A stabilizer for controlling heavy metal pollution of copper mine beneficiation tailings

Abstract

The present application relates to a kind of stabilizer for controlling copper ore dressing tailings heavy metal pollution, can effectively solve the problem of copper ore dressing tailings heavy metal pollution.Stabilizer composition includes: basic component A and reinforcing component B;Wherein basic component A is polyaluminum ferric chloride 35%~50%, polyferric sulfate 5%~10%, calcium hydroxide 20%~50%, calcium carbonate 10%~30%, iron oxide 0.1%~2.0%;Reinforcing component B is sodium silicate.Polyaluminum ferric chloride, polyferric sulfate, calcium hydroxide, calcium carbonate, iron oxide are mixed uniformly, activated, i.e.the basic component A;Reinforcing component B is made into 0.1~3.0% aqueous solution and used.The raw material of the present application is rich, low cost, can realize the solidification and stabilization of heavy metal pollutants in copper ore tailings containing copper, lead, zinc, cadmium, arsenic and other heavy metal pollutants, prevent the diffusion of residual heavy metal pollutants in copper tailings from polluting soil, groundwater and surface water.

Description

Technical Field

[0001] This invention relates to the field of tailings management technology, and more specifically to a stabilizer for controlling heavy metal pollution in copper ore beneficiation tailings. Background Technology

[0002] Due to the continuous changes in mineralization and geological conditions, copper ore is usually associated with small amounts of metallic sulfide minerals such as galena, sphalerite, pyrite (FeS2), and arsenopyrite (FeAsS), as well as the oxidation products of these minerals. The large amount of tailings generated during copper mining and beneficiation, in terms of solubility, includes water-soluble heavy metal sulfates and sulfites, water-soluble heavy metal oxides in acidic water, and water-insoluble heavy metal sulfide minerals. Due to the presence of various heavy metal minerals remaining in the tailings, the combined effects of water and oxygen, especially acid rain erosion, during storage lead to the oxidation of these minerals, generating various water-soluble heavy metal substances. Simultaneously, the oxidation of metal sulfides such as pyrite (FeS2) and arsenopyrite (FeAsS) in the tailings produces acidic substances, further acidifying the microenvironment within the tailings and exacerbating the leaching of heavy metals. It can be seen that after soaking in water, heavy metals in copper ore tailings will transfer to the aqueous phase, and the concentration can exceed the limits of the "Integrated Wastewater Discharge Standard" (GB8978-1996), typically classifying them as Class II solid waste, causing serious heavy metal pollution to the ecological environment. Controlling heavy metal pollution in copper ore tailings and achieving the harmless disposal of copper ore tailings has become a major environmental and social problem that urgently needs to be solved in the copper mining and beneficiation industry. Summary of the Invention

[0003] The technical problem this invention aims to solve is to provide a stabilizer for controlling heavy metal pollution in copper mine tailings, capable of harmlessly disposing of copper mine tailings containing heavy metal pollutants such as arsenic, cadmium, lead, zinc, and copper. This patent enables the solidification and stabilization of heavy metal pollutants in copper mine tailings, completely eliminating and eradicating the pollution hazards and potential risks associated with copper mine tailings.

[0004] To solve this technical problem, the present invention adopts the following technical solution:

[0005] A stabilizer for controlling heavy metal pollution in copper ore beneficiation tailings, comprising: a base component A and an enhancing component B;

[0006] The basic component A includes polyaluminum ferric chloride, polyferric sulfate, calcium hydroxide, calcium carbonate, and iron oxide;

[0007] The polyaluminum ferric chloride is an industrial-grade product, with the main components being alumina ≥26%, ferric oxide 3%–6%, basicity ≥65%, and arsenic ≤0.0003%.

[0008] The calcium hydroxide, polyferric sulfate, calcium carbonate, and iron oxide mentioned are all industrial-grade products;

[0009] Preferably, calcium hydroxide, polyferric sulfate, calcium carbonate, and iron oxide are analytical grade products.

[0010] Based on a total mass of 100%, the basic component A comprises: 35%–50% polyaluminum ferric chloride, 5%–10% polyferric sulfate, 20%–50% calcium hydroxide, 10%–30% calcium carbonate, and 0.1%–2.0% iron oxide;

[0011] Preferably, the basic component A is: 49% polyaluminum ferric chloride, 10% polyferric sulfate, 30% calcium hydroxide, 10% calcium carbonate, and 1% iron oxide;

[0012] The preparation method of the basic component A involves mixing polyaluminum ferric chloride, polyferric sulfate, calcium hydroxide, calcium carbonate, and iron oxide in a certain proportion.

[0013] Preferably, the preparation method of the basic component A involves mixing polyaluminum ferric chloride, polyferric sulfate, calcium hydroxide, calcium carbonate, and iron oxide in a certain proportion and then activating them.

[0014] The activation refers to grinding a mixture of polyaluminum ferric chloride, polyferric sulfate, calcium hydroxide, calcium carbonate, and iron oxide powder in a grinding device.

[0015] The grinding equipment mentioned refers to ball mills, Raymond mills, etc.;

[0016] Preferably, the material is ground to a fineness of ≤200 mesh;

[0017] The reinforcing component B is: industrial-grade sodium silicate, prepared as an aqueous solution for use;

[0018] Preferably, the reinforcing component B is: analytical grade sodium silicate, prepared using distilled water;

[0019] This invention also provides a method for applying the stabilizer described above to control heavy metal pollution in copper ore beneficiation tailings.

[0020] Preferably, the copper mine tailings contain at least one of the heavy metals arsenic, cadmium, lead, zinc, and copper, wherein the content of arsenic in the tailings is ≤5000 mg / kg, the content of lead is ≤5000 mg / kg, the content of zinc is ≤5000 mg / kg, and the content of copper is ≤1000 mg / kg.

[0021] This invention also provides a method for controlling heavy metal pollution in copper ore beneficiation tailings, comprising the following steps:

[0022] Step 1: Mix the basic component A with copper ore tailings at a mass ratio of 0.5% to 3%;

[0023] Step 2: Prepare an aqueous solution of reinforcing component B with a concentration of 0.1~3.0% and add it to the copper ore tailings that have been mixed in Step 1 to form a solidified and stabilized body with a water content of 20%~40%.

[0024] Step 3: Stack the solidified and stabilized body obtained in Step 2 to form a copper ore tailings solidified body;

[0025] Step 4: The solidified body is cured to complete the solidification and stabilization of heavy metal pollutants in copper mine tailings.

[0026] Preferably, in step two, the concentration of the aqueous solution is 0.2% and the water content is 25%.

[0027] Preferably, the pH of the cured and stabilized body in step two is controlled at 7.5~9 by controlling the amount of basic component A in step one;

[0028] Preferably, in step four, the curing time is 1 to 2 days.

[0029] Beneficial effects

[0030] The main advantages of this invention compared to existing technologies are:

[0031] Copper ore tailings typically have a particle size of around 200 mesh. Heavy metals such as arsenic, cadmium, lead, zinc, and copper in the tailings exist in two phases based on their solubility: one is water-soluble substances containing one or more of these heavy metals; the other is water-insoluble sulfide minerals or oxides containing these heavy metals. The latter type of sulfide minerals, under the presence of water and oxygen, are easily oxidized to form water-soluble substances, acidifying the tailings microenvironment and further dissolving heavy metal oxides, thus causing heavy metal pollution from copper ore tailings. This invention can control heavy metal pollution from tailings from multiple dimensions. The polyaluminum ferric chloride, polyferric sulfate, calcium hydroxide, calcium carbonate, and iron oxide used in this invention, after being compounded and mechanically ground to ≤200 mesh, exhibit altered physicochemical properties. Extensive data shows that the finer the particle size, the larger the specific surface area and the greater the surface free energy. When the stabilizer is smaller than 200 mesh, and the copper ore tailings contain at least one of the heavy metals arsenic, cadmium, lead, zinc, and copper, with the arsenic content ≤5000 mg / kg, lead content ≤5000 mg / kg, zinc content ≤5000 mg / kg, and copper content ≤1000 mg / kg, the stabilizer can better mix thoroughly with the equally fine tailings and distribute evenly among various minerals. Under the action of the reinforcing components and water, the stabilizer first undergoes a hydrolysis reaction and immediately reacts with heavy metals such as cadmium, arsenic, zinc, lead, and copper in a series of chemical reactions. XRD tests show that it reacts with cadmium to form Cd4Al2O6Cl2·10H2O, with arsenic to form Al2(AsO4)(OH)3·3H2O, and with zinc to form Zn5(OH)8Cl2·H2O, etc. (see...) Figure 2 , Figure 3 , Figure 4 Example); Simultaneously, complex physicochemical mineralization processes such as agglomeration, polymerization, adsorption, and bridging occur. Referring to the EDS test results of stabilized lead-zinc mine tailings, heavy metals such as arsenic, copper, and lead react with iron and aluminum hydrolyzed micelles in the stabilizer to form polynuclear complexes, which are then solidified together. Figure 5 (Example) This invention significantly reduces the toxicity and leaching rate of heavy metals. Sodium silicate is used as a reinforcing agent, working synergistically with basic component A to stabilize the heavy metal minerals generated during the solidification process. The toxicity of the leached heavy metal pollutants from the stabilized copper ore tailings is far below the limits set by the "Integrated Wastewater Discharge Standard" (GB8978-1996). After stabilization, the copper ore tailings are transformed from Class II solid waste to Class I solid waste. Furthermore, the concentration of heavy metal pollutants in the leachate is below the Class III surface water standard limit, indicating a very low environmental pollution risk. Therefore, the copper ore tailings heavy metal stabilizer of this invention is a fast-acting and effective heavy metal solidification and stabilization agent.

[0032] The calcium carbonate and iron oxide in the stabilizer for controlling heavy metal pollution in copper ore beneficiation tailings provided by this invention are poorly soluble in water, but can react with acid in acidic aqueous solutions. The acid produced by the oxidation of sulfide minerals in the tailings is immediately neutralized by calcium carbonate and iron oxide, preventing further oxidation and precipitation of various heavy metal minerals in the tailings. This stabilizer has strong resistance to acid rain and acidification by sulfide minerals. Therefore, the copper ore beneficiation tailings heavy metal stabilizer of this invention also has the function of stabilizing the pH of the solidified tailings. The solidified and stabilized tailings have good weather resistance and can effectively and stably reduce the leaching of heavy metal pollutants in copper ore beneficiation tailings for a long time. As can be seen from the results in the examples (Table 1), after 300 days of open-air storage, the leaching toxicity remains unchanged and is still very low. The amount of stabilizer used by weight is only 0.5% to 3% of the copper ore beneficiation tailings, which is small and results in minimal increase in the volume of the treated tailings. It can simultaneously solidify and stabilize heavy metals cadmium, lead, zinc, copper, and arsenic in the tailings. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the stabilizer for controlling heavy metal pollution in copper mine tailings and its application process according to the present invention.

[0034] Figure 2 The image shows the XRD pattern of the stabilizer of this invention reacting with cadmium (Cd).

[0035] Figure 3 The image shows the XRD pattern of the stabilizer of the present invention reacting with arsenic (As).

[0036] Figure 4 The image shows the XRD pattern of the stabilizer of the present invention reacting with zinc (Zn).

[0037] Figure 5 The results are EDS analysis of stabilized lead-zinc mine tailings. Detailed Implementation

[0038] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0039] The stabilizer of this invention consists of a base component A and a reinforcing component B. Base component A is prepared by activation of the following components: polyaluminum ferric chloride, polyferric sulfate, calcium hydroxide, calcium carbonate, and iron oxide. Reinforcing component B is sodium silicate, prepared as an aqueous solution for use.

[0040] When tailings contain at least one of the heavy metals arsenic, cadmium, lead, zinc, and copper, with arsenic content ≤5000 mg / kg, lead content ≤5000 mg / kg, zinc content ≤5000 mg / kg, and copper content ≤1000 mg / kg, after adding stabilizer base component A to copper ore beneficiation tailings and mixing it evenly, base component A, due to its fine particle size, can be evenly distributed among the tailings particles. After adding the strengthening component B aqueous solution, the stabilizer hydrolyzes to produce polynuclear hydroxyl ions, chain colloids, etc., which react with free cadmium, arsenic, zinc, lead, and other heavy metal ions in the tailings to generate a series of substances such as Cd4Al2O6Cl2·10H2O, Al2(AsO4)(OH)3·3H2O, and Zn5(OH)8Cl2·H2O (see...). Figure 2 , Figure 3 , Figure 4 (Example) On the other hand, it simultaneously undergoes a series of physicochemical reactions such as bridging, polymerization, and adsorption with water-soluble heavy metals and mineral particles, preventing the oxidation of sulfides and the leaching of heavy metals in the tailings. Refer to the EDS test results of stabilized lead-zinc mine tailings ( Figure 5 For example, heavy metals such as arsenic, copper, and lead react with iron and aluminum hydrolysates in the stabilizer to form polynuclear polymers, which are then bound together.

[0041] Control example (without stabilizer)

[0042] To better illustrate the effectiveness of this invention in controlling heavy metal pollution, a leaching toxicity test was conducted on tailings from a copper mine without stabilizer treatment to examine the leaching of heavy metal pollutants in the tailings and to compare the results with those after solidification and stabilization. The heavy metal content of the copper mine tailings was arsenic 182.00 mg / kg, cadmium 143.13 mg / kg, lead 587.50 mg / kg, copper 807.5 mg / kg, and zinc 421.70 mg / kg.

[0043] The treatment method for this comparative example (without stabilizer) involved taking tailings from a copper mine without stabilizer and conducting leaching toxicity tests according to the requirements of the standard "Leaching Toxicity of Solid Waste - Horizontal Oscillation Method" (HJ557-2010). The relevant results are shown in Table 1. As can be seen from Table 1, the leaching solution from the copper mine tailings without stabilizer showed high concentrations of copper, zinc, and cadmium, exceeding the limits set by the "Integrated Wastewater Discharge Standard" (GB8978-1996). According to relevant national standards, the copper mine tailings belong to Class II industrial solid waste. Furthermore, the contents of cadmium, arsenic, lead, and zinc in the leaching solution all exceeded the national surface water environmental quality standards, indicating that the copper mine tailings pose a significant environmental pollution risk.

[0044] Example 1

[0045] To illustrate the practical application effect of this invention, the stabilizer and its application method for controlling heavy metal pollution in copper mine tailings were used to solidify and stabilize heavy metal pollutants in a copper mine beneficiation tailings. The heavy metal content of the copper mine tailings was arsenic 182.00 mg / kg, cadmium 143.13 mg / kg, lead 587.50 mg / kg, copper 807.5 mg / kg, and zinc 421.70 mg / kg.

[0046] Combination Figure 1 The methods for preparing the stabilizer and treating copper mine tailings in this embodiment are as follows:

[0047] Step (1): Put 55 kg of polyaluminum ferric chloride, 5 kg of polyferric sulfate, 30 kg of calcium hydroxide, 9 kg of calcium carbonate, and 1 kg of iron oxide into a ball mill and grind them until they all pass through a 200-mesh sieve to obtain basic component A;

[0048] Step (2): Put 1000g of copper mine tailings into a mixer;

[0049] Step (3): Take 25g of the stabilizer base component A obtained in step (1) and add it to the mixer in step (2) and mix it evenly with the copper tailings;

[0050] Step (4): Add 50 mL of a 0.3% sodium silicate aqueous solution to the material after mixing the basic component A and copper tailings in step (3) evenly, and control the moisture content to 25%;

[0051] Step (5): Curing the copper tailings with added stabilizer for 24 hours, and then storing them in the open for 300 days;

[0052] Step (6): Samples were taken from the copper ore tailings after curing and solidification, and leaching tests were conducted according to the requirements of the standard "Leaching Toxicity of Solid Waste - Horizontal Oscillation Method" (HJ557-2010). The relevant test results for curing times of 24 hours and 300 days are detailed in Table 1.

[0053] Heavy metals such as arsenic, cadmium, lead, zinc, and copper in copper ore tailings exist in two phases based on their solubility. One phase consists of one or more substances containing these heavy metals that are easily soluble in water. The other phase consists of sulfide minerals containing these heavy metals, along with small amounts of metal oxides, which are sparingly soluble in water. These latter sulfide minerals are also easily oxidized into water-soluble substances in the presence of water and oxygen. The stabilizer base component A of this invention, after being uniformly mixed with copper ore tailings, primarily functions to distribute evenly within the tailings particles. The addition of the reinforcing component B (sodium silicate) aqueous solution forms multipolar colloids such as aluminum hydroxide and iron hydroxide. Through chemical reactions and physical processes such as adsorption, bonding, bridging, and trapping, these colloids aggregate arsenic, cadmium, lead, zinc, and copper heavy metal ions and their easily soluble substances (see details). Figure 5 This stabilizes and solidifies heavy metals such as arsenic, cadmium, lead, zinc, and copper, preventing them from leaching into the water. Simultaneously, the multipolar colloids such as aluminum hydroxide and ferric hydroxide, along with the water-insoluble calcium carbonate and iron oxide in the stabilizer, further prevent the sulfide minerals containing arsenic, cadmium, lead, or zinc in the tailings from being further oxidized to form water-soluble substances. As shown in Table 1, compared to the control without stabilizer, the stabilizer of this invention has a fine particle size, uniform distribution, and rapid onset of action. After 24 hours of curing, the concentrations of heavy metal pollutants arsenic, cadmium, lead, zinc, and copper in the leachate are lower than the limits of the "Integrated Wastewater Discharge Standard" (GB8978-1996) and also lower than the Class III water standard limits of the "Surface Water Environmental Quality Standard." The solidification and stabilization effect of arsenic, cadmium, lead, and zinc heavy metal pollutants is very significant; the solidification and stabilization effect does not decrease after 300 days of open-air storage, further proving that the stabilizer of this invention has a clear mechanism and outstanding effect in solidifying and stabilizing heavy metal pollutants in copper ore beneficiation tailings.

[0054] Example 2

[0055] To illustrate the practical application effect of this invention, the stabilizer and its application method were used to solidify and stabilize heavy metal pollutants in tailings waste rock from a copper mine. The heavy metal content of the copper mine tailings was arsenic 182.00 mg / kg, cadmium 143.13 mg / kg, lead 587.50 mg / kg, copper 807.5 mg / kg, and zinc 421.70 mg / kg.

[0056] Combination Figure 1 The method for preparing the stabilizer and treating the copper mine tailings in this embodiment is as follows:

[0057] Step (1): Based on a total mass of 100%, the following raw materials are put into a ball mill and ground in proportion. All of them pass through a 200-mesh sieve to obtain stabilizer base component A: 40% polyaluminum ferric chloride, 5% polyferric sulfate, 45% calcium hydroxide, 9.8% calcium carbonate, and 0.2% iron oxide;

[0058] Step (2): Put 1000g of copper mine tailings into a mixer;

[0059] Step (3): Take 20g of the stabilizer base component A obtained in step (1) and add it to the mixer in step (2) and mix it evenly with the copper tailings to obtain a mixture;

[0060] Step (4): Add 50 mL of a 0.3% sodium silicate aqueous solution to the mixture obtained in step (3) to obtain a solidified stabilized body;

[0061] Step (5): Curing the solidified stabilized body for 24 hours; then storing it outdoors for 300 days;

[0062] Step (6): Samples were taken from the cured and stabilized copper ore tailings, and leaching tests were conducted according to the requirements of the standard "Leaching Toxicity Method for Solid Waste - Horizontal Oscillation Method" (HJ557-2010). The test results are shown in Table 1.

[0063] Example 3

[0064] To illustrate the practical application effect of the present invention, the heavy metal pollutants in the tailings of a copper mine were stabilized and controlled.

[0065] The heavy metal content of the tailings of a copper mine is arsenic 182.00 mg / kg, cadmium 143.13 mg / kg, lead 587.50 mg / kg, copper 807.5 mg / kg, and zinc 421.70 mg / kg.

[0066] Combination Figure 1 The method for preparing the stabilizer and treating the copper mine tailings in this embodiment is as follows:

[0067] Step (1): Based on a total mass of 100%, the following raw materials are put into a ball mill and ground in proportion. All of them pass through a 200-mesh sieve to obtain stabilizer base component A: 44% polyaluminum ferric chloride, 5% polyferric sulfate, 49% calcium oxide, 1.8% calcium carbonate, and 0.2% iron oxide;

[0068] Step (2): Take 5000g of dry tailings from a copper mine and put it into a mixer;

[0069] Step (3): Take 80g of the stabilizer base component A obtained in step (1) and add it to the mixer in step (2) and mix it evenly with the copper tailings to obtain a mixture;

[0070] Step (4): Add 700 mL of a 0.3% sodium silicate aqueous solution to the mixture obtained in step (3) to obtain a solidified stabilized body;

[0071] Step (5): Curing the solidified and stabilized product for 48 hours; then storing it outdoors for 300 days.

[0072] Step (6): Samples were taken from the cured copper tailings and leaching tests were conducted according to the requirements of the standard "Horizontal Oscillation Method for Leaching Toxicity of Solid Waste" (HJ557-2010). The test results are shown in Table 1.

[0073] Example 4

[0074] To illustrate the practical application effect of this invention, the heavy metal pollutants in the tailings of a copper mine were stabilized and controlled. The heavy metal content of the copper mine tailings was arsenic 182.00 mg / kg, cadmium 143.13 mg / kg, lead 587.50 mg / kg, copper 807.5 mg / kg, and zinc 421.70 mg / kg.

[0075] Combination Figure 1 The method for preparing the stabilizer and treating the copper mine tailings in this embodiment is as follows:

[0076] Step (1): Based on a total mass of 100%, the following raw materials are put into a ball mill and ground in proportion. All of them pass through a 200-mesh sieve to obtain stabilizer base component A: 40% polyaluminum ferric chloride, 9% polyferric sulfate, 47% calcium oxide, 3.8% calcium carbonate, and 0.2% iron oxide;

[0077] Step (2): Take 5000g of dry tailings from a copper mine and put it into a mixer;

[0078] Step (3): Take 50g of the stabilizer base component A obtained in step (1) and add it to the mixer in step (2) and mix it evenly with the copper tailings to obtain a mixture;

[0079] Step (4): Add 700 mL of a 0.1% sodium silicate aqueous solution to the mixture obtained in step (3) to obtain a solidified stabilized body;

[0080] Step (5): Curing the solidified stabilized body for 48 hours; then storing it outdoors for 300 days.

[0081] Step (6): Take samples of the solidified stabilized body and conduct leaching tests according to the requirements of the standard "Leaching Toxicity Method for Solid Waste - Horizontal Oscillation Method" (HJ557-2010). The test results are shown in Table 1.

[0082] Table 1. Results of stabilization test of copper mine tailings (Method HJ557-2010) (Unit: mg / L).

[0083] .

[0084] The above data indicates that when tailings contain at least one of the heavy metals arsenic, cadmium, lead, zinc, and copper, with arsenic content ≤5000 mg / kg, lead content ≤5000 mg / kg, zinc content ≤5000 mg / kg, and copper content ≤1000 mg / kg, and the stabilizer particles are less than 200 mesh, it can better mix thoroughly with the equally fine copper ore tailings and distribute evenly among the various minerals. Under the action of the strengthening components and water, polyaluminum ferric chloride and calcium hydroxide hydrolyze and immediately undergo a series of chemical reactions with heavy metals such as cadmium, arsenic, lead, and zinc, generating a series of stabilizing substances such as Cd4Al2O6Cl2·10H2O, Al2(AsO4)(OH)3·3H2O, and Zn5(OH)8Cl2·H2O. See details... Figure 2 , Figure 3 , Figure 4 Example. Simultaneously, complex physicochemical mineralization processes such as agglomeration, polymerization, and physical adsorption occur, such as... Figure 5 Arsenic, copper, lead, and other heavy metals in the solution react with iron and aluminum to form polynuclear polymers, which are then solidified together, significantly reducing the toxicity and leaching rate of the heavy metals. Sodium silicate is selected as a reinforcing agent, which works synergistically with the basic component A to make the heavy metal minerals generated during the solidification and stabilization process more stable. After stabilization, the copper ore tailings are transformed from Class II solid waste to Class I solid waste, greatly reducing the risk of environmental pollution. As can be seen from the examples (Table 1), the concentration of heavy metal pollutants in the toxic leachate after stabilization is far lower than the limit of the Integrated Wastewater Discharge Standard (GB8978-1996) and also lower than the corresponding limit of Class III water quality standard of the Surface Water Environmental Quality Standard. The concentrations of copper, zinc, lead, cadmium, and arsenic in the leachate decreased from 0.52 mg / L, 2.36 mg / L, 0.27 mg / L, 0.16 mg / L, and 0.31 mg / L before solidification and stabilization to below 0.0023 mg / L, 0.05 mg / L, 0.001 mg / L, 0.0033 mg / L, and 0.0046 mg / L after stabilization, respectively, with solidification rates reaching 99.56%, 97.88%, 99.63%, 97.94%, and 98.52%. The stabilization effect remained unchanged after 300 days of open-air storage. Therefore, the stabilizer for controlling heavy metal pollution in copper ore tailings of this invention is a fast-acting and effective heavy metal solidification and stabilization agent.

Claims

1. A stabilizer for controlling heavy metal pollution in copper ore tailings, characterized in that: It includes basic component A and reinforcing component B; 55 kg of polyaluminum ferric chloride, 5 kg of polyferric sulfate, 30 kg of calcium hydroxide, 9 kg of calcium carbonate, and 1 kg of iron oxide were placed in a ball mill and ground until all components passed through a 200-mesh sieve. The mixture was then activated to obtain the basic component A. The reinforcing component B is a 0.3% sodium silicate aqueous solution; The polyaluminum ferric chloride is an industrial-grade product, containing ≥26% alumina, 3%–6% iron oxide, ≥65% basicity, and ≤0.0003% arsenic. The polyferric sulfate, calcium hydroxide, calcium carbonate, iron oxide, and sodium silicate are industrial-grade products or reagent-grade products. When the heavy metal content of copper tailings is arsenic 182.00 mg / kg, cadmium 143.13 mg / kg, lead 587.50 mg / kg, copper 807.5 mg / kg, and zinc 421.70 mg / kg, take 25g of basic component A and add it to 1000g of copper tailings (dry weight) and stir; add 50mL of strengthening component B and water at the same time, controlling the moisture content to 25%; and cure for 24 hours.

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