Method for treating mine acid wastewater with complex components

Abstract

The invention belongs to the technical field of wastewater treatment, and particularly discloses a treatment method for complex-component mine acid wastewater. The method comprises the following steps: introducing wastewater into a primary mixing reaction tank, and respectively adding an alkaline agent, powdered zeolite and a heavy metal capturing agent to adjust the pH value and remove organic nitrogen and NH3-N to form a heavy metal chelate precipitate; pressurizing effluent in the first-stage mixing reaction tank to a first-stage efficient cyclone water purifier, carrying out solid-liquid separation, and introducing the wastewater into an efficient denitrification filter to adsorb organic nitrogen; introducing the filtrate in the efficient denitrification filter into a secondary mixing reaction tank, and then respectively adding a heavy metal capturing agent, a defluorination agent and NaClO; pressurizing the wastewater in the second-stage mixing reaction tank to a second-stage efficient cyclone water purifier, then introducing the wastewater into an efficient manganese removal filter, then introducing filtrate into a clean water tank, and finally calculating the removal rate n of each pollutant. The method has the characteristics of high treatment efficiency, simplicity and convenience in operation, stability in operation and low cost.

Description

Technical Field

[0001] The present invention belongs to the technical field of wastewater treatment, and particularly relates to a method for treating complex-component mine acid wastewater with high treatment efficiency, simple operation, stable operation and low cost. Background Technique

[0002] China is a major mining country. With the rapid development of industry, the demand for mineral resources has been increasing year by year. During the mining and beneficiation process of mines, sulfides in ore bodies, tailings and waste rocks are oxidized and dissolved in water, bringing acidity, which causes heavy metal elements such as copper, lead, zinc, and cadmium to dissolve in the wastewater to form heavy metal wastewater; at the same time, the use of beneficiation reagents and explosives significantly increases the total nitrogen content in the wastewater; in addition, the wastewater also contains dissolved solid substances and other pollutants such as calcium, magnesium, and COD. Therefore, a large amount of acid wastewater generated during the mining and beneficiation process of mines is not only often complex in composition, but also usually has a pH value lower than 4, and also contains various heavy metals (lead, manganese, arsenic, cadmium, chromium, copper, iron, etc.), nitrogen, phosphorus, COD, calcium and magnesium and other components. If the mine acid wastewater is not properly treated, it will pollute water bodies and soil after being discharged, and the heavy metals therein will accumulate in crops, fish and shrimp, and ultimately threaten human health through the food chain. Therefore, it is urgent to take appropriate measures to treat mine acid wastewater, which is crucial for the ecological environment and human health.

[0003] Due to the large fluctuations in the water quality and quantity of mine acid wastewater with seasons, the treatment difficulty is relatively large and the process requirements are high. Currently, it is mainly treated by physical methods, chemical methods and biological methods.

[0004] In physical methods, the adsorption method uses porous adsorption materials to remove heavy metals. Heavy metal ions are adsorbed in the surface voids and separated from the wastewater by gravity sedimentation or external force. Physical adsorption materials can be activated carbon, diatomite, zeolite, activated alumina, etc., while chemical adsorption materials include substances such as resin and chitosan. Although there are many types of adsorption materials, wide sources, and simple adsorption process operations, due to the complex composition, high acidity, and unstable water volume of mine acidic wastewater, the adsorption materials are limited in practical engineering applications. At the same time, if the materials after adsorption are not properly treated, it will cause secondary pollution. In addition, in physical methods, there is also the ion exchange method, which uses specific functional groups contained in the resin to complex or chelate with heavy metal ions, and removes heavy metals by replacing the original cations on the resin. The ion exchange method is suitable for low-concentration heavy metal wastewater. If the wastewater concentration is high, problems such as fast adsorption saturation, frequent backwashing, and frequent resin replacement will occur. In addition, the membrane separation method is also a commonly used physical method, which uses pressure to achieve separation. Through membrane separation treatment, the produced fresh water is recycled for production, and the concentrated water enters the subsequent treatment system to reduce the amount of water that enterprises need to treat through concentration. However, due to the high cost of the membrane, and it is easily contaminated and blocked by organic matter, calcium, and magnesium ions, and the membrane elements need to be cleaned and replaced regularly, the membrane technology is limited in the engineering application of mine acidic wastewater.

[0005] Chemical methods are divided into chemical precipitation and chemical oxidation methods. The precipitation method is to add chemical agents to the wastewater to form insoluble precipitates after reacting with heavy metal ions. The precipitation method is further divided into the neutralization method and the sulfidation method. Among them, the neutralization method is to add alkaline agents to the wastewater to generate hydroxide precipitates with heavy metal ions while neutralizing the pH. The sulfidation method is to add sulfur-containing chemical agents to make sulfide ions react with heavy metal ions to produce precipitates. Although the removal rate is high, the generated hydrogen sulfide gas is toxic and easy to cause pollution. The chemical oxidation method is a method that uses oxidants to oxidize metal ions such as iron and manganese, and then removes them in the form of iron hydroxide and manganese dioxide precipitates.

[0006] The biological method requires adding sulfate-reducing bacteria to the wastewater. Utilizing the reducibility of sulfates, the sulfate radicals in the wastewater are reduced to sulfides. At the same time, microorganisms have natural adsorption of heavy metal ions or the metabolites of microorganisms can form flocs with heavy metal ions to remove them. However, the biological method may cause secondary pollution, and microorganisms are relatively sensitive to environmental conditions such as temperature and oxygen, and the pH value of the wastewater cannot be too low, so it has certain limitations.

[0007] In summary, for mine acidic wastewater with complex components, the current treatment technologies have their own advantages and limitations, and it is difficult to apply them to practical engineering only through a single technology or process. Therefore, there is an urgent need for a treatment method that can flexibly combine processes according to the actual water quality and water volume conditions, achieving high treatment efficiency, simple operation, stable operation, and low cost. Summary of the Invention

[0008] In view of the deficiencies of the prior art, the present invention provides a method for treating acidic wastewater from mines with complex components, which has high treatment efficiency, is easy to operate, has stable operation, and low cost.

[0009] The method for treating acidic wastewater from mines with complex components of the present invention is realized as follows: It includes chelating precipitation, separating and denitrifying, defluorination and nitrogen removal, and subsequent treatment steps. The specific content is as follows: A. Chelating precipitation: Introduce the acidic wastewater from mines with complex components into the first-stage mixing reaction tank, and then add an alkaline agent, powdered zeolite, and a heavy metal scavenger respectively for mechanical stirring to adjust the pH value and remove organic nitrogen and NH 3 -N, and form a heavy metal chelate precipitate; B. Separating and denitrifying: Pressurize the effluent in the first-stage mixing reaction tank to a first-stage high-efficiency hydrocyclone water purifier. After solid-liquid separation, use the residual pressure to introduce the effluent into a high-efficiency denitrification filter to adsorb organic nitrogen; C. Defluorination and nitrogen removal: Introduce the effluent in the high-efficiency denitrification filter into the second-stage mixing reaction tank, and then add a heavy metal scavenger, a defluorination agent, and NaClO respectively for mechanical stirring to remove fluorine, NH 3 -N while oxidizing the residual Mn in the water; D. Subsequent treatment: Pressurize the effluent in the second-stage mixing reaction tank to a second-stage high-efficiency hydrocyclone water purifier, then use the residual pressure to introduce it into a high-efficiency manganese removal filter, and then use the residual pressure to introduce the filtrate into a clear water tank. Finally, calculate the removal rate n of each pollutant.

[0010] Further, in step A, the alkaline agent is any one of NaOH, quicklime, and slaked lime, and the powdered zeolite is 80-mesh particles; the dosage is added when the pH of the acidic wastewater in the first-stage mixing reaction tank is lower than 7, and the dosage is reduced when the pH is greater than 8.

[0011] Further, in step A, the pH value of the acidic wastewater in the first-stage mixing reaction tank is adjusted to 7.0 - 9.5, and mechanical stirring is continuously carried out at the same time.

[0012] Further, in step B, the treatment capacities of the first-stage high-efficiency hydrocyclone water purifier and the high-efficiency denitrification filter are 35 m 3 / h, and the high-efficiency denitrification filter is provided with powdered zeolite or a denitrification resin containing a sulfur group as a filter material.

[0013] Further, in steps A and C, the heavy metal scavenger is any one or any combination of polyaluminum chloride, silicate, carbonate, and activated carbon.

[0014] Further, in the step C, mechanical stirring is continuously carried out, and the defluorination agent is any one or any combination of lime, calcium chloride, polyaluminum oxide, activated carbon, polyaluminum chloride and polyferric sulfate.

[0015] Further, in the step C, the configured mass concentration of NaClO does not exceed 10%.

[0016] Further, in the step D, the treatment capacity of the secondary high-efficiency cyclone water purifier and the high-efficiency manganese removal filter is 35 m 3 / h, and the main component of the filter material in the high-efficiency manganese removal filter is natural manganese sand filter material with a manganese dioxide content of 35% - 45%.

[0017] Further, in the step D, the removal rate n of each pollutant is: In the formula: n x is the removal rate of pollutant x, and x is the type of pollutant / over-standard index including Cu, Zn, Ni, Cd, Fe, Mn, TN, COD, SS, F-.

[0018] Further, the sludge of the primary high-efficiency cyclone water purifier and the secondary high-efficiency cyclone water purifier is discharged into the sludge pool; the backwash water of the high-efficiency manganese removal filter and the analytical waste liquid of the high-efficiency denitrification filter are discharged into the backwash pool; the supernatant in the sludge pool and the backwash pool returns to the primary mixing reaction pool.

[0019] Compared with the prior art, the beneficial effects of the present invention are: 1. In view of the strong acidity of the mine acid wastewater, as well as the chemical oxygen demand, total nitrogen, fluoride, and various toxic and harmful heavy metals such as copper, zinc, cadmium, iron, manganese, and nickel, and the fact that the suspended solid content exceeds the standard, the present invention first adds alkaline agents to neutralize the strong acidity, then adds heavy metal capturers to co-precipitate heavy metal hydroxides, and adds powdered zeolite, combines with a high-efficiency denitrification filter to adsorb and remove organic nitrogen, and at the same time screens defluorination agents to specifically remove fluoride ions; through a multi-process combination of staged chelation precipitation, denitrification, and fluorine and nitrogen removal, it efficiently and synergistically synchronously removes heavy metals (such as Cu, Pb, Zn, Cd, etc.), fluorine, organic nitrogen / NH 3 -N and Mn and other pollutants, overcomes the limitation that it is difficult for existing single technologies to deal with complex components, and significantly improves the comprehensive treatment efficiency.

[0020] 2. The present invention selects a high-efficiency cyclone water purifier for solid-liquid separation; for ammonia nitrogen in acidic wastewater, it is oxidized to nitrogen and removed by breakpoint chlorination using the strong oxidizing property of NaClO; for the prominent situation of excessive heavy metal manganese, a high-efficiency manganese removal filter is set up to remove it with manganese sand filter media, so that not only can the corresponding pollutants in the wastewater be removed at low cost, but also by removing different pollutants step by step, the solid waste discharge and the dosage of chemicals can be reduced.

[0021] 3. The present invention can flexibly adjust the chemical dosage (such as multi-stage dosing of heavy metal capturer) and filter media combination (powdered zeolite and resin can be optionally matched) according to water quality and water volume, so as to adapt to the seasonal fluctuation characteristics of mine wastewater and ensure the operation stability. And through the oxidation of residual Mn by NaClO and secondary manganese removal filtration (natural manganese sand filter media), combined with multi-stage solid-liquid separation (cyclone water purifier), it can ensure that the final effluent meets the reuse or discharge standards.

[0022] 4. The present invention adopts a chelating precipitation process (A / C step) without sulfidation method, which can avoid the hidden danger of generating toxic H 2 S gas in the traditional sulfidation method; and through centralized sludge treatment and reuse of backwash water of filter media, the solid waste discharge and the possibility of secondary pollution are reduced.

[0023] 5. The present invention selects low-cost filter media such as powdered zeolite and natural manganese sand, which significantly reduces the equipment investment and maintenance cost compared with membrane separation technology; moreover, the residual pressure of the high-efficiency cyclone water purifier is used to drive the subsequent filtration unit, which can reduce the additional pressurization energy consumption; and the modular equipment combination (cyclone + filter) can shorten the treatment process and improve the operation convenience.

[0024] 6. The sludge discharged from the high-efficiency cyclone water purifier and the backwash water drained from the high-efficiency manganese removal filter of the present invention can respectively enter the sludge tank and the backwash tank, the supernatant returns to the first-stage mixing reaction tank, the filtrate after the bottom sludge is pressure-filtered returns to the first-stage mixing reaction tank, and the mud cake can be reused or disposed according to its properties, realizing the reuse of chemicals and water.

[0025] In summary, the present invention has the characteristics of high treatment efficiency, simple operation, stable operation and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is the process flow chart of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0027] The following further describes the present invention in conjunction with the drawings and embodiments, but the present invention is not limited in any way. Any changes or improvements made based on the teachings of the present invention fall within the protection scope of the present invention.

[0028] Such as Figure 1As shown in the figure, the method for treating acidic wastewater from mines with complex components of the present invention includes chelating precipitation, separating and denitrifying, defluorinating and nitrogen removal, and subsequent treatment steps. The specific contents are as follows: A. Chelating precipitation: Introduce the acidic wastewater from mines with complex components into the first-stage mixing reaction tank, and then add alkaline agents, powdered zeolite, and heavy metal capturers respectively for mechanical stirring to adjust the pH value and remove organic nitrogen and NH 3 -N, and form heavy metal chelate precipitation; B. Separating and denitrifying: Pressurize the effluent in the first-stage mixing reaction tank to the first-stage high-efficiency hydrocyclone water purifier. After solid-liquid separation, use the remaining pressure to introduce the effluent into the high-efficiency denitrification filter to adsorb organic nitrogen; C. Defluorinating and nitrogen removal: Introduce the effluent in the high-efficiency denitrification filter into the second-stage mixing reaction tank, and then add heavy metal capturers, defluorinating agents, and NaClO respectively for mechanical stirring to remove fluorine, NH 3 -N while oxidizing the residual Mn in the water; D. Subsequent treatment: Pressurize the effluent in the second-stage mixing reaction tank to the second-stage high-efficiency hydrocyclone water purifier, then use the remaining pressure to introduce it into the high-efficiency manganese removal filter, and then use the remaining pressure to introduce the filtrate into the clear water tank. Finally, calculate the removal rate n of each pollutant.

[0029] In the step A, the alkaline agent is any one of NaOH, quicklime, and slaked lime, and the powdered zeolite is 80-mesh particles; the dosage is added when the pH of the acidic wastewater in the first-stage mixing reaction tank is lower than 7, and the dosage is reduced when the pH is greater than 8.

[0030] In the step A, the pH value of the acidic wastewater in the first-stage mixing reaction tank is adjusted to 7.0 - 9.5, and mechanical stirring is continuously carried out at the same time.

[0031] In the step B, the treatment capacity of the first-stage high-efficiency hydrocyclone water purifier and the high-efficiency denitrification filter is 35m 3 / h, and the high-efficiency denitrification filter is provided with powdered zeolite or denitrification resin containing sulfur groups as filter materials.

[0032] In the steps A and C, the heavy metal capturer is any one or any combination of polyaluminum chloride, silicate, carbonate, and activated carbon.

[0033] In the step C, mechanical stirring is continuously carried out, and the defluorinating agent is any one or any combination of lime, calcium chloride, polyaluminum oxide, activated carbon, polyaluminum chloride, and polyferric sulfate.

[0034] In the step C, the configured mass concentration of NaClO does not exceed 10%.

[0035] In the step D, the treatment capacity of the second-stage high-efficiency hydrocyclone water purifier and the high-efficiency manganese removal filter is 35m 3 / h, the filter material in the high-efficiency manganese removal filter is mainly natural manganese sand filter material with a manganese dioxide content of 35% - 45%.

[0036] In the said D step, the removal rate n of each pollutant is: In the formula: n x is the removal rate of pollutant x, and x is the type of pollutant / over-standard index including Cu, Zn, Ni, Cd, Fe, Mn, TN, COD, SS, F-.

[0037] 0 - 240 L / h of polyaluminum chloride or polyacrylamide is added to the wastewater of the said primary high-efficiency cyclone water purifier and / or secondary high-efficiency cyclone water purifier.

[0038] The sludge of the said primary high-efficiency cyclone water purifier and secondary high-efficiency cyclone water purifier is discharged into the sludge pool; the backwash water of the high-efficiency manganese removal filter and the analytical waste liquid of the high-efficiency denitrification filter are discharged into the backwash pool; the supernatant in the sludge pool and backwash pool returns to the primary mixing reaction pool. Example 1

[0039] S100: Import the complex-component mine acid wastewater of a certain mine into the primary 3-cell mixing reaction pool, and then add the prepared NaOH with a mass concentration of 30% (dosage 30 m 3 / h), powdered zeolite with a particle size of 80 mesh, and polyaluminum chloride, and carry out mechanical stirring to adjust the pH value of the wastewater to 9.5, so as to remove the organic nitrogen and NH 3 -N in the wastewater, and form heavy metal chelate precipitates.

[0040] S200: Pressurize the effluent in the primary mixing reaction pool with a pump to the primary high-efficiency cyclone water purifier (treatment capacity is 35 m 3 / h, add 30 L / h of polyaluminum chloride), after solid-liquid separation, use the residual pressure to import the effluent into the high-efficiency denitrification filter filled with denitrification resin (treatment capacity is 35 m 3 / h) to adsorb organic nitrogen.

[0041] S300: Import the effluent in the high-efficiency denitrification filter into the secondary mixing reaction pool by using the residual pressure, and then add polyaluminum chloride, lime, and NaClO with a mass concentration of 10% respectively to remove fluorine and NH 3 -N while oxidizing the residual Mn in the water.

[0042] S400: Pressurize the effluent in the secondary mixing reaction pool with a lift pump to the secondary high-efficiency cyclone water purifier (add 5 L / h of polyaluminum chloride), and then use the residual pressure to import it into the high-efficiency manganese removal filter containing natural manganese sand filter material (treatment capacity is 35 m 3 / h), and then the effluent is introduced into the clean water tank using the residual pressure. Samples of the original mine acidic wastewater and the water in the clean water tank are entrusted to a third party for inspection. Finally, the removal rate n of each pollutant is calculated. The specific results are shown in Table 1.

[0043] In the formula: n x is the removal rate of pollutant x, and x is the type of pollutant / over-standard index including Cu, Zn, Ni, Cd, Fe, Mn, TN, COD, SS, F-.

[0044] S500: The sludge of the primary high-efficiency cyclone water purifier and the secondary high-efficiency cyclone water purifier is discharged into the sludge tank. The backwash water of the high-efficiency manganese removal filter and the analytical waste liquid of the high-efficiency denitrification filter are discharged into the backwash tank. The supernatant in the sludge tank and the backwash tank is returned to the primary mixing reaction tank.

[0045] Table 1 Statistical table of the removal rates of various pollutants in mine acidic heavy metal wastewater

[0046] It can be seen from the statistics in Table 1 that for the treatment of mine acidic wastewater with complex components in this embodiment, multiple heavy metal ions such as copper, zinc, cadmium, iron, and manganese can be efficiently removed, and the highest removal rate reaches 97.73%. At the same time, it also has a relatively high removal rate for total nitrogen, chemical oxygen demand, and fluoride. Example 2

[0047] S100: Introduce the mine acidic wastewater with complex components from a certain mine into the primary three-compartment mixing reaction tank, and then add quicklime (mass concentration of 20%), powdered zeolite with a particle size of 80 mesh, and a mineral water-soluble compound (aluminum silicate solution with a mass concentration of 15%) respectively to adjust the pH value of the wastewater to 8.0, so as to remove the organic nitrogen and NH 3 -N in the wastewater and form heavy metal chelate precipitates.

[0048] S200: Use a pump to pressurize the effluent in the primary mixing reaction tank to a primary high-efficiency cyclone water purifier (treatment capacity of 35 m 3 / h, adding 200 L / h of polyaluminum chloride). After solid-liquid separation, use the residual pressure to introduce the effluent into a high-efficiency denitrification filter filled with 80-mesh powdered zeolite (treatment capacity of 35 m 3 / h) to adsorb organic nitrogen.

[0049] S300: Use the residual pressure to introduce the effluent in the high-efficiency denitrification filter into the secondary mixing reaction tank, and then add aluminum silicate, calcium chloride, and NaClO with a mass concentration of 9% respectively to remove fluorine and NH 3 -N while oxidizing the residual Mn in the water.

[0050] S400: Pressurize the effluent in the secondary mixing reaction tank to the secondary high-efficiency cyclone water purifier (adding 50 L / h of polyaluminum chloride) with a lift pump, and then introduce it into the high-efficiency manganese removal filter containing natural manganese sand filter media (treatment capacity is 35 m 3 / h) using the residual pressure. Subsequently, introduce the effluent into the clear water tank using the residual pressure, and send the original mine acidic wastewater and the water samples in the clear water tank to a third party for inspection. Finally, calculate the removal rate n of each pollutant. The specific results are shown in Table 1.

[0051] In the formula: n x is the removal rate of pollutant x, and x is the type of pollutant / over-standard index including Cu, Zn, Ni, Cd, Fe, Mn, TN, COD, SS, F-.

[0052] Table 2 Statistical table of the removal rates of various pollutants in mine acidic heavy metal wastewater

[0053] It can be seen from the statistics in Table 2 that for the treatment of mine acidic wastewater with complex components in this embodiment, multiple heavy metal ions such as copper, zinc, cadmium, iron, and manganese can be efficiently removed, and the highest removal rate reaches 95.12%. At the same time, it also has a relatively high removal rate for total nitrogen, chemical oxygen demand, and fluoride.

[0054] The above is only the preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, and all of them should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A method for treating acid mine wastewater with complex components, characterized by: It includes chelation precipitation, separation and denitrification, fluorine and nitrogen removal, and subsequent treatment steps. The specific contents are as follows: A. Chelating precipitation: The complex acid mine wastewater is introduced into the primary mixing reaction tank, and then alkaline reagents, powdered zeolite and heavy metal capture agents are added for mechanical stirring to adjust the pH value and remove organic nitrogen and NH3-N, and form heavy metal chelate precipitation; B. Separation and denitrification: The effluent from the primary mixed reaction tank is pressurized to the primary high-efficiency cyclone water purifier. After solid-liquid separation, the effluent is introduced into the high-efficiency denitrification filter using the residual pressure to adsorb organic nitrogen; C. Fluorine and nitrogen removal: The effluent from the high-efficiency denitrification filter is introduced into a secondary mixing reaction tank, and then heavy metal capture agent, defluorination agent and NaClO are added for mechanical stirring to remove fluorine and NH3-N while oxidizing the residual Mn in the water; D. Subsequent treatment: The effluent from the secondary mixed reaction tank is pressurized to the secondary high-efficiency cyclone water purifier, and then the residual pressure is used to introduce the high-efficiency manganese removal filter, and then the filtrate is introduced into the clean water tank using the residual pressure, and finally the removal rate n of each pollutant is calculated.

2. The method for treating acid mine wastewater with complex components according to claim 1, characterized in that: In the step A, the alkaline agent is any one of NaOH, quicklime and slaked lime, and the powdered zeolite is 80 mesh particles; when the pH of the acidic wastewater in the primary mixing reaction tank is lower than 7, the amount of the agent is added, and when the pH is greater than 8, the amount of the agent is reduced.

3. The method for treating complex acid mine wastewater according to claim 2, characterized in that: In the step A, the pH value of the acidic wastewater in the primary mixing reaction tank is adjusted to 7.0-9.5, and mechanical stirring is continuously performed.

4. The method for treating complex acid mine wastewater according to claim 1, characterized in that: In step B, the treatment capacity of the primary high-efficiency cyclone water purifier and the high-efficiency denitrification filter is 35m 3 / h, the high-efficiency denitrification filter is provided with powdered zeolite or denitrification resin containing sulfur group as filter material.

5. The method for treating complex acid mine wastewater according to claim 1, characterized in that: In the steps A and C, the heavy metal capture agent is any one or any combination of polyaluminium chloride, silicates, carbonates and activated carbon.

6. The method for treating complex acid mine wastewater according to claim 5, characterized in that: In the step C, mechanical stirring is continuously performed, and the defluorination agent is any one or any combination of lime, calcium chloride, polyaluminum oxide, activated carbon, polyaluminum chloride and polyferric sulfate.

7. The method for treating complex acid mine wastewater according to claim 6, characterized in that: In the step C, the configured mass concentration of NaClO does not exceed 10%.

8. The method for treating complex acid mine wastewater according to claim 1, characterized in that: In step D, the processing capacity of the secondary high-efficiency cyclone water purifier and the high-efficiency manganese removal filter is 35m 3 / h, the main component of the filter material in the high-efficiency manganese removal filter is natural manganese sand filter material with a manganese dioxide content of 35%~45%.

9. The method for treating complex acid mine wastewater according to claim 8, characterized in that: In the step D, the removal rate n of each pollutant is: Where: n x is the removal rate of pollutant x, where x is the type of pollutant / exceeding index including Cu, Zn, Ni, Cd, Fe, Mn, TN, COD, SS, and F-.

10. The method for treating complex acid mine drainage according to any one of claims 1 to 9, characterized in that: The sludge from the primary high-efficiency cyclone water purifier and the secondary high-efficiency cyclone water purifier is discharged into the sludge tank; the backwash water from the high-efficiency manganese removal filter and the analytical waste liquid from the high-efficiency denitrification filter are discharged into the backwash tank; the supernatant in the sludge tank and the backwash tank is returned to the primary mixing reaction tank.

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