Cyanide-breaking and heavy-removing filling system for cyanogen-containing gold tailings

Abstract

The invention relates to the technical field of cyanogen-containing gold tailings, in particular to a cyanogen-containing gold tailing cyanogen-breaking and heavy-metal-removing filling system which comprises a tailing cyanogen-breaking and heavy-metal-removing mechanism, and the tailing cyanogen-breaking and heavy-metal-removing mechanism comprises a cyanogen-containing gold tailing slurry storage tank, a cyanogen-breaking reaction tank, a heavy metal trapping reaction tank, a cyclone, a gold concentrate tank and a tailing tank; a discharge port of the cyanogen-containing gold tailing slurry storage tank is communicated with a feed port of the cyanogen breaking reaction tank, a discharge port of the cyanogen breaking reaction tank is communicated with a feed port of the heavy metal trapping reaction tank, a discharge port of the heavy metal trapping reaction tank is communicated with a feed port of the cyclone, and a discharge port of the cyclone is respectively communicated with a feed port of the gold concentrate tank and a feed port of the tailing tank; the filling mechanism comprises a deep-cone thickener, a cement bin, a stirring assembly, a filling trailer pump and a stope; a discharging port of the tailing pond is communicated with a feeding port of the deep-cone thickener, a discharging port of the deep-cone thickener and a discharging port of the cement bin are respectively communicated with a feeding port of the stirring assembly, a discharging port of the stirring assembly is communicated with a feeding port of the filling trailer pump, and a discharging port of the filling trailer pump is communicated with a stope.

Description

Technical Field

[0001] This invention relates to the field of cyanide-containing gold tailings technology, specifically to a cyanide-containing gold tailings cyanide removal and backfilling system, and more specifically to a cyanide-containing gold tailings cyanide removal and backfilling process and an efficient intelligent mine backfilling system. Background Technology

[0002] Currently, while the industry uses cyanide ore extraction for gold ore beneficiation, it also generates and accumulates a large amount of cyanide tailings. Cyanide-containing gold tailings are solid waste generated after gold mines use the cyanide ore extraction process. They contain high concentrations of cyanide and heavy metals (such as copper, lead, and zinc). If directly stockpiled without treatment, the cyanide will pollute groundwater, soil, and the atmosphere through seepage or volatilization, seriously threatening the ecological environment and human health. According to the 2016 National Hazardous Waste List, "cyanide tailings generated during the gold ore beneficiation process using cyanide" are classified as "hazardous waste."

[0003] To facilitate the recycling of cyanide tailings and reduce their environmental harm, decyanation treatment is necessary. However, traditional treatment methods (such as alkaline chlorination and incineration) suffer from high costs, secondary pollution, and low resource utilization.

[0004] Therefore, there is still room for improvement and development in existing technologies. Summary of the Invention

[0005] To address the problems of existing technologies, this invention proposes a cyanide-containing tailings breaking, degravimetric, and backfilling system. This system can effectively treat cyanide-containing tailings slurry, improve resource utilization efficiency, reduce waste discharge rates, and achieve the goal of eliminating tailings ponds. Furthermore, it boasts high cyanide breaking efficiency, is environmentally friendly and pollution-free, and enables comprehensive utilization of cyanide-containing tailings slurry. Combined with a real-time monitoring device, it can complete backfilling operations in mining areas under various working conditions, demonstrating broad application prospects.

[0006] To achieve the above objectives, the applicable technical solution of this invention is as follows:

[0007] A cyanide-containing gold tailings decyanation and heavy metal removal backfilling system includes a tailings decyanation and heavy metal removal mechanism. The mechanism comprises a cyanide-containing gold tailings slurry storage tank, a decyanation reaction tank, a heavy metal collection reaction tank, a hydrocyclone, a gold concentrate tank, and a tailings tank. The outlet of the cyanide-containing gold tailings slurry storage tank is connected to the inlet of the decyanation reaction tank; the outlet of the decyanation reaction tank is connected to the inlet of the heavy metal collection reaction tank; and the outlet of the heavy metal collection reaction tank is connected to the inlet of the hydrocyclone. The outlet of the hydrocyclone is connected to the inlet of the gold concentrate pool and the inlet of the tailings pool, respectively; the filling mechanism includes a deep cone thickener, a cement silo, a mixing assembly, a filling trailer pump, and a stope; the outlet of the tailings pool is connected to the inlet of the deep cone thickener, the outlet of the deep cone thickener and the outlet of the cement silo are respectively connected to the inlet of the mixing assembly, the outlet of the mixing assembly is connected to the inlet of the filling trailer pump, and the outlet of the filling trailer pump is connected to the stope.

[0008] According to the above scheme, it also includes a central controller; a cyanide ion probe is installed in the cyanide breaking reaction tank; a heavy metal probe is installed in the heavy metal capture reaction tank; a lidar and a stress sensor are installed in the mining area; the cyanide ion probe, the heavy metal probe, the lidar and the stress sensor are respectively connected to the central controller for signal transmission.

[0009] According to the above scheme, an equalization tank is provided between the cyanide-containing tailings slurry storage tank and the cyanide-breaking reaction tank. The outlet of the cyanide-containing tailings slurry storage tank is connected to the inlet of the equalization tank, and the outlet of the equalization tank is connected to the inlet of the cyanide-breaking reaction tank. The inlet of the equalization tank is also connected to a concentrated sulfuric acid storage tank.

[0010] According to the above scheme, the cyanide-breaking reaction tank includes a primary cyanide-breaking reaction tank and a secondary cyanide-breaking reaction tank. The outlet of the regulating tank is connected to the inlet of the primary cyanide-breaking reaction tank, and the outlet of the primary cyanide-breaking reaction tank is connected to the inlet of the secondary cyanide-breaking reaction tank.

[0011] According to the above scheme, the inlet of the primary cyanide-removing reaction tank is also connected to a cyanide removal agent storage tank; the inlet of the secondary cyanide-removing reaction tank is also connected to a cyanide removal agent storage tank.

[0012] According to the above scheme, the inlet of the heavy metal capture reaction tank is also connected to a flocculant storage tank and a chelating agent storage tank.

[0013] According to the above scheme, the feed inlet of the hydrocyclone is also connected to a flotation agent storage tank.

[0014] According to the above scheme, a shaking table is provided between the gold concentrate pool and the hydrocyclone; a flotation column is provided between the tailings pool and the hydrocyclone.

[0015] According to the above scheme, the mixing assembly includes a mixer and a mixing tank. The discharge port of the deep cone thickener is connected to a sedimentation tank and a buffer silo. The discharge ports of the sedimentation tank, the buffer silo, and the cement silo are respectively connected to the inlet of the mixer. The discharge port of the mixer is connected to the inlet of the mixing tank. The discharge port of the mixing tank is connected to the inlet of the filling trailer pump.

[0016] According to the above scheme, the lidar is deployed in a grid pattern on the top plate of the mining area; the stress sensor is arranged in a diamond array on the bottom plate of the mining area.

[0017] Beneficial effects of this invention:

[0018] This invention, with its specific design, can effectively treat cyanide-containing tailings slurry, improve resource utilization efficiency, reduce waste discharge rate, and achieve the goal of eliminating tailings ponds. Furthermore, it boasts high cyanide breaking efficiency, is environmentally friendly and pollution-free, and enables comprehensive utilization of cyanide-containing tailings slurry. Combined with a real-time monitoring device, it can complete mining backfilling operations under various working conditions, demonstrating broad application prospects. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the cyanide-containing gold tailings breaking, cyanide removal, and backfilling system of the present invention;

[0020] Figure 2 This is a schematic diagram of the structure of the gold mine tailings classification, cyanide removal, and heavy metal removal module of the present invention.

[0021] Figure 3 This is a schematic diagram of the structure of the resource recycling module of the present invention;

[0022] Figure 4 This is a schematic diagram of the filling material preparation part of the present invention;

[0023] Figure 5 This is a schematic diagram of the structure of the field lidar and stress sensor of the present invention.

[0024] Figure 6 This is a schematic diagram of the process flow of the present invention;

[0025] Figure 7 This is a schematic diagram of the dynamic control logic of the present invention.

[0026] In the picture:

[0027] 1. Cyanide-containing tailings slurry storage tank; 2. Concentrated sulfuric acid storage tank; 3. Cyanide removal agent storage tank 1; 4. Cyanide removal agent storage tank 2; 5. Flocculant storage tank; 6. Flotation agent storage tank; 7. Adjustment tank; 8. Primary cyanide-breaking reaction tank; 9. Secondary cyanide-breaking reaction tank; 10. Heavy metal capture reaction tank; 11. Hydrocyclone; 12. Shaking table; 13. Gold concentrate pond; 14. Flotation column; 15. Tailings pond; 16. Cyanide ion probe; 17. Heavy metal probe; 18. Deep cone thickener; 19. Sedimentation tank; 20. Buffer tank; 21. Cement silo; 22. Mixer; 23. Mixing tank; 24. Filling trailer pump; 25. Stope; 26. LiDAR; 27. Stress sensor; 28. Central controller; 29. ​​Chelating agent storage tank. Detailed Implementation

[0028] The technical solution of the present invention will be described below with reference to the accompanying drawings and embodiments.

[0029] like Figures 1 to 7As shown, the present invention discloses a cyanide-containing tailings cyanide-removal and heavy metal-reduction backfilling system, comprising a tailings cyanide-removal and heavy metal-reduction mechanism. This mechanism includes a cyanide-containing tailings slurry storage tank 1, a cyanide-removal reaction tank, a heavy metal collection reaction tank 10, a hydrocyclone 11, a gold concentrate tank 13, and a tailings tank 15. The outlet of the cyanide-containing tailings slurry storage tank 1 is connected to the inlet of the cyanide-removal reaction tank, the outlet of the cyanide-removal reaction tank is connected to the inlet of the heavy metal collection reaction tank 10, and the outlet of the heavy metal collection reaction tank 10 is connected to the inlet of the hydrocyclone 11. The outlet of the flow device 11 is connected to the inlet of the gold concentrate pool 13 and the inlet of the tailings pool 15, respectively; the filling mechanism includes a deep cone thickener 18, a cement silo 21, a mixing assembly, a filling trailer pump 24, and a stope 25; the outlet of the tailings pool 15 is connected to the inlet of the deep cone thickener 18, the outlet of the deep cone thickener 18 and the outlet of the cement silo 21 are respectively connected to the inlet of the mixing assembly, the outlet of the mixing assembly is connected to the inlet of the filling trailer pump 24, and the outlet of the filling trailer pump 24 is connected to the stope 25. This setup effectively removes cyanide and heavy metals from the cyanide-containing tailings slurry transported from the cyanide-containing tailings slurry storage tank 1 via the cyanide-removing reaction tank and heavy metal capture reaction tank 10. The resulting gold concentrate is stored in the gold concentrate tank 13, and the tailings are stored in the tailings tank 15. The tailings in the tailings tank 15 are processed by the deep cone thickener 18 to obtain backfill material tailings (the tailings are reused as backfill material, reducing mine backfill costs) and liquid, which are then mixed with cement silo 2. 1. The backfill material, tailings, liquid, and cement are mixed according to the required proportions using a mixing assembly to produce a high-quality backfill slurry. Finally, the backfill pump 24 is used to backfill the stope 25. This method can effectively treat cyanide-containing tailings slurry, improve resource utilization efficiency, reduce waste discharge rate, and achieve the goal of eliminating tailings ponds. It also has high cyanide breaking efficiency, is environmentally friendly and pollution-free, and can realize the comprehensive utilization of cyanide-containing tailings slurry. With the help of a real-time monitor, it can complete backfilling operations in various working conditions and has broad application prospects.

[0030] Furthermore, it also includes a central controller 28; a cyanide ion probe 16 is installed in the cyanide-breaking reaction tank; a heavy metal probe 17 is installed in the heavy metal capture reaction tank 10; a lidar 26 and a stress sensor 27 are installed in the stope 25; the cyanide ion probe 16, the heavy metal probe 17, the lidar 26, and the stress sensor 27 are respectively connected to the central controller 28 for signal transmission. With this configuration, the cyanide ion probe 16 can monitor the cyanide ion concentration in the tailings slurry in the cyanide-breaking reaction tank in real time, and feed this information back to the central controller 28 as an input; the heavy metal probe 17 can monitor the heavy metal ion concentration in the tailings slurry in real time, and feed this information back to the central controller 28 as an input; the lidar 26 and the stress sensor 27 can monitor the conditions of the stope 25 in real time, and feed this information back to the central controller 28 as input.

[0031] Preferably, the central controller 28 integrates multi-source sensor data to achieve cyanide-breaking and filling interlocking control through sensor data closed-loop. The cyanide-breaking reaction process is tracked in real time via the cyanide ion probe 16 and the heavy metal sensor 17. Based on the collaborative analysis of the three-dimensional scanning of the lidar 26 and the array of stress sensors 27, a dynamic mapping mechanism of the filling requirements and proportioning parameters of the stope 25 is established, and the cement addition amount is dynamically calculated based on the cavity volume scanned in real time by the lidar 26.

[0032] Preferably, the cyanide ion probe 16 is embedded in the inner wall of the cyanide breaking reaction tank at a height of 1 / 3 from the bottom of the tank; the heavy metal probe 17 is installed in the overflow trough of the heavy metal capture reaction tank 10.

[0033] Furthermore, an equalization tank 7 is provided between the cyanide-containing tailings slurry storage tank 1 and the cyanide-breaking reaction tank. The outlet of the cyanide-containing tailings slurry storage tank 1 is connected to the inlet of the equalization tank 7, and the outlet of the equalization tank 7 is connected to the inlet of the cyanide-breaking reaction tank. The inlet of the equalization tank 7 is also connected to a concentrated sulfuric acid storage tank 2. With this configuration, concentrated sulfuric acid is supplied to the equalization tank 7 through the concentrated sulfuric acid storage tank 2 to adjust the pH value of the tailings slurry.

[0034] Preferably, the size of the equalization tank 7 is 3m×3m×2m, and a stirring rod is installed in the tank. The reaction time for adjusting the pH is 15min; the concentration of concentrated sulfuric acid is 98%.

[0035] Furthermore, the cyanide-removing reaction tank includes a primary cyanide-removing reaction tank 8 and a secondary cyanide-removing reaction tank 9. The outlet of the regulating tank 7 is connected to the inlet of the primary cyanide-removing reaction tank 8, and the outlet of the primary cyanide-removing reaction tank 8 is connected to the inlet of the secondary cyanide-removing reaction tank 9. The inlet of the primary cyanide-removing reaction tank 8 is also connected to a first cyanide removal agent storage tank 3; the inlet of the secondary cyanide-removing reaction tank 9 is also connected to a second cyanide removal agent storage tank 4. This configuration allows first cyanide removal agent to be supplied to the primary cyanide-removing reaction tank 8 via the first cyanide removal agent storage tank 3, and second cyanide removal agent to be supplied to the secondary cyanide-removing reaction tank 9 via the second cyanide removal agent storage tank 4.

[0036] Among them, the cyanide ion probes 16 in the primary cyanide-breaking reaction tank 8 and the secondary cyanide-breaking reaction tank 9 can monitor the cyanide ion concentration in the tailings slurry in real time, and feed it back to the central controller 28 as an input to adjust the size of the discharge port of the first cyanide removal agent storage tank 3 and the second cyanide removal agent storage tank 4.

[0037] Preferably, the size of the primary cyanide-removing reaction tank 8 is 4m×4.5m×2m. A stirring rod is installed in the tank, and the reaction is carried out under stirring conditions for 30-60 minutes to obtain pre-cyanide-removed tailings slurry. The stirring method adopts segmented stirring intensity control: in the initial stage (0-15min), high-intensity stirring (300r / min) is used to promote the rapid mixing of free cyanide (CN-) and cyanide removal agent 1. In the later stage (15-60min), the stirring intensity is reduced to medium and low intensity (150-200r / min) to reduce reagent consumption, which can reduce the dosage of cyanide removal agent 1 by 1-2%. The dosage of cyanide removal agent 1 is 1% to 2.5%, and its main function is to decompose free cyanide (CN-).

[0038] Preferably, the secondary cyanide-removing reaction tank 9 has a size of 4m × 4.5m × 2m. A stirring rod is installed inside the tank, and the reaction proceeds for 30-60 minutes under stirring conditions to obtain cyanide-removed tailings slurry. The stirring method employs temperature-assisted control: to address the recalcitrant degradation of complexed cyanides (such as [Cu(CN)4]2-), the reaction temperature is increased from room temperature to 35-40℃ (achieved through industrial waste heat or a low-power heating system), which shortens the reaction time to 35-40 minutes and simultaneously improves the utilization rate of the cyanide removal agent. The dosage of the cyanide removal agent is 0.3%–1%, and its main function is to treat complexed cyanides (such as [Cu(CN)4]2-).

[0039] Preferably, the reaction time of the primary cyanide breaking reaction tank 8 and the secondary cyanide breaking reaction tank 9 is dynamically controlled. When the cyanide ion probe 16 detects a free cyanide concentration of <5mg / L, the reaction time is shortened to 30-40min; when the complexed cyanide concentration is >1mg / L, the reaction time is extended to 50-60min.

[0040] Furthermore, the inlet of the heavy metal capture reaction tank 10 is also connected to a flocculant storage tank 5 and a chelating agent storage tank 29. This configuration allows flocculant and chelating agent to be supplied into the heavy metal capture reaction tank 10 via the flocculant storage tank 5 and the chelating agent storage tank 29.

[0041] The heavy metal probe 17 in the heavy metal capture reaction tank 10 can monitor the concentration of heavy metal ions in the tailings slurry in real time and feed it back to the central controller 28 as an input to adjust the size of the outlet of the flocculant storage tank 5.

[0042] Preferably, the heavy metal capture reaction tank 10 has a size of 4m × 4.5m × 2m. A stirring rod is installed inside the tank, and a chelation-flocculation staged treatment is implemented to enhance the targeted removal of heavy metals. First, a heavy metal chelating agent (such as dithiocarbamate) is added, and after reacting for 10 minutes, polyacrylamide (CPAM) flocculant is added. The process is then switched to a gradient stirring mode: first, the flocculant is rapidly stirred at 200 rpm for 2 minutes to disperse it, then the speed is reduced to 40 rpm for 15 minutes to promote floc growth. The pH is controlled and adjusted in stages, and the reaction is continued for 20 minutes under stirring conditions to remove heavy metals. The residual heavy metals in the tailings after treatment meet the following criteria: [Cu2+] + [Pb2+] < 0.05 mg / L, [CN-] < 0.5 mg / L, and the 28-day compressive strength of the filling body is ≥ 8 MPa. Preferably, the chelating agent contains a dithiocarbamate group with the general structural formula: R1R2N-CS2M, where R1 and R2 are C1-C6 alkyl groups, and M is Na. + / K+; wherein, during the chelation stage, the pH is controlled at 8.0-9.0, the stirring speed is 50-120 rpm, and the reaction time is 10-20 min; during the flocculation stage, the stirring speed is first 180-220 rpm for 1-3 min, and then 30-50 rpm for 10-20 min; the flocculant is polyacrylamide, the pH is controlled at 8-9, and the reaction time is 20 min.

[0043] Furthermore, the feed inlet of the hydrocyclone 11 is also connected to a flotation reagent storage tank 6; a shaking table 12 is provided between the gold concentrate pool 13 and the hydrocyclone 11; and a flotation column 14 is provided between the tailings pool 15 and the hydrocyclone 11. This arrangement allows flotation reagent to be supplied to the hydrocyclone 11 via the flotation reagent storage tank 6.

[0044] Preferably, the hydrocyclone 11 dynamically matches the tailings particle size distribution (-38μm accounts for 74.84%), with an adjustment range of 20-50μm; the shaking table 12 adopts the LY mineral processing shaking table, with parameters adaptively adjusted based on tailings characteristics; the flotation column 14 consists of a column body, a bubble generator, a foam layer spraying system, etc., with a column height of up to 6-8 meters, and an external bubble generator is used to reduce clogging.

[0045] Preferably, the flotation agent is 50 g / t of butyl xanthate and 15 g / t of pine oil.

[0046] Furthermore, the mixing assembly includes a mixer 22 and a mixing tank 23. The discharge port of the deep cone thickener 18 is connected to a sedimentation tank 19 and a buffer chamber 20. The discharge ports of the sedimentation tank 19, the buffer chamber 20, and the cement silo 21 are respectively connected to the inlet of the mixer 22. The discharge port of the mixer 22 is connected to the inlet of the mixing tank 23, and the discharge port of the mixing tank 23 is connected to the inlet of the filling pump 24. With this configuration, the mixing tank 22 mixes the tailings, liquid, and cement of the filling material to produce a high-quality filling slurry, which is then transported to the filling pump 24 via the mixing tank 23.

[0047] The sedimentation tank 19 is used for buffering liquids, and the buffer tank 20 is used for buffering tailings of the filling material; the discharge port of the cement silo 21 is equipped with a discharge valve.

[0048] Furthermore, the lidar 26 is arranged in a grid pattern on the top plate of the stope 25; the stress sensors 27 are arranged in a diamond array on the bottom plate of the stope 25. This configuration, through the coordinated sensing of the grid-like lidar 26 and the diamond array of stress sensors 27, enables dynamic assessment of the structural stability of the stope 25, improving the response and reagent prediction accuracy of the stope 25.

[0049] Preferably, the lidar 26 is deployed on the roof of the mining area 25 in a 5m×5m grid pattern.

[0050] Preferably, for the filling sequence of different areas of the stope 25, a segmented solidification control is adopted: an early strength agent (such as calcium chloride, dosage 2-3%) is added to the slurry in the high stress zone to accelerate solidification, and a retarder (such as sucrose, dosage 0.5-1%) is added to the closed zone to extend the transportable time and improve the overall stability of the filling body; wherein, in the segmented solidification control, the early strength agent is calcium chloride (dosage 2-3%), and the retarder is sucrose (dosage 0.5-1%).

[0051] Preferably, the central controller 28 dynamically calculates the amount of cement to be added based on the cavity volume scanned in real time by the lidar 26, according to the formula: cement amount (kg) = cavity volume (m3) × regional strength coefficient K. The value of K is calculated based on the real-time data of the stress sensor 27 through the stress-strength mapping function. In the load-bearing area, K = 1.2, and in the closed area, K = 0.8.

[0052] The central controller 28 can also be used to control the size of the cyanide-containing tailings slurry storage tank 1, concentrated sulfuric acid storage tank 2, cyanide removal agent storage tank 3, cyanide removal agent storage tank 4, flocculant storage tank 5, flotation agent storage tank 6, and the discharge port of cement silo 21.

[0053] Experimental Example 1:

[0054] Chelation-flocculation operation process:

[0055] (1) Take 10 kg of diethylenetriamine (DETA), 8 kg of carbon disulfide, and 15 L of NaOH solution (30 wt%). Stir in a reactor at 60 °C for 2 h to generate dithiocarbamate chelating agent HMCA. Cool to 25 °C for later use.

[0056] (2) Dynamically adjust the dosage of chelating agent based on real-time data from heavy metal sensor 17: when [Cu 2+ When [Cu] > 50 mg / L, the dosage is 0.8-1.2 wt% of the tailings slurry volume; when [Cu] 2 When the concentration of [+] is less than 50 mg / L, the dosage should be reduced to 0.3-0.5 wt%.

[0057] (3) Chelation stage: Adjust the pH to 8.5±0.3 with NaOH solution to promote the ionization of sulfur atoms; Flocculation stage: Add dilute H2SO4 to adjust the pH to 7.0±0.5 before adding flocculant to avoid hydrolysis of CPAM under alkaline conditions;

[0058] (4) The stirring shaft of the heavy metal capture reaction tank is used for heat conduction to maintain the slurry temperature at 35-40℃, thereby increasing the chelation reaction rate by 2 times.

[0059] (5) After the chelated flocculent sludge is filtered by pressure, the filter cake is desorbed with 5wt% H2SO4, and the desorbed liquid is electrolyzed to recover metallic copper (purity >99.5%). The residue is used as backfill aggregate.

[0060] Take 1m of cyanide tailings slurry from a gold mine 3 (containing Cu) 2+ (85 mg / L, Pb2+ 42 mg / L, CN- 596 mg / L), treated with the following methods respectively:

[0061] Scheme A (the present invention): First, add dithiocarbamate chelating agent (0.5wt%), pH=8.5, and stir slowly for 15min; then add CPAM flocculant (0.1wt%), stir in a gradient and let it settle.

[0062] Option B (conventional flocculation): Direct addition of PAC-PAM composite flocculant (0.8 wt%); Results: Option A had a better effect on Cu2+. + / Pb 2+ The removal rate reached 99.2%, and the sludge volume was reduced by 40%; the removal rate of Option B was only 78.5%.

[0063] Studies have shown that after treatment with dithiocarbamate, the Zeta potential of tailings particles increased from -32 mV to -5 mV, indicating that chelates were deposited on the particle surface; the potential reversed to +15 mV after the addition of CPAM, confirming the charge neutralization effect. Combined with scanning electron microscopy, the flocs formed by traditional flocculants are loose networks (pore size > 5 μm), while the chelated flocs of this invention are dense clusters (pore size < 1 μm), confirming that heavy metals are encapsulated within the flocs.

[0064] The chelated flocculant sludge was desorbed in 0.1M HCl for 30 minutes. The recovered chelating agent was reused 5 times for Cu2+. + The removal rate remained above 90%, confirming its renewability. The treated tailings were tested according to GB5085.3, and the Cu content in the leachate was <0.05 mg / L, meeting the requirements of the "Comprehensive Treatment Implementation Plan for Heavy Metal Pollution".

[0065] Experimental Example 2:

[0066] A tailings slurry from a certain mine was selected, and its wastewater was quantitatively analyzed. The results were as follows: the cyanide-containing comprehensive tailings slurry had a pH of 9.3, a total cyanide content of 596.57 mg / L, and a solid content of 42%; the cyanide-containing single tailings slurry had a pH of 11.1, a total cyanide content of 134.92 mg / L, and a solid content of 42%.

[0067] According to the GB8978-1996 (Grade I) standard for integrated wastewater discharge, the pH is 6-9 and the total cyanide is 0.5 mg / L.

[0068] The proportion of particles smaller than 74 μm (-200 mesh) in the whole tailings sample was approximately 86.84%, and the proportion of particles smaller than 38 μm (-400 mesh) was approximately 74.84%.

[0069] Studies have shown that in order to ensure that the filling material does not separate into layers and form a so-called "structured flow" during long-term transportation in pipelines, the proportion of tailings with a particle size of -38μm must be greater than 20%. Therefore, using tailings as aggregate can ensure the long-distance transportation of filling slurry.

[0070] For cyanide removal in tailings slurry, control the pH within a suitable range, adjust the acidity and react for 15 minutes, add 1.5% cyanide removal agent 01, react for 45 minutes, adjust the pH, add 0.6% cyanide removal agent 02 for secondary cyanide removal, stir and react for 45 minutes, add polyacrylamide, flocculate, and the total cyanide in the effluent can stably meet the integrated wastewater discharge standard (Grade I).

[0071] The tailings slurry from the cyanide crushing process is processed through a deep cone thickener to obtain the tailings and liquid for the filling body. Based on the BIM model, the strength level of the filling area is divided, and the mixing ratio instructions are dynamically output to the mixer: when the area is detected as a load-bearing area (compressive strength requirement ≥8MPa), the tailings:cement:water ratio of 6:1:2.5 is automatically executed; when the area is detected as a closed area (density needs to be reduced), the ratio of tailings:cement:foaming agent of 8:1.5:0.3 is switched.

[0072] The filling operation is completed using a filling pump, and combined with lidar and stress sensors, the deformation data of the filling body is collected in real time, thereby intelligently adjusting the size of each feed port.

[0073] A comparative test was conducted with traditional processes, and the results are shown in the table below (Note: Strength testing standard GB / T 50081, cost accounting includes reagents and energy consumption):

[0074]

[0075] X-ray diffraction (XRD) analysis of the tailings after cyanide removal showed that the residual heavy metal content was less than 0.03 ppm (detection standard: EPA6010D); CT scan of the backfill showed that the density gradient distribution of the load-bearing area / closed area conformed to the BIM model prediction (error <3%).

[0076] In this example, the K value (1.2 / 0.8) was obtained by fitting 200 sets of stope pressure tests, and the fitting formula is as follows:

[0077] K = 0.6 × ln(stress value in MPa) + 0.8 (R² = 0.93)

[0078] The fitting formula was obtained through 200 sets of mining pressure tests (R2 = 0.93). When the stress value is 5 MPa, K = 1.2, and when the stress value is 2 MPa, K = 0.8.

[0079] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other modifications under the guidance of the present invention without departing from the spirit and scope of the claims. All of these modifications are within the scope of protection of the present invention.

Claims

1. A system for breaking down and removing cyanide from gold-containing tailings and filling them with wastewater, characterized in that, include: The tailings cyanide and heavy metal removal mechanism includes a cyanide-containing gold tailings slurry storage tank (1), a cyanide-breaking reaction tank, a heavy metal collection reaction tank (10), a hydrocyclone (11), a gold concentrate tank (13), and a tailings tank (15). The outlet of the cyanide-containing gold tailings slurry storage tank (1) is connected to the inlet of the cyanide-breaking reaction tank, the outlet of the cyanide-breaking reaction tank is connected to the inlet of the heavy metal collection reaction tank (10), the outlet of the heavy metal collection reaction tank (10) is connected to the inlet of the hydrocyclone (11), and the outlet of the hydrocyclone (11) is connected to the inlet of the gold concentrate tank (13) and the inlet of the tailings tank (15), respectively. The filling mechanism includes a deep cone thickener (18), a cement silo (21), a mixing assembly, a filling trailer pump (24), and a stope (25); the outlet of the tailings pond (15) is connected to the inlet of the deep cone thickener (18), the outlet of the deep cone thickener (18) and the outlet of the cement silo (21) are respectively connected to the inlet of the mixing assembly, the outlet of the mixing assembly is connected to the inlet of the filling trailer pump (24), and the outlet of the filling trailer pump (24) is connected to the stope (25).

2. The cyanide-containing gold tailings demineralization, cyanide removal, and backfilling system according to claim 1, characterized in that: It also includes a central controller (28); a cyanide ion probe (16) is provided in the cyanide breaking reaction tank; a heavy metal probe (17) is provided in the heavy metal capture reaction tank (10); a lidar (26) and a stress sensor (27) are provided in the mining area (25); the cyanide ion probe (16), the heavy metal probe (17), the lidar (26) and the stress sensor (27) are respectively connected to the central controller (28) for signal transmission.

3. The cyanide-containing gold tailings demineralization, cyanide removal, and backfilling system according to claim 2, characterized in that: A regulating tank (7) is provided between the cyanide-containing tailings slurry storage tank (1) and the cyanide-breaking reaction tank. The outlet of the cyanide-containing tailings slurry storage tank (1) is connected to the inlet of the regulating tank (7), and the outlet of the regulating tank (7) is connected to the inlet of the cyanide-breaking reaction tank. The inlet of the regulating tank (7) is also connected to a concentrated sulfuric acid storage tank (2).

4. The cyanide-containing gold tailings blasting, decyanation, and backfilling system according to claim 3, characterized in that: The cyanide-breaking reaction tank includes a primary cyanide-breaking reaction tank (8) and a secondary cyanide-breaking reaction tank (9). The outlet of the regulating tank (7) is connected to the inlet of the primary cyanide-breaking reaction tank (8), and the outlet of the primary cyanide-breaking reaction tank (8) is connected to the inlet of the secondary cyanide-breaking reaction tank (9).

5. A cyanide-containing gold tailings breaking, decyanation, and backfilling system according to claim 4, characterized in that: The inlet of the primary cyanide-removing reaction tank (8) is also connected to a cyanide removal agent storage tank (3); the inlet of the secondary cyanide-removing reaction tank (9) is also connected to a cyanide removal agent storage tank (4).

6. A cyanide-containing gold tailings ore breaking, decyanation, and backfilling system according to claim 2, characterized in that: The inlet of the heavy metal capture reaction tank (10) is also connected to a flocculant storage tank (5) and a chelating agent storage tank (29).

7. A cyanide-containing gold tailings ore breaking, decyanation, and backfilling system according to claim 2, characterized in that: The feed inlet of the hydrocyclone (11) is also connected to a flotation agent storage tank (6).

8. A cyanide-containing gold tailings ore breaking, decyanation, and backfilling system according to claim 2, characterized in that: A shaking table (12) is provided between the gold concentrate pool (13) and the hydrocyclone (11); a flotation column (14) is provided between the tailings pool (15) and the hydrocyclone (11).

9. A cyanide-containing gold tailings ore breaking, decyanation, and backfilling system according to claim 2, characterized in that: The mixing assembly includes a mixer (22) and a mixing tank (23). The outlet of the deep cone thickener (18) is connected to a sedimentation tank (19) and a buffer chamber (20). The outlets of the sedimentation tank (19), the buffer chamber (20), and the cement silo (21) are respectively connected to the inlet of the mixer (22). The outlet of the mixer (22) is connected to the inlet of the mixing tank (23). The outlet of the mixing tank (23) is connected to the inlet of the filling trailer pump (24).

10. A cyanide-containing gold tailings ore breaking, decyanation, and backfilling system according to claim 2, characterized in that: The lidar (26) is arranged in a grid on the top plate of the mining area (25); the stress sensor (27) is arranged in a diamond array on the bottom plate of the mining area (25).

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