry and high-concentration gold concentrate slurry.

9. The method of green processing of gold tailings as claimed in claim 8 wherein, The tailings after the pulp conditioning are subjected to multiple physical separations to obtain gold concentrate, further including: After the high-concentration gold concentrate slurry is separated, the high-concentration gold concentrate slurry is subjected to centrifugal classification by a second cyclone to obtain fourth tailings slurry and classified high-concentration gold concentrate slurry, and the classified high-concentration gold concentrate slurry is separated into the second tailings slurry and the gold concentrate.

10. The method of green processing of gold tailings as claimed in claim 9 wherein, Further including: The first tailings slurry, the second tailings slurry, the third tailings slurry and the fourth tailings slurry are collected by a tailings slurry storage tank; The tailings slurry output from the tailings slurry storage tank is subjected to solid-liquid separation by a sewage treatment device to obtain purified water, and the purified water can be recycled.

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