Vulcanized slag treatment method

Abstract

The invention discloses a treatment method of sulfide slag, and relates to the technical field of slag treatment. The treatment method of the vulcanized slag comprises the following steps: S10, mixing the vulcanized slag with water to obtain a slag-water mixture, and introducing air into the slag-water mixture to carry out aeration oxidation reaction to obtain an oxidized slag-water mixture; s20, adding a pH regulator into the oxidized slag-water mixture to obtain slurry, and adding an admixture into the slurry to obtain slurry; s30, the slurry is cured, and cured sulfurized slag is obtained; wherein the admixture comprises steel slag powder, fly ash powder and slag powder. According to the treatment method disclosed by the invention, the industrial solid waste is taken as the admixture, and sulfate radicals generated by the vulcanized slag and the admixture are cemented and cured, so that the curing strength and long-term stability of a cemented body are remarkably improved, and the safe treatment cost of the vulcanized slag is reduced; the method can be used for solving the problems of high treatment cost and poor long-acting stability of the existing sulfide slag treatment method.

Description

Technical Field

[0001] The invention relates to the technical field of slag treatment, and in particular to a method for treating sulfide slag. Background Art

[0002] Sulfide ore is a general term for a series of sulfur-containing minerals in nature. Common sulfide ores include pyrite, chalcopyrite, bornite, lead-zinc ore, etc. They are important minerals used to smelt sulfur, sulfuric acid, and some non-ferrous metals. A series of mining surrounding rocks, ore dressing tailings, and smelting waste slag produced during the mining and smelting of sulfide ores are separated from the original closed reduction system and exposed to the surface oxidation environment. Under the long-term physical, chemical and biological effects, the sulfur-containing components in them are oxidized to produce acidic mine wastewater rich in sulfate (pH 2-5), while releasing a large amount of heavy metal ions (such as Fe, Mn, Pb, Zn, etc.), which pollute the soil and groundwater environment in the neighboring areas and have a serious impact on the life, health and safety of people around the mining area.

[0003] For a long time, the treatment methods for sulfide slag produced during sulfide ore mining and smelting are pit filling or tailings pond storage. Both treatment methods require the use of materials with certain cementitious activity (such as cement). The basic principle is to use the hydration products of cementitious materials such as hydrated calcium silicate and calcium sulfonite to mechanically wrap the originally loose and fine-grained sulfide slag, thereby isolating the surrounding oxygen and water bodies and preventing the further oxidation of sulfur-containing components to release new pollution factors. Although the above treatment methods have good effects, they have shortcomings in long-term effectiveness and economy. The reasons are as follows: 1) Sulfide slag, especially tailings produced by ore dressing and waste slag produced during smelting, has extremely fine particles (average particle size <40μm), and physical wrapping and solidification requires a large amount of cementitious materials, resulting in high costs; 2) The long-term effectiveness of the treatment method is poor, and the mechanical wrapping of cementitious materials does not change the original structure inside the sulfide slag. Once the internal structure of the solidified body is exposed under the long-term rainwater scouring and biological erosion on the surface, oxidation reactions will still occur and new pollutants will be produced. Summary of the invention

[0004] The main purpose of the present invention is to provide a method for treating sulfide slag, aiming to solve the problems of high treatment cost and poor long-term stability of existing sulfide slag treatment methods.

[0005] To achieve the above object, the present invention provides a method for treating sulfide slag, comprising the following steps:

[0006] Mixing sulfide slag and water to obtain a slag-water mixture, introducing air into the slag-water mixture for aeration oxidation reaction to obtain an oxidized slag-water mixture;

[0007] adding a pH regulator to the oxidized slag-water mixture to obtain a slurry, and adding an admixture to the slurry to obtain a slurry;

[0008] Curing the slurry to obtain solidified sulfide slag;

[0009] Wherein, the admixture includes steel slag powder, fly ash powder and slag powder.

[0010] In one embodiment, the mass ratio of the sulfide slag to water is (1-5):1.

[0011] In one embodiment, in the step of introducing air into the slag-water mixture for aeration and oxidation reaction, the total aeration rate when introducing air is 5 to 50 m 3 / t.

[0012] In one embodiment, the addition amount of the steel slag powder is 5-10% of the total mass of the slurry, the addition amount of the fly ash powder is 5-20% of the total mass of the slurry, and the addition amount of the slag powder is 5-15% of the total mass of the slurry.

[0013] In one embodiment, the calcium oxide content in the steel slag powder is greater than 35%, and the particle size of the steel slag powder is less than 80 μm; and / or,

[0014] The aluminum oxide content in the fly ash powder is greater than 15%; and / or,

[0015] The mass coefficient of the slag powder is greater than 1.2, and the particle size of the slag powder is less than 40 μm.

[0016] In one embodiment, the pH value of the slurry is 7-9.

[0017] In one embodiment, the step of adding an admixture to the slurry further comprises adding water, and the amount of water added is 10-20% of the total mass of the slurry and the admixture.

[0018] In one embodiment, the steps of mixing sulfide slag and water to obtain a slag-water mixture, introducing air into the slag-water mixture for aeration oxidation reaction, and obtaining an oxidized slag-water mixture include:

[0019] The sulfide slag, water and an oxidant are mixed to obtain a slag-water mixture, and air is introduced into the slag-water mixture to perform an aeration oxidation reaction to obtain an oxidized slag-water mixture.

[0020] In one embodiment, the oxidant includes at least one of hydrogen peroxide, potassium permanganate and persulfate, and the added amount of the oxidant is 2-5% of the total mass of the slag-water mixture.

[0021] In one embodiment, the pH adjuster is alkaline solid waste, and the alkaline solid waste includes at least one of carbide slag, red mud slag and limestone powder.

[0022] The method for treating sulfide slag provided by the technical solution of the present invention first oxidatively soaks the sulfide slag with water and continuously aerates the mixture, so that the slag-water mixture is converted into an oxidized slag-water mixture. After oxidation, the sulfur-containing components in the sulfide slag are oxidized into sulfate ions; subsequently, a pH regulator is added to neutralize the acidity of the oxidized slag-water mixture, so as to promote the hydrolysis and precipitation of heavy metal ions such as iron and manganese in the oxidized slag-water mixture, and provide an alkaline environment for subsequent hydration reactions; subsequently, an admixture containing sufficient calcium source and aluminum source is added, so that the sulfate ions and the calcium source and aluminum source in the admixture are hydrated in an alkaline environment, so as to promote the formation of initial hydration products such as hydrated calcium silicate and hydrated calcium aluminosilicate, and the formation of important mineral calcium sulfonate that determines the long-term stability of the consolidated body, so as to form a slurry to be cemented and solidified; finally, the obtained slurry is cured to achieve stable cementation and solidification of the sulfide slag. Therefore, the treatment method of the present invention is used to treat sulfide slag, which reduces the harm of sulfur components, a potential source of pollution factors in sulfide slag, and effectively reduces the heavy metal leaching concentration of sulfide slag cement, which can reduce the harm caused by direct exposure of sulfide slag. The pyrite slag treatment method provided by the present invention uses industrial solid waste as an admixture, oxidizes the sulfur-containing components in the pyrite slag into sulfate, and utilizes the self-cementing activity of sulfate to participate in the generation of calcium sulfonite, strengthens the chemical reaction between the cementing material and the cemented material, and improves the curing strength and long-term stability of the cementing body, thereby improving the long-term stability of the treatment of sulfide slag. Compared with the method of using conventional cementitious materials to treat sulfide slag, the technical solution of the present invention replaces cement and other cementitious materials with admixtures, and chemically combines with the cemented material instead of simply physically coating the admixture, which not only significantly improves the treatment effect of pyrite slag, but also reduces the use of cementitious materials, reuses industrial solid waste, and reduces the safe treatment cost of sulfide slag. Therefore, the technical solution of the present invention can be used to solve the problems of high treatment cost and poor long-term stability of existing sulfide slag treatment methods. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0025] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0026] Sulfide ore is a general term for a series of sulfur-containing minerals in nature. Common sulfide ores include pyrite, chalcopyrite, bornite, lead-zinc ore, etc. They are important minerals used to smelt sulfur, sulfuric acid, and some non-ferrous metals. A series of mining surrounding rocks, ore dressing tailings, and smelting waste slag produced during the mining and smelting of sulfide ores are separated from the original closed reduction system and exposed to the surface oxidation environment. Under the long-term physical, chemical and biological effects, the sulfur-containing components in them are oxidized to produce acidic mine wastewater rich in sulfate (pH 2-5), while releasing a large amount of heavy metal ions (such as Fe, Mn, Pb, Zn, etc.), which pollute the soil and groundwater environment in the neighboring areas and have a serious impact on the life, health and safety of people around the mining area.

[0027] In view of this, the present invention proposes a method for treating sulfide slag, comprising the following steps:

[0028] Mixing sulfide slag and water to obtain a slag-water mixture, introducing air into the slag-water mixture for aeration oxidation reaction to obtain an oxidized slag-water mixture;

[0029] adding a pH regulator to the oxidized slag-water mixture to obtain a slurry, and adding an admixture to the slurry to obtain a slurry;

[0030] Curing the slurry to obtain solidified sulfide slag;

[0031] Wherein, the admixture includes steel slag powder, fly ash powder and slag powder.

[0032] The technical solution of the present invention is to oxidatively soak the sulfide slag with water and continuously aerate the mixture, so that the slag-water mixture is converted into an oxidized slag-water mixture. After oxidation, the sulfur-containing components in the sulfide slag are oxidized into sulfate, and a large amount of acidic wastewater containing sulfate is generated at the same time; subsequently, a pH regulator is added to neutralize the acidity of the oxidized slag-water mixture, promote the hydrolysis and precipitation of heavy metal ions such as iron and manganese in the oxidized slag-water mixture, and provide an alkaline environment for subsequent hydration reactions; subsequently, an admixture containing sufficient calcium source and aluminum source is added, so that the sulfate, calcium source and aluminum source in the pyrite slag are hydrated in an alkaline environment, promote the formation of initial hydration products hydrated calcium silicate and hydrated calcium aluminosilicate, and the formation of important mineral calcium sulfonate that determines the long-term stability of the consolidated body, so as to form a slurry to be cemented and solidified; finally, the obtained slurry is cured to achieve stable cementation and solidification of the sulfide slag. The treatment method of the present invention is used to treat sulfide slag, which reduces the harm of sulfur component, a potential pollution source factor, effectively reduces the heavy metal leaching concentration of the sulfide slag cement body, and can reduce the harm caused by direct exposure of the sulfide slag.

[0033] The conventional method for treating sulfide slag is to directly mix a material with a certain cementing activity (such as cement) with the sulfide slag, and use the hydration products of cementing materials such as hydrated calcium silicate and ettringite to mechanically wrap the originally loose and fine-grained sulfide slag, thereby isolating the surrounding oxygen and water. Compared with the method of using conventional cementing materials to treat sulfide slag, the technical solution of the present invention uses industrial solid waste as an admixture, and uses the admixture to replace cement and other cementing materials. The active ingredients in the admixture (mainly active calcium and active aluminum) are combined with the sulfate generated by the pyrite slag to generate a framework ettringite, which can strengthen the chemical reaction between the cementing material and the cemented material, enhance the long-term solidification strength and durability of the consolidated body, and thus improve the long-term stability of the treatment of sulfide slag. Moreover, the technical solution of the present invention significantly improves the treatment effect of pyrite slag by chemically combining the admixture with the binder rather than simply physically coating it. It not only reduces the treatment cost, but also can effectively solidify and stabilize the heavy metals in the sulfide slag, reducing the stacking of waste such as steel slag, fly ash and slag.

[0034] In an embodiment of the present invention, the mass ratio of the sulfide slag to water is (1-5): 1. Setting the mass ratio of the sulfide slag to water to (1-5): 1 is conducive to controlling the moisture content of the sulfide slag and fully oxidizing the sulfur components of the sulfide slag to sulfate.

[0035] In the embodiment of the present invention, in the step of introducing air into the slag-water mixture for aeration and oxidation reaction, the total aeration rate when introducing air is 5 to 50 m 3The aeration rate of the air introduced is controlled within the above range, so that the sulfur-containing components in the sulfide slag are fully oxidized into sulfate radicals, thereby improving the self-cementing activity of the sulfate radicals.

[0036] In an embodiment of the present invention, the amount of the steel slag powder added is 5-10% of the total mass of the slurry, the amount of the fly ash powder added is 5-20% of the total mass of the slurry, and the amount of the slag powder added is 5-15% of the total mass of the slurry. Setting the amount of the steel slag powder, fly ash powder and slag powder within the above range can provide sufficient calcium source and aluminum source, which is conducive to promoting the formation of the initial hydration products hydrated calcium silicate and hydrated calcium aluminosilicate and the formation of the later hydration product framework ettringite, thereby improving the solidification strength and long-term stability of the sulfide slag.

[0037] In an embodiment of the present invention, the calcium oxide content in the steel slag powder is greater than 35%, and the particle size of the steel slag powder is less than 80 μm. Using steel slag powder with a calcium oxide (CaO) content greater than 35% and a particle size less than 80 μm is beneficial to improving the reactivity of steel slag particles and fully releasing the active calcium, magnesium and aluminum components therein.

[0038] In an embodiment of the present invention, the aluminum oxide content in the fly ash powder is greater than 15%. Selecting fly ash powder with an aluminum oxide (Al2O3) content greater than 15% is conducive to providing sufficient aluminum source.

[0039] In an embodiment of the present invention, the mass coefficient of the slag powder is greater than 1.2, and the particle size of the slag powder is less than 40 μm. The mass coefficient K of the slag powder = (CaO + MgO + Al2O3) / (SiO2 + MnO + TiO2). The mass coefficient K can be used to quantify the reactivity of slag powder under specific conditions, that is, the ability of slag powder to react with calcium hydroxide (Ca(OH)2) in cement hydration products to generate substances such as calcium silicate hydrate (CSH) with gelling properties. Setting the activity coefficient K of the slag powder to be greater than 1.2 and the particle size to be less than 40 μm can fully guarantee the reactivity of the slag powder.

[0040] In an embodiment of the present invention, the pH value of the slurry is 7 to 9. When the pH value of the slurry is 7 to 9, it is conducive to the hydration reaction of sulfate and the calcium source and aluminum source in the admixture, and promotes the formation of the initial hydration products of hydrated calcium silicate and hydrated calcium aluminosilicate, as well as the formation of ettringite which determines the long-term stability of the consolidated body.

[0041] In an embodiment of the present invention, the step of adding an admixture to the slurry further comprises adding water, wherein the amount of water added is 10-20% of the total mass of the slurry and the admixture. During the mixing of the slurry and the admixture, water is sprayed regularly for moisture retention to promote the hydration reaction.

[0042] In an embodiment of the present invention, the steps of mixing sulfide slag and water to obtain a slag-water mixture, introducing air into the slag-water mixture for aeration oxidation reaction, and obtaining an oxidized slag-water mixture include:

[0043] The sulfide slag, water and an oxidant are mixed to obtain a slag-water mixture, and air is introduced into the slag-water mixture to perform an aeration oxidation reaction to obtain an oxidized slag-water mixture.

[0044] In addition to continuous aeration, adding a certain amount of oxidant can accelerate the rapid oxidation of sulfur-containing components and shorten the treatment time.

[0045] In an embodiment of the present invention, the oxidant includes at least one of hydrogen peroxide, potassium permanganate and persulfate, and the amount of the oxidant added is 2-5% of the total mass of the slag-water mixture. The oxidant includes at least one of hydrogen peroxide, potassium permanganate and persulfate, which means that the oxidant can be any one of hydrogen peroxide, potassium permanganate and persulfate, or two or more of hydrogen peroxide, potassium permanganate and persulfate, all of which belong to the protection scope of the present invention. The amount of the oxidant added is 2-5% of the total mass of the slag-water mixture. Within this range, the amount of the oxidant added can be 2%, 3%, 4% and 5% of the total mass of the slag-water mixture.

[0046] In an embodiment of the present invention, the pH regulator is alkaline solid waste, and the alkaline solid waste includes at least one of carbide slag, red mud slag and limestone powder. The alkaline solid waste can be any one of carbide slag, red mud slag and limestone powder, or two or more of carbide slag, red mud slag and limestone powder, all of which belong to the protection scope of the present invention. In the technical solution of the present invention, the alkaline solid waste can provide sufficient silicon source and aluminum source in addition to alkalinity. Therefore, the use of alkaline solid waste as a pH regulator can fully neutralize H in the slag-water mixture. + , avoiding acidity erosion of subsequent solid bodies, while promoting the hydrolysis and precipitation of heavy metal ions such as iron and manganese, providing a good medium environment for the generation of subsequent hydration products, and providing silicon and aluminum sources to help generate ettringite. It should be noted that grinding the alkaline solid waste to a particle size of less than 40 μm before use is conducive to the rapid progress of the hydration reaction.

[0047] In the embodiment of the present invention, there is no restriction on the curing method of the slurry, and the slurry can be cured according to conventional curing processes until the slurry meets the standards.

[0048] The technical solution of the present invention is further described in detail below in conjunction with specific embodiments. It should be understood that the following embodiments are only used to explain the present invention, and are not used to limit the present invention.

[0049] The pyrite slag samples used in the various embodiments of the present invention are the same, and their main chemical components are shown in Table 1.

[0050] Table 1 Main chemical components of pyrite slag

[0051] <![CDATA[SiO2]]> <![CDATA[Al2O3]]> <![CDATA[Fe2O3]]> <![CDATA[K2O]]> <![CDATA[SO3]]> MgO <![CDATA[TiO2]]> CaO <![CDATA[P2O5]]> content 51.17％ 24.13％ 8.82％ 7.11％ 3.15％ 2.26％ 2.18％ 0.63％ 0.45％

[0052] Example 1

[0053] A method for treating sulfide slag comprises the following steps:

[0054] (1) Add 20 kg of tap water to 50 kg of pyrite slag (average particle size 40 μm) for elution to form a slag-water mixture, and aerate the slag-water mixture at an aeration rate of 10 m 3 / t. During the leaching process, hydrogen peroxide was added (the amount added was 2% of the total mass of the slag-water mixture). When the pH value of the leaching liquid showed no significant change within 2 hours, the leaching and aeration operations were stopped, and the leaching liquid and the oxidized sulfide slag were collected to obtain the oxidized slag-water mixture;

[0055] (2) mixing the oxidized slag-water mixture and alkaline red mud powder with a particle size of 40 μm (the addition amount is 10% of the mass of the oxidized slag-water mixture) in a mixer to obtain a slurry, and then adding steel slag powder (particle size of 35 μm, CaO content of 45%), fly ash powder (particle size of 10 μm, Al2O3 content of 22%), and slag powder (particle size of 30 μm, activity coefficient K=1.5) of 5% of the total mass of the slurry, and adding water of 10% of the total mass of the above mixture to keep moisture during the stirring process to obtain a slurry;

[0056] (3) The fully stirred slurry was transferred to a mold for pressing and curing for 5 days. The heavy metal leaching concentration, compressive strength and permeability coefficient of the solid body were tested in a weakly acidic environment according to the "Solid Waste Leaching Toxicity Method-Sulfuric Acid and Nitric Acid Method" (HJ / T299-2007). The test results are shown in Table 2.

[0057] Table 2 Performance test results of Example 1

[0058] category Fe Mn Pb Zn Compressive strength Permeability coefficient result 7.5 μg / L 3.6 μg / L 2.8 μg / L 3.2 μg / L 3.6MPa <![CDATA[6.8×10 -8 cm / s]]>

[0059] Example 2

[0060] Compared with Example 1, the difference is that in step (2), the amount of steel slag powder added is 10% of the total mass of the slurry; the amount of fly ash powder added is 20% of the total mass of the slurry; the amount of slag powder added is 15% of the total mass of the slurry; and the amount of water added is 20% of the total mass of the slurry and the admixture.

[0061] The test results of heavy metal leaching concentration, compressive strength and permeability coefficient of the consolidated body are shown in Table 3.

[0062] Table 3 Performance test results of Example 2

[0063] category Fe Mn Pb Zn Compressive strength Permeability coefficient result 5.8 μg / L 1.2 μg / L 0μg / L 0μg / L 4.8MPa <![CDATA[2.6×10 -8 cm / s]]>

[0064] Example 3

[0065] Compared with Example 1, the difference is that no hydrogen peroxide is added in step (1);

[0066] In step (2), the amount of steel slag powder added is 5% of the total mass of the slurry; the amount of fly ash powder added is 10% of the total mass of the slurry; the amount of slag powder added is 8% of the total mass of the slurry; and the amount of water added is 10% of the total mass of the slurry and admixtures.

[0067] The test results of heavy metal leaching concentration, compressive strength and permeability coefficient of the consolidated body are shown in Table 4.

[0068] Table 4 Performance test results of Example 3

[0069] category Fe Mn Pb Zn Compressive strength Permeability coefficient result 11.6 μg / L 4.8 μg / L 3.9 μg / L 6.2 μg / L 2.6MPa <![CDATA[8.2×10 -8 cm / s]]>

[0070] Comparative Example 1

[0071] Portland cement and pyrite tailings powder were mixed in a mass ratio of 1:2 to obtain a mixture, water (40% of the total mass of the mixture) was added to the mixture for stirring to obtain a slurry, and the slurry was placed in a mold for compression molding and cured for 5 days.

[0072] The test results of heavy metal leaching concentration, compressive strength and permeability coefficient of the consolidated body are shown in Table 5.

[0073] Table 5 Performance test results of comparative example 1

[0074] category Fe Mn Pb Zn Compressive strength Permeability coefficient result 68.2 μg / L 18.2 μg / L 10.9 μg / L 12.7 μg / L 1.2MPa <![CDATA[8.6×10 -7 cm / s]]>

[0075] Comparative Example 2

[0076] The universal cementitious material and the sulfide slag are mixed in a mass ratio of 1:2 to obtain a mixture; the basic components of the universal cementitious material include fly ash, slag, steel slag, water glass, a water reducer and a small amount of cement component. Water (40% of the total mass of the mixture) is added to the mixture for stirring to obtain a slurry, and the slurry is put into a mold for compression molding and cured for 5 days.

[0077] The test results of heavy metal leaching concentration, compressive strength and permeability coefficient of the consolidated body are shown in Table 6.

[0078] Table 6 Performance test results of comparative example 2

[0079] category Fe Mn Pb Zn Compressive strength Permeability coefficient result 36.7 μg / L 18.2 μg / L 12.7 μg / L 17.5 μg / L 2.5Mpa <![CDATA[2.8×10 -7 cm / s]]>

[0080] It can be seen from the above test results that under the same material dosage and curing time, the treatment methods of Example 1 and Example 3 can achieve a certain curing and stabilizing effect on pyrite slag, but the heavy metal curing effect and anti-penetration ability of ordinary Portland cement (Comparative Example 1) and general-purpose cementitious material (Comparative Example 2) are worse than those of Example 1 and Example 3. This is because the curing and stabilization of traditional cement and cementitious material is mechanical coating, which does not change the internal structure of the solid body, resulting in the cement solid body and the cementitious material solid body being more susceptible to erosion and damage in an acidic leaching environment, releasing more heavy metal ions, while the treatment methods of Example 1 and Example 3 form a more compact self-cementing structure by stimulating the gelling activity of the pyrite slag itself, and the stability under the long-term weathering and erosion is better. The comparison results of Example 1, Example 2, and Example 3 show that the curing and stabilizing effect of pyrite slag can be further improved by adding oxidizing agents to assist impregnation, increasing the amount of admixtures, and other measures.

[0081] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A method for treating sulfide slag, characterized in that: The following steps are involved: Mixing sulfide slag and water to obtain a slag-water mixture, introducing air into the slag-water mixture for aeration oxidation reaction to obtain an oxidized slag-water mixture; adding a pH regulator to the oxidized slag-water mixture to obtain a slurry, and adding an admixture to the slurry to obtain a slurry; Curing the slurry to obtain solidified sulfide slag; Wherein, the admixture includes steel slag powder, fly ash powder and slag powder.

2. The method for treating sulfide slag according to claim 1, characterized in that: The mass ratio of the sulfide slag to water is (1-5):

1.

3. The method for treating sulfide slag according to claim 1, characterized in that: In the step of introducing air into the slag-water mixture for aeration and oxidation reaction, the total aeration volume when introducing air is 5 to 50 m 3 / t.

4. The method for treating sulfide slag according to claim 1, characterized in that: The added amount of the steel slag powder is 5-10% of the total mass of the slurry, the added amount of the fly ash powder is 5-20% of the total mass of the slurry, and the added amount of the slag powder is 5-15% of the total mass of the slurry.

5. The method for treating sulfide slag according to claim 1, characterized in that: The calcium oxide content in the steel slag powder is greater than 35%, and the particle size of the steel slag powder is less than 80 μm; and / or, The aluminum oxide content in the fly ash powder is greater than 15%; and / or, The mass coefficient of the slag powder is greater than 1.2, and the particle size of the slag powder is less than 40 μm.

6. The method for treating sulfide slag according to claim 1, characterized in that: The pH value of the slurry is 7-9.

7. The method for treating sulfide slag according to claim 1, characterized in that: The step of adding admixture to the slurry further comprises adding water, wherein the amount of water added is 10-20% of the total mass of the slurry and the admixture.

8. The method for treating sulfide slag according to claim 1, characterized in that: The steps of mixing sulfide slag and water to obtain a slag-water mixture, introducing air into the slag-water mixture for aeration oxidation reaction to obtain an oxidized slag-water mixture include: The sulfide slag, water and an oxidant are mixed to obtain a slag-water mixture, and air is introduced into the slag-water mixture to perform an aeration oxidation reaction to obtain an oxidized slag-water mixture.

9. The method for treating sulfide slag according to claim 8, characterized in that: The oxidant includes at least one of hydrogen peroxide, potassium permanganate and persulfate, and the added amount of the oxidant is 2-5% of the total mass of the slag-water mixture.

10. The method for treating sulfide slag according to claim 1, characterized in that: The pH regulator is alkaline solid waste, and the alkaline solid waste includes at least one of carbide slag, red mud slag and limestone powder.