High-alkali and high-residual copper-molybdenum separation wastewater treatment method

Abstract

The invention discloses a high-alkali and high-residual copper-molybdenum separation wastewater treatment method. The treatment method comprises the following steps: simultaneously injecting acidic wastewater percolating from a waste rock storage yard in a mining area and high-alkali and high-residual copper-molybdenum separation wastewater into a mixing tank, adding a certain amount of a catalyst and an oxidizing agent to carry out catalytic oxidation reaction, and then adding a certain proportion of circulating slurry and carbide slag-lime milk mixed liquid into another reaction tank, aerating to fully mix and react until the pH value is neutral, entering a degassing and flocculating tank, adding a flocculating agent, finally entering a thickening tank for precipitation, and lifting clear liquid to a high-level water tank through a pump for mineral separation production; one part of underflow (neutralized slurry) is used as circulating slurry, and the other part of underflow (neutralized slurry) is output for treatment; a catalytic oxidation treatment process is adopted for high-alkali and high-residual copper-molybdenum separation wastewater formed by mixing acidic water, copper and sulfur concentrate overflow water and copper-molybdenum separation alkaline wastewater, the treated water quality reaches the national wastewater discharge standard, return water can be recycled, and the wastewater treatment efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of mineral processing, and in particular to a method for treating high-alkali and high-residue copper-molybdenum separation wastewater. Background Art

[0002] With the large-scale development of high-grade copper sulfide ore resources, the comprehensive utilization of low-grade copper sulfide ore has gradually attracted attention. Low-grade copper sulfide ore is often recovered by heap leaching and flotation processes. A large amount of acidic wastewater is generated during the mineral storage process. Acid mine wastewater has the characteristics of low pH value, high content of heavy metals (Fe, Cu, Mn) and sulfate. If it is directly discharged, when this toxic mixture flows into groundwater, rivers and lakes, it will cause a series of environmental problems and have serious impacts on human health.

[0003] Low-grade chalcopyrite often coexists with pyrite and molybdenite. At present, a large amount of lime is often added in the copper-sulfur separation process, and the amount of lime used is even as high as 50kg / t. The addition of a large amount of lime causes the mineral processing return water to contain a large amount of calcium ions, high treatment costs, and difficult to use the return water; a large amount of sodium sulfide is often added in the copper-molybdenum separation process, and the amount of sodium sulfide used is even as high as 36kg / t. The addition of a large amount of sodium sulfide causes the molybdenum processing return water to have a high COD. At the same time, there are other mineral processing reagents remaining, which makes the copper-molybdenum separation wastewater present the characteristics of high alkali and high residue, which is difficult to treat, high cost, and difficult to use the return water.

[0004] At present, the acidic water in the mining area and the return water from the flotation process are mixed and used, and the main problems are as follows:

[0005] 1. The overflow water of copper concentrate and molybdenum concentrate is strongly alkaline, while the seepage water from the waste rock dump in the mining area is weakly acidic, and the return water properties are greatly different.

[0006] 2. The overflow water of copper-sulfur concentrate and the drainage water of copper-molybdenum separation contain some fine mineral particles, which affect the return water treatment.

[0007] 3. The two kinds of return water with different properties are directly used in the process of mineral processing and production, and must be treated (mainly to reduce Cu 2+ , Ca 2+ , collectors, inhibitors, etc.) before it can be used for flotation operations; the amount of water to be treated is large and the treatment cost is high.

[0008] 4. The purification of mineral processing wastewater is a serious problem. The mineral processing plant is the main source of wastewater, which has a complex composition and contains a large amount of heavy metal ions and sulfate minerals, and these suspended fine particles form a colloidal solution that is difficult to treat. Therefore, it is of great significance to develop green and efficient treatment processes and supporting agents.

[0009] In view of this, the present invention is proposed. Summary of the invention

[0010] The purpose of the present invention is to provide a method for treating high-alkali and high-residue copper-molybdenum separation wastewater. The method of the present invention collects process water recovered from different copper mines separately, and performs multi-stage synergistic oxidation, which effectively avoids the influence of heavy metal ions in the return water on the flotation operation, ensures the mineral processing indicators, greatly reduces the amount of water carried away by the discharged ore pulp, the amount of reagent added, the amount of clean water used and the amount of wastewater, adopts new catalysts, oxidants and flocculants, uses less dosage, and is energy-saving and environmentally friendly.

[0011] In order to achieve the above-mentioned purpose of the present invention, the following technical scheme is specially adopted: a method for treating high-alkali and high-residue copper-molybdenum separation wastewater, which specifically comprises the following steps:

[0012] S1) feeding the high-alkali high-residue copper-molybdenum separation wastewater and the acidic wastewater to be treated into a mixing tank, adjusting the pH value, and then adding a catalyst and an oxidant to stir evenly for standby use;

[0013] S2) feeding the overflow water in the mixing tank after the treatment in S1) into the first reaction tank by gravity or pump, and simultaneously introducing a certain amount of compressed air and stirring sufficiently to make it react completely;

[0014] S3) feeding the overflow water in the first reaction tank after the treatment in S2) into the second reaction tank by gravity or pump, adding a pH adjuster to adjust the pH value, and simultaneously introducing a certain amount of compressed air and stirring sufficiently to make the reaction complete;

[0015] S4) The overflow water in the second reaction tank treated in S3) is fed to the degassing tank by gravity or pump. During the process of gravity feeding to the high-efficiency thickener, a certain amount of flocculant is fed by a metering pump. The flocculation reaction in the high-efficiency thickener is 1 to 2 minutes, and the precipitate and concentrate to obtain clarified liquid and sedimentation tank bottom flow. The clarified liquid is the qualified discharge water.

[0016] Furthermore, the acidic wastewater in S1) has a pH of 3.0 to 4.5, contains 200 to 500 mg / L TFe, 20 to 40 mg / L Cu, 80 to 150 mg / L Mn, and 100 to 150 mg / L Mg; SO4 2- 3000~6000mg / L;

[0017] The pH of the high-alkali high-residue copper-molybdenum separation wastewater is 10.5-11.8, and the COD is 600-1200 mg / L. 2- Ion concentration is 4000-7000mg / L, S x 2- 40-120mg / L, Na + 600-1000mg / L;

[0018] The dosage of the catalyst and oxidant is: catalyst 0.2-0.3 kg / m 3 Total water, oxidant 1.0~1.2kg / m 3 Total water;

[0019] The pH value is 3.5-4.5. After adding the catalyst and the oxidant, stir and mix for 3-5 minutes with a stirring intensity of 25r / min-40r / min.

[0020] Furthermore, the catalyst is a metabolite of a composite functional bacterial community mainly composed of Thiobacillus, and contains a large number of functional groups such as hydroxyl, sulfhydryl, carboxyl, and amino groups.

[0021] The functional group is obtained by culturing, separating and drying a thiobacillus liquid with ferrous chloride and ferrous nitrate in a ratio of 100:90.

[0022] The oxidant is a 27.5% to 30% hydrogen peroxide (H2O2) solution.

[0023] Furthermore, the amount of compressed air in S2) is 5 to 10 m 3 / min, stirring time is 15-20min, and stirring intensity is 25r / min-30r / min.

[0024] Further, the pH in S3) is 7.5-8.5, and the amount of pH regulator is 4.5-5.0 kg / m 3 Acidic water; compressed air volume is 5-10m 3 / min, stirring time is 15-20min, and stirring intensity is 25r / min-30r / min.

[0025] Furthermore, the pH regulator is a mixture of carbide slag and lime in a mass ratio of (0.2-0.5):1.

[0026] Furthermore, the amount of the flocculant in S4) is 2.8 to 3.5 g / m 3 Total water, flocculation particle settling rate is 20-50cm / min, compressed air volume is 5-10m 3 / min, stirring time is 15-20min, and stirring intensity is 25r / min-30r / min.

[0027] Furthermore, the flocculant is polyacrylamide with a molecular weight of ≥17 million.

[0028] Furthermore, the light transmittance of the clarified liquid obtained by the treatment method is ≥95%, the pH is 6.5-7.5, COD<60mg / L, SS<80mg / L, NH3-H<2mg / L, sulfide<1.0mg / L, Cu<0.5mg / L, and Ca200-300mg / L.

[0029] Furthermore, 20-30% of the bottom slag in the sedimentation tank is used as circulating slurry to return to the second reaction tank, and 70-80% is transported out for treatment.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) The method of the present invention is aimed at the acidic wastewater from the seepage of the waste rock dump in the mining area, the overflow water of the copper-sulfur concentrate and the alkaline wastewater from the copper-molybdenum separation. By adopting a new "catalytic oxidation treatment process", the method realizes the comprehensive treatment of the ore dressing wastewater with different processes and different properties, and greatly reduces the wastewater treatment cost.

[0032] (2) The method of the present invention has a good removal effect on mineral processing agents, copper-molybdenum separation agents, and heavy metals, can effectively remove a variety of pollutants, and is friendly to the water ecological environment.

[0033] (3) The catalyst and oxidant used in the present invention act synergistically and are biodegradable and widely available.

[0034] (4) The present invention adds a high molecular weight flocculant into the sedimentation tank to reduce the content of fine particles in the overflow water, thereby preventing the fine particles from circulating in the return water and causing high energy consumption or affecting the flotation separation of multiple metals. The flocculant in the present invention has an excellent sedimentation effect in treating mineral processing wastewater, solves the thorny wastewater challenges faced by industrial sustainable development and reduces environmental pollution, and promotes the widespread application of polymer flocculant PAM in the field of water treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a flow chart of a method for treating high-alkali and high-residue copper-molybdenum separation wastewater according to the present invention.

[0036] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work. DETAILED DESCRIPTION

[0037] The technical scheme of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and specific embodiments, but it will be understood by those skilled in the art that the following described embodiments are part of embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be considered as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention. If specific conditions are not specified in the embodiments, they are carried out according to normal conditions or conditions recommended by the manufacturer. If the manufacturer is not specified in the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0038] like Figure 1 As shown, the present invention provides a method for treating high-alkali and high-residue copper-molybdenum separation wastewater, and the treatment method specifically comprises the following steps:

[0039] (1) feeding the acidic water, overflow water from copper-sulfur concentrate, and high-alkali and high-residue copper-molybdenum separation wastewater into a mixing tank, controlling the pH in the tank to be 3.5-4.5 using a pH controller, and adding a catalyst and an oxidant and stirring for 3-5 minutes at a stirring intensity of 25 r / min-40 r / min;

[0040] (2) The overflow water in the mixing tank is fed to the first reaction tank by gravity or pump, and a certain amount of compressed air is introduced and fully stirred to make it react completely. The amount of compressed air is 5 to 10 m 3 / min, stirring time is 15-20min, stirring intensity is 25r / min-30r / min..

[0041] The catalyst is a metabolite of a composite functional bacterial community mainly composed of Thiobacillus, containing a large number of functional groups such as hydroxyl, sulfhydryl, carboxyl, and amino groups. The functional groups are obtained by culturing, separating, and drying Thiobacillus liquid with ferrous chloride and ferrous nitrate in a ratio of 100:90. The oxidizing agent is mainly a 27.5%-30% hydrogen peroxide (H2O2) solution;

[0042] (3) The overflow water in the first reaction tank is fed into the second reaction tank by gravity or pump, the carbide slag and lime are prepared into an emulsion state, and the emulsion is fed into the second reaction tank by a pump, and the pH of the liquid is adjusted to 7.5-8.5 by a pH controller, the stirring time is 15-20 minutes, and the stirring intensity is 25r / min-40r / min;

[0043] (4) The overflow water in the second reaction tank is fed to the degassing tank by gravity or pump. During the process of gravity feeding to the high-efficiency thickener, a certain amount of flocculant is fed by a metering pump. The water enters the high-efficiency thickener for flocculation reaction for 1 to 2 minutes, and then precipitates and concentrates. The overflow of the thickener, i.e., the clarified liquid, is the qualified discharge water, which can be pumped to a high-level water tank for use in mineral processing production, or discharged from the outlet. 30% of the bottom flow (neutralized mud) of the sedimentation tank is used as circulating slurry to return to the second reaction tank, the rest is discharged and stored, and 70% is transported for external treatment.

[0044] The flocculant is polyacrylamide, molecular weight ≥ 17 million, white granular solid. 20-30% of the underflow (neutralized slurry) is used for circulating slurry, and 70-80% is transported to the tailings tank and mixed with the tailings slurry to be transported to the tailings pond for storage.

[0045] The pH of the acidic wastewater in step (1) is 3.0-4.5, the main ion concentrations are TFe 200-500 mg / L, Cu 20-40 mg / L, Mn 80-150 mg / L, and Mg 100-150 mg / L; SO4 2- ~ is 3000~6000mg / L; the pH of the alkaline wastewater is 10.5~11.8, and the COD is 600~1200mg / L. The main ion concentration S2O3 2- ~4000-7000mg / L, S x 2- 40~120mg / L, Na + It is 600-1000mg / L.

[0046] In the step (2), the dosage of the catalyst and the oxidizing agent is 0.2 to 0.3 kg / m 3 Total water, oxidant 1.0~1.2kg / m 3 Total water.

[0047] The mass ratio of carbide slag to lime in step (3) is (0.2-0.5):1, and the amount of carbide slag and lime is 4.5-5.0 kg / m 3 Acidic water.

[0048] The amount of the flocculant used in step (4) is 2.8 to 3.5 g / m 3 Total water, flocculation particle sedimentation rate is 20-50cm / min, and the transmittance of the supernatant is ≥95%; the overflow water properties are pH 6.5-7.5, COD <60mg / L, SS <80mg / L, NH3-H <2mg / L, sulfide <1.0mg / L, Cu <0.5mg / L, Ca200-300mg / L.

[0049] Example 1

[0050] (1) The acidic water, overflow water from copper and sulfur concentrates, and high-alkali and high-residue copper-molybdenum separation wastewater are fed into a mixing tank, with the main ion concentrations of TFe being 200 mg / L, Cu 20 mg / L, Mn 80 mg / L, and Mg 100 mg / L; SO4 2- The pH of the alkaline wastewater is 11.8, and the COD is 1200 mg / L. The main ion concentration is S2O3 2- 7000mg / L,S x 2- 40mg / L, Na + The pH in the tank was controlled to 4.5 by a pH controller, and the catalyst and oxidant were added and stirred for 3 minutes at a stirring intensity of 25 r / min.

[0051] (2) The overflow water in the mixing tank is fed into the first reaction tank by gravity or pump, and a certain amount of compressed air is introduced and fully stirred to make it react completely. The amount of compressed air is 10m 3 / min, stirring time is 20min, and stirring intensity is 30r / min.

[0052] The catalyst contains a large number of functional groups such as hydroxyl, sulfhydryl, carboxyl, and amino groups. The functional groups are obtained by culturing, separating, and drying a 100:90 ratio of thiobacillus liquid with ferrous chloride and ferrous nitrate. The oxidizing agent is mainly a 30% hydrogen peroxide (H2O2) solution, and the catalyst is 0.3kg / m 3 Total water, oxidant 1.2kg / m 3 Total water.

[0053] (3) The overflow water in the first reaction tank is fed to the second reaction tank by gravity or pumping, and the carbide slag and lime are prepared into an emulsion state, the mass ratio of carbide slag and lime is 0.2:1, and the amount of carbide slag and lime is 4.5kg / m 3 Acidic water is fed into the second reaction tank by a pump, and the pH of the liquid is adjusted to 7.5 by a pH controller, the stirring time is 20 minutes, and the stirring intensity is 40r / min;

[0054] (4) The overflow water in the second reaction tank is fed to the degassing tank by gravity or pump. During the process of gravity feeding into the high-efficiency thickener, a certain amount of flocculant polyacrylamide is fed by a metering pump, with a molecular weight of ≥17 million and a flocculant dosage of 3.5 g / m 3The total water enters the high-efficiency thickener for flocculation reaction for 2 minutes, precipitation and concentration, and the overflow of the thickener, i.e. the clarified liquid, is the qualified discharge water, which can be pumped to the high-level water pool for use in mineral processing production, or discharged from the outlet; 30% of the bottom flow (neutralized mud) of the sedimentation tank is used as circulating slurry to return to the second reaction tank, the rest is discharged and stored, and 70% is transported to the tailings tank and mixed with the tailings slurry and transported to the tailings pond for storage.

[0055] After the above steps, the sedimentation rate of flocculated particles is 50cm / min, and the transmittance of the supernatant is ≥95%; the properties of the overflow water are as follows: pH 7.5, COD<60mg / L, SS<80mg / L, NH3-H<2mg / L, sulfide<1.0mg / L, Cu<0.5mg / L, Ca200-300mg / L.

[0056] Example 2

[0057] (1) The acidic water, overflow water from copper and sulfur concentrates, and high-alkali and high-residue copper-molybdenum separation wastewater are fed into a mixing tank, with the main ion concentrations of TFe being 250 mg / L, Cu 30 mg / L, Mn 100 mg / L, and Mg 120 mg / L; SO4 2- The pH of the alkaline wastewater is 11, and the COD is 1000 mg / L. The main ion concentration is S2O3 2- 4500mg / L,S x 2- 80mg / L, Na + The pH in the tank was controlled to 4 by a pH controller, and the catalyst and oxidant were added and stirred for 5 minutes at a stirring intensity of 40 r / min.

[0058] (2) The overflow water in the mixing tank is fed to the first reaction tank by gravity or pump, and a certain amount of compressed air is introduced and fully stirred to make it react completely. The amount of compressed air is 8m 3 / min, stirring time is 18min, and stirring intensity is 28r / min.

[0059] The catalyst contains a large number of functional groups such as hydroxyl, sulfhydryl, carboxyl, and amino. The functional groups are obtained by culturing, separating, and drying thiobacillus liquid with ferrous chloride and ferrous nitrate in a ratio of 100:90. The oxidizing agent is mainly a 29% hydrogen peroxide (H2O2) solution, and the catalyst is 0.2kg / m 3 Total water, oxidant 1.1kg / m 3 Total water.

[0060] (3) The overflow water in the first reaction tank is fed to the second reaction tank by gravity or pumping, and the carbide slag and lime are prepared into an emulsion state, the mass ratio of carbide slag and lime is 0.3:1, and the amount of carbide slag and lime is 4.8 kg / m 3 Acidic water is fed into the second reaction tank by a pump, and the pH of the liquid is adjusted to 8 by a pH controller, the stirring time is 20 minutes, and the stirring intensity is 35 r / min;

[0061] (4) The overflow water in the second reaction tank is fed to the degassing tank by gravity or pump. During the process of gravity feeding into the high-efficiency thickener, a certain amount of flocculant polyacrylamide is fed by a metering pump, with a molecular weight of ≥17 million and a flocculant dosage of 3.0 g / m 3 The total water enters the high-efficiency thickener for flocculation reaction for 1 minute, precipitation and concentration, and the overflow of the thickener, i.e. the clarified liquid, is the qualified discharge water, which can be pumped to a high-level water tank for use in mineral processing production, or discharged from the outlet; 25% of the bottom flow of the sedimentation tank (neutralized mud) is used as circulating slurry to return to the second reaction tank, the rest is discharged and stored, and 75% is transported for external treatment.

[0062] Example 3

[0063] (1) The acidic water, overflow water from copper and sulfur concentrates, and high-alkali and high-residue copper-molybdenum separation wastewater are fed into a mixing tank, and the main ion concentrations are TFe 400 mg / L, Cu 40 mg / L, Mn 150 mg / L, and Mg 150 mg / L; SO4 2- The pH of the alkaline wastewater is 10.5, and the COD is 1200 mg / L. The main ion concentration is S2O3 2- 6000mg / L,S x 2- 100mg / L, Na + The pH in the tank was controlled to 4.5 by a pH controller, and the catalyst and oxidant were added and stirred for 4.5 minutes at a stirring intensity of 30 r / min.

[0064] (2) The overflow water in the mixing tank is fed into the first reaction tank by gravity or pump, and a certain amount of compressed air is introduced and fully stirred to make it react completely. The amount of compressed air is 6m 3 / min, stirring time is 20min, and stirring intensity is 30r / min.

[0065] The catalyst contains a large number of functional groups such as hydroxyl, sulfhydryl, carboxyl, and amino. The functional groups are obtained by culturing, separating, and drying thiobacillus liquid with ferrous chloride and ferrous nitrate in a ratio of 100:90. The oxidizing agent is mainly a 27.5% hydrogen peroxide (H2O2) solution, and the catalyst is 0.22kg / m3 Total water, oxidant 1.15kg / m 3 Total water.

[0066] (3) The overflow water in the first reaction tank is fed to the second reaction tank by gravity or pumping, and the carbide slag and lime are prepared into an emulsion state, the mass ratio of carbide slag and lime is 0.5:1, and the amount of carbide slag and lime is 5kg / m 3 Acidic water is fed into the second reaction tank by a pump, and the pH of the liquid is adjusted to 8.5 by a pH controller, the stirring time is 15 minutes, and the stirring intensity is 25 r / min;

[0067] (4) The overflow water in the second reaction tank is fed to the degassing tank by gravity or pump, and the flocculant polyacrylamide is fed by a metering pump, with a molecular weight of ≥17 million and a flocculant dosage of 3.5 g / m 3 Total water, reaction time is 2min. The overflow of the flocculation tank is fed into the high-efficiency thickener for sedimentation and concentration. The overflow of the thickener, i.e. the clarified liquid, is the qualified discharge water, which can be pumped to the high-level water tank for use in mineral processing production, or discharged from the outlet; 22% of the bottom flow of the sedimentation tank (neutralized mud) is used as circulating slurry to return to the second reaction tank, the rest is discharged and stored, and 78% is transported to the tailings tank and mixed with the tailings slurry to be transported to the tailings pond for storage.

[0068] Example 4

[0069] (1) The acidic water, overflow water from copper and sulfur concentrates, and high-alkali and high-residue copper-molybdenum separation wastewater are fed into a mixing tank, with the main ion concentrations of TFe being 450 mg / L, Cu 38 mg / L, Mn 150 mg / L, and Mg 150 mg / L; SO4 2- The pH of the alkaline wastewater is 11.0, and the COD is 850 mg / L. The main ion concentration is S2O3 2- 4750mg / L,S x 2- 115mg / L, Na + The pH in the tank was controlled to 4.0 using a pH controller, and the catalyst and oxidant were added and stirred for 3 minutes at a stirring intensity of 35 r / min.

[0070] (2) The overflow water in the mixing tank is fed into the first reaction tank by gravity or pump, and a certain amount of compressed air is introduced and fully stirred to make it react completely. The amount of compressed air is 5m 3 / min, stirring time is 18min, and stirring intensity is 28r / min.

[0071] The catalyst contains a large number of functional groups such as hydroxyl, sulfhydryl, carboxyl, and amino. The functional groups are obtained by culturing, separating, and drying thiobacillus liquid with ferrous chloride and ferrous nitrate in a ratio of 100:90. The oxidizing agent is mainly a 29% hydrogen peroxide (H2O2) solution, and the catalyst is 0.30kg / m 3 Total water, oxidant 1.1kg / m 3 Total water.

[0072] (3) The overflow water in the first reaction tank is fed to the second reaction tank by gravity or pumping, and the carbide slag and lime are prepared into an emulsion state, the mass ratio of carbide slag and lime is 0.45:1, and the amount of carbide slag and lime is 4.85 kg / m 3 Acidic water is fed into the second reaction tank by a pump, and the pH of the liquid is adjusted to 8 by a pH controller, the stirring time is 16 minutes, and the stirring intensity is 28 r / min;

[0073] (4) The overflow water in the second reaction tank is fed to the degassing tank by gravity or pump, and the flocculant polyacrylamide is fed by a metering pump, with a molecular weight of ≥17 million and a flocculant dosage of 3.2 g / m 3 Total water, reaction time is 1.5min. The overflow of the flocculation tank is fed into the high-efficiency thickener for sedimentation and concentration. The overflow of the thickener, i.e., the clarified liquid, is the qualified discharge water, which can be pumped to the high-level water tank for use in mineral processing production, or discharged from the outlet; 26% of the bottom flow of the sedimentation tank (neutralized mud) is used as circulating slurry to return to the second reaction tank, the rest is discharged and stored, and 74% is transported for external treatment.

[0074] Comparative Example 1

[0075] The method for treating high-alkali and high-residue copper-molybdenum separation wastewater provided in this comparative example refers to Example 1, with the only difference being that in step (2), the catalyst is Fe3O4.

[0076] Comparative Example 2

[0077] The method for treating high-alkali and high-residue copper-molybdenum separation wastewater provided in this comparative example refers to Example 1, except that in step (2), the oxidant is sodium hypochlorite.

[0078] Test Example 1

[0079] In the high-alkali and high-residue copper-molybdenum separation wastewater treatment method in Examples 1 to 4 and Comparative Examples 1 to 2, the properties of the overflow water are shown in Table 1.

[0080] Table 1 Unit: mg / L

[0081]

[0082] Although the present invention has been illustrated and described with specific embodiments, it should be appreciated that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Those skilled in the art should understand that the technical solutions described in the above embodiments may be modified, or some or all of the technical features thereof may be replaced by equivalents without departing from the spirit and scope of the present invention. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention. Therefore, this means that all such replacements and modifications within the scope of the present invention are included in the appended claims.

Claims

1. A method for treating high-alkali and high-residue copper-molybdenum separation wastewater, characterized in that: The processing method specifically comprises the following steps: S1) feeding the high-alkali high-residue copper-molybdenum separation wastewater and the acidic wastewater to be treated into a mixing tank, adjusting the pH value, and then adding a catalyst and an oxidant to stir evenly for standby use; S2) feeding the overflow water in the mixing tank after the treatment in S1) into the first reaction tank by gravity or pump, and simultaneously introducing a certain amount of compressed air and stirring sufficiently to make it react completely; S3) feeding the overflow water in the first reaction tank after the treatment in S2) into the second reaction tank by gravity or pump, adding a pH adjuster to adjust the pH value, and simultaneously introducing a certain amount of compressed air and stirring sufficiently to make the reaction complete; S4) The overflow water in the second reaction tank treated in S3) is fed to the degassing tank by gravity or pump. During the process of gravity feeding to the high-efficiency thickener, a certain amount of flocculant is fed by a metering pump. The flocculation reaction in the high-efficiency thickener is 1 to 2 minutes, and the precipitate and concentrate to obtain clarified liquid and sedimentation tank bottom flow. The clarified liquid is the qualified discharge water.

2. The processing method according to claim 1, characterized in that: The acidic wastewater in S1) is the acidic wastewater from the waste rock dump in the mining area, the pH of the wastewater is 3.0-4.5, and the ion concentration of TFe is 200-500 mg / L, Cu is 20-40 mg / L, Mn is 80-150 mg / L, and Mg is 100-150 mg / L; SO4 2- 3000~6000mg / L; The pH of the high-alkali high-residue copper-molybdenum separation wastewater is 10.5-11.8, and the COD is 600-1200 mg / L. 2- Ion concentration is 4000-7000mg / L, S x 2- 40-120mg / L, Na + 600-1000mg / L; The dosage of the catalyst and oxidant is: catalyst 0.2-0.3 kg / m 3 Total water, oxidant 1.0~1.2kg / m 3 Total water; The pH value is 3.5-4.

5. After adding the catalyst and the oxidant, stir and mix for 3-5 minutes with a stirring intensity of 25r / min-40r / min.

3. The processing method according to claim 2, characterized in that: The catalyst is a metabolite of a composite functional bacterial community mainly composed of Thiobacillus, and contains a large number of hydroxyl, sulfhydryl, carboxyl or amino functional groups; The functional group is obtained by culturing, separating and drying a thiobacillus solution with ferrous chloride and ferrous nitrate in a ratio of 100:90; The oxidant is a 27.5%-30% hydrogen peroxide solution.

4. The processing method according to claim 1, characterized in that: The amount of compressed air in S2) is 5 to 10 m 3 / min, stirring time is 15-20min, and stirring intensity is 25r / min-30r / min.

5. The processing method according to claim 1, characterized in that: The pH in S3) is 7.5-8.5, and the amount of pH regulator is 4.5-5.0 kg / m 3 Acidic water; compressed air volume is 5-10m 3 / min, stirring time is 15-20min, and stirring intensity is 25r / min-30r / min.

6. The processing method according to claim 5, characterized in that: The pH regulator is a mixture of carbide slag and lime in a mass ratio of (0.2-0.5):

1.

7. The processing method according to claim 1, characterized in that: The amount of flocculant in S4) is 2.8-3.5 g / m 3 Total water, flocculation particle settling rate is 20-50cm / min, compressed air volume is 5-10m 3 / min, stirring time is 15-20min, and stirring intensity is 25r / min-30r / min.

8. The processing method according to claim 7, characterized in that: The flocculant is polyacrylamide with a molecular weight of ≥17 million.

9. The processing method according to claim 1, characterized in that: The clear liquid obtained by the treatment method has a light transmittance of ≥95%, a pH of 6.5-7.5, COD<60mg / L, SS<80mg / L, NH3-H<2mg / L, sulfide<1.0mg / L, Cu<0.5mg / L, and Ca200-300mg / L.

10. The processing method according to claim 1, characterized in that: 20-30% of the bottom slag of the sedimentation tank is used as circulating slurry to return to the second reaction tank, and 70-80% is transported out for treatment.

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