An integrated on-site prevention and treatment system and method for acid mine drainage

Abstract

The application discloses an acid mine water producing site integrated prevention and treatment system and method, which comprises a pretreatment part, a treatment part, a solid-liquid separation part and an acid return prevention part. The outlet of the pretreatment part is connected with the inlet of the treatment part. The first outlet of the treatment part is connected with the inlet of the solid-liquid separation part. The second outlet of the treatment part and the liquid outlet of the solid-liquid separation part are both connected with the inlet of the acid return prevention part. The application has scientific principles and is easy to operate. The application can be used for treating acid mine water on site of a coal mine, so that the treated wastewater can meet the discharge standard and no longer return acid. The microbial electrolysis device can degrade sulfate ions in the wastewater more completely, so that energy can be saved, addition of pH adjusting reagents can be avoided, treatment cost can be reduced, secondary pollution can be avoided, fine sulfur ore can be obtained after treatment, and economic and environmental benefits can be achieved.

Description

Technical Field

[0001] This invention belongs to the field of environmental protection and treatment technology for coal mine wastewater, specifically relating to an integrated on-site prevention and control system and method for acidic mine water generation sites. Background Technology

[0002] The treatment process for acidic mine water discharge is complex and costly. Existing treatment methods mainly include adsorption, neutralization, and biological methods. However, these technologies are limited by their single application and cannot completely treat acidic mine water, resulting in a situation where the treatment only addresses the symptoms. Furthermore, since most existing technologies focus on remediation, only considering the exceedance of standards at the discharge point, they do not pay much attention to the generation of acidic mine water at its source. This means that even if the treated acidic water meets the standards, it will continue to acidify, negating the purpose of the remediation. Summary of the Invention

[0003] To solve the above-mentioned technical problems, this invention provides an integrated on-site prevention and control system and method for acidic mine water, thereby preventing the occurrence of acidification and achieving the goal of truly integrated treatment of acidic mine water. At the same time, it realizes the recovery of refined sulfur ore, achieving a perfect combination of economic, social and environmental benefits.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: an integrated on-site prevention and control system for acidic mine water, comprising a pretreatment section, a treatment section, a solid-liquid separation section, and an acid backflow prevention section. The outlet of the pretreatment section is connected to the inlet of the treatment section, the first outlet of the treatment section is connected to the inlet of the solid-liquid separation section, and the second outlet of the treatment section and the liquid outlet of the solid-liquid separation section are both connected to the inlet of the acid backflow prevention section.

[0005] The pretreatment section is used to remove solid impurities from acidic mine water; the treatment system uses the principle of microbial electrochemical coupling to treat acidic mine water and produce methane; the solid-liquid separation section separates the refined sulfur ore produced after the acidic mine water treatment; the anti-acid-back section further treats the treated acidic mine water to ensure that the discharged wastewater does not return to acid.

[0006] The pretreatment section includes a pretreatment tank, inside which, from front to back, are arranged a grid device, a flocculant uniform addition device, a sponge adsorption device, and a pH-adjusting calcium hydroxide addition device.

[0007] The treatment section employs a microbial electrolysis device, which includes a DC regulated power supply, an electrolytic cell, a peristaltic pump, an anode iron plate, a cathode iron plate, an anode carbon felt, a cathode graphite rod, a proton exchange membrane, a voltage and current regulator, and a data logger. An electrolysis inlet is located on the upper left side of the electrolytic cell. The peristaltic pump draws wastewater treated in the pretreatment section and injects it into the electrolytic cell through the electrolysis inlet. An electrolysis outlet is located on the lower right side of the electrolytic cell, and a gas collection port is located at the top right side of the electrolytic cell. The proton exchange membrane is positioned in the middle of the electrolytic cell, dividing it into an anode chamber on the left and a cathode chamber on the right. The anode iron plate and cathode iron plate are respectively located within the anode and cathode chambers. The anode carbon felt is placed on the anode iron plate, and the cathode graphite rod is connected to the cathode iron plate. The anode iron plate is connected to the positive terminal of the DC regulated power supply via a first titanium wire. The voltage and current regulator and data logger are mounted on the first titanium wire. The cathode iron plate is connected to the negative terminal of the DC regulated power supply via a second titanium wire. A stirrer is located within both the anode and cathode chambers.

[0008] The solid-liquid separation section includes a centrifugal solid-liquid separator and a sedimentation tank. The separation inlet of the centrifugal solid-liquid separator is connected to the electrolysis outlet at the lower right side of the electrolysis cell. The bottom outlet of the centrifugal solid-liquid separator is connected to the inlet of the sedimentation tank. The top outlet of the centrifugal solid-liquid separator and the outlet of the sedimentation tank are both connected to the inlet of the anti-acid backflow section.

[0009] The anti-acid backflow section includes an aluminum clay mineral dosing device and a composite anti-acid bacteria agent adding device. The aluminum clay mineral dosing device adds aluminum clay minerals to the wastewater after electrolysis and solid-liquid separation, while the composite anti-acid bacteria agent adding device adds composite anti-acid bacteria agent to the wastewater after electrolysis and solid-liquid separation.

[0010] A method for the prevention and control of acidic mine water in an integrated on-site system includes the following steps:

[0011] (1) The pretreatment section removes solid impurities from the acidic mine water;

[0012] (2) The treatment section involves electrolytic treatment of the pretreated acidic mine water;

[0013] (3) If the wastewater after electrolysis treatment contains SO4 2- If the concentration is high, the passage between the treatment section and the acid backflow prevention section will be closed, and the wastewater will undergo solid-liquid separation through the solid-liquid separation section; if the wastewater after electrolytic treatment contains SO4 2- When the concentration is less than or equal to 100 mg / L, the passage between the treatment section and the solid-liquid separation section is closed, and the wastewater is further treated through the anti-acid backflow section to keep the pH of the treated wastewater stable and prevent acid backflow.

[0014] (4) The solid-liquid separation section separates and precipitates the suspended solids in the wastewater to obtain refined sulfur ore. The separated wastewater is then discharged into the anti-acid-return section for further treatment to keep the pH of the treated wastewater stable and prevent acid reversion.

[0015] Step (1) is as follows: Acidic mine water is introduced into the pretreatment tank and first passes through a screen device to isolate large debris. The flocculant uniform addition device adds flocculant to the pretreatment tank, and the flocculant adsorbs large particles of debris to make them precipitate. The sponge adsorption device adsorbs small particles of debris to make them precipitate. Finally, the pH adjustment calcium hydroxide addition device adds calcium hydroxide to the acidic mine water to adjust the pH value of the acidic mine water to be suitable for electrolytic treatment.

[0016] The treatment part of step (2) uses a microbial electrolysis device, with laboratory-purified SRB and enriched microbial community as a biocatalyst. The acidic mine water is treated by a microbial electrolysis cell-microbial fuel cell coupling system. Through SRB domestication of acidic wastewater, anode carbon felt and cathode graphite rod, a microbial electrochemical system is constructed to directly treat acidic wastewater and remove sulfate ions from acidic mine water.

[0017] Before use, the anode and cathode iron plates of the microbial electrolysis device are soaked in 10% dilute hydrochloric acid for 2 hours to remove surface oxides.

[0018] The specific process of step (2) is as follows: the pretreated acidic mine water enters the anode chamber of the electrolytic cell under the suction of the peristaltic pump. The agitator stirs the acidic mine water at a constant speed. When the acidic mine wastewater submerges the anode iron plate and cathode iron plate, the peristaltic pump and the electrolytic inlet are turned off. Then, a sodium bicarbonate buffer solution containing 0.5 g / L potassium acetate is injected into the anode chamber. Pure bacterial solution and culture medium accounting for 10% of the total volume of the cathode chamber are injected into the cathode chamber. The cathode chamber and anode chamber are separated by a proton exchange membrane. The [COD] / [SO4] ratio in the electrolytic cell is... 2- The ratio of [] is preferably 2.2. Turn on the DC regulated power supply, and apply a voltage between 0.5 and 0.7V. Start the voltage and current regulator and data logger. Introduce a 3:1 N2 / Ar gas into the headspace of the upper space of the electrolytic cell for 3 minutes to ensure an anaerobic environment in the reactor. The hydraulic retention time is between 24 and 48 hours. The reactor is placed in an environment preferably between 30 and 35°C. The graphite felt electrode in the cathode chamber is flushed every 3 to 5 days, and the sulfur element produced by reduction on the cathode iron plate is collected. A heavy metal precipitate recovery device is connected to the bottom of the electrolytic cell. The microbial electrolysis device operates intermittently, and the generated CH4 is discharged and collected through the gas collection port.

[0019] The specific process of further treatment in step (3) of the anti-acidification part is as follows: The aluminum-containing clay mineral addition device of the anti-acidification part adds clay mineral kaolin to the wastewater after electrolysis treatment. The wastewater contains a lot of iron ions. The addition of clay mineral kaolin forms a new secondary mineral film on the surface of pyrite, which prevents the continuous contact between water, oxygen and pyrite, blocks the dissolution channel, and thus inhibits the oxidation and dissolution of pyrite. This causes the formation and thickening of the film barrier layer on the surface of pyrite, forming a film fixed mineral layer composed of film and secondary minerals on the surface of pyrite, thus producing a passivation phenomenon. The addition of clay mineral kaolin accelerates the hydrolysis and precipitation rate of iron ions in the water, on the one hand reducing the Fe in the solution. 3+ The concentration inhibits the continued oxidation of intermediate products of iron and sulfur oxidation; on the other hand, the formation of thin-film secondary minerals on the surface of pyrite prevents the hydrolysis reaction of pyrite; during the oxidation of pyrite, the conversion rate of Fe is greater than that of S, which promotes the further increase of thin films mainly composed of polysulfides (FeSn) or iron-deficient sulfides (Fe1-xS), forming a film-fixed mineral layer composed of thin film and secondary mineral layer, which inhibits the oxidation of pyrite; at the same time, a compound acid-resistant bacteria agent is added to the wastewater.

[0020] The specific process of solid-liquid separation in steps (3) and (4) is as follows: the wastewater is first separated by a centrifugal solid-liquid separator, and then settled in a sedimentation tank. The precipitate is refined sulfur ore. The wastewater discharged through the centrifugal solid-liquid separator and sedimentation tank flows into the anti-acid backflow section.

[0021] Culture conditions (g / L) of sulfate-reducing bacteria SRB: KH2PO4 0.5, NH4Cl 1.0, Na2SO4 0.5, 65% sodium acetate 5.0, CaCl2 0.076, MgSO4·7H2O 2.0, (NH4)2Fe(SO4)2·7H2O 0.5, ascorbic acid 0.1, peptone 1.0;

[0022] Increased addition of clay mineral kaolin (Al) 3+ A dosage of ≥25 mmol / L showed a significant inhibitory effect, and the higher the dosage, the more obvious the oxidative inhibition effect. Considering the need to avoid the turbidity caused by suspended solids in the mine water, the optimal dosage of clay mineral kaolin is 35 mmol / L.

[0023] Compared with existing technologies, the present invention is scientifically sound and easy to operate. It can be used to treat acidic mine water in coal mines, ensuring that the treated wastewater meets discharge standards and does not revert to acid. The microbial electrolysis device degrades sulfate ions in the wastewater more thoroughly, saving energy, avoiding the addition of pH adjustment agents, reducing treatment costs, and preventing secondary pollution. The treated wastewater yields refined sulfur ore, thus providing both economic and environmental benefits. Attached Figure Description

[0024] Figure 1 This is an overall structural block diagram of the present invention;

[0025] Figure 2 yes Figure 1 A structural block diagram of a microbial electrolysis device. Detailed Implementation

[0026] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples.

[0027] like Figure 1 and Figure 2 As shown, the present invention provides an integrated on-site prevention and control system for acidic mine water production sites, comprising a pretreatment section 1, a treatment section 2, a solid-liquid separation section 3, and an acid backflow prevention section 4. The outlet of the pretreatment section 1 is connected to the inlet of the treatment section 2, the first outlet of the treatment section 2 is connected to the inlet of the solid-liquid separation section 3, and the second outlet of the treatment section 2 and the liquid outlet of the solid-liquid separation section 3 are both connected to the inlet of the acid backflow prevention section 4.

[0028] The pretreatment section 1 is used to remove solid impurities from acidic mine water; the treatment system uses the principle of microbial electrochemical coupling to treat acidic mine water and produce methane; the solid-liquid separation section 3 separates the refined sulfur ore produced after the acidic mine water treatment; the anti-acid-return section 4 further treats the treated acidic mine water to ensure that the discharged wastewater does not return to acid.

[0029] The pretreatment section 1 includes a pretreatment tank, inside which, from front to back, are arranged a grid device 5, a flocculant uniform addition device 6, a sponge adsorption device 7, and a pH-adjusting calcium hydroxide addition device 8.

[0030] Treatment section 2 employs a microbial electrolysis device 9, which includes a DC regulated power supply 10, an electrolytic cell 11, a peristaltic pump 12, an anode iron plate 13, a cathode iron plate 14, an anode carbon felt 15, a cathode graphite rod 16, a proton exchange membrane 17, a voltage and current regulator 18, and a data logger 19. An electrolysis inlet 20 is located on the upper left side of the electrolytic cell 11. The peristaltic pump 12 draws wastewater from the pretreatment section 1 and injects it into the electrolytic cell 11 through the electrolysis inlet 20. An electrolysis outlet 21 is located on the lower right side of the electrolytic cell 11, and a gas collection port 22 is located on the top right side of the electrolytic cell 11. The electrolytic cell 11 is divided into an anode chamber on the left and a cathode chamber on the right by a sub-exchange membrane 17 located in the middle of the electrolytic cell 11. An anode iron plate 13 and a cathode iron plate 14 are respectively located in the anode chamber and the cathode chamber. An anode carbon felt 15 is located on the anode iron plate 13. A cathode graphite rod 16 is connected to the cathode iron plate 14. The anode iron plate 13 is connected to the positive terminal of the DC regulated power supply 10 through a first titanium wire 23. A voltage and current regulator 18 and a data logger 19 are located on the first titanium wire 23. The cathode iron plate 14 is connected to the negative terminal of the DC regulated power supply 10 through a second titanium wire 24. A stirrer is provided in both the anode chamber and the cathode chamber.

[0031] The solid-liquid separation section 3 includes a centrifugal solid-liquid separator 25 and a sedimentation tank 26. The separation inlet of the centrifugal solid-liquid separator 25 is connected to the electrolysis outlet 21 on the lower right side of the electrolysis cell 11. The bottom outlet of the centrifugal solid-liquid separator 25 is connected to the inlet of the sedimentation tank 26. The top outlet of the centrifugal solid-liquid separator 25 and the outlet of the sedimentation tank 26 are both connected to the inlet of the anti-acid backflow section 4.

[0032] The anti-acidification section 4 includes an aluminum clay mineral dosing device 27 and a composite anti-acid bacteria agent adding device 28. The aluminum clay mineral dosing device 27 adds aluminum clay minerals to the wastewater after electrolysis and solid-liquid separation, and the composite anti-acid bacteria agent adding device 28 adds composite anti-acid bacteria agent to the wastewater after electrolysis and solid-liquid separation.

[0033] A method for the prevention and control of acidic mine water in an integrated on-site system includes the following steps:

[0034] (1) Pretreatment section 1 removes solid impurities from acidic mine water;

[0035] (2) Part 2 of the treatment process involves electrolytic treatment of the pretreated acidic mine water;

[0036] (3) If the wastewater after electrolysis treatment contains SO4 2- If the concentration is high, the passage between treatment section 2 and anti-acid backflow section 4 is closed, and the wastewater undergoes solid-liquid separation through solid-liquid separation section 3; if the wastewater after electrolytic treatment contains SO4 2- Low concentration (SO4) 2-With a concentration of less than or equal to 100 mg / L, the electrolytic cell 11 can continuously receive water and open and close valves according to the sulfate ion content in the solution to allow wastewater and treated water to smoothly enter and exit the electrolytic cell 11. The passage between the treatment section 2 and the solid-liquid separation section 3 is closed, and the wastewater is further treated through the anti-acid backflow section 4 to keep the pH of the treated wastewater stable and prevent acid backflow.

[0037] (4) Solid-liquid separation section 3 separates and precipitates the suspended solids in the wastewater to obtain refined sulfur ore. The separated wastewater is then discharged into the anti-acid backflow section 4 for further treatment to keep the pH of the treated wastewater stable and prevent acid backflow.

[0038] Step (1) is as follows: Acidic mine water is introduced into the pretreatment tank and first passes through the screen device 5. The screen device 5 isolates large pieces of debris. The flocculant uniform addition device 6 adds flocculant to the pretreatment tank. The flocculant adsorbs large particles of debris and causes them to precipitate. The sponge adsorption device 7 adsorbs small particles of debris and causes them to precipitate. Finally, the pH adjustment calcium hydroxide addition device 8 adds calcium hydroxide to the acidic mine water to adjust the pH value of the acidic mine water to be suitable for electrolytic treatment.

[0039] In step (2), the treatment part 2 uses a microbial electrolysis device 9, with laboratory-purified SRB and enriched microbial communities as biocatalysts. The acidic mine water is treated using a microbial electrolysis cell 11-microbial fuel cell coupling system. Through acidic wastewater SRB domestication, anode carbon felt 15 and cathode graphite rod 16, a microbial electrochemical system is constructed to directly treat acidic wastewater and remove sulfate ions from acidic mine water.

[0040] Before use, the anode iron plate 13 and cathode iron plate 14 of the microbial electrolysis device 9 are soaked in 10% dilute hydrochloric acid for 2 hours to remove surface oxides.

[0041] The specific process of step (2) is as follows: the pretreated acidic mine water enters the anode chamber of the electrolytic cell 11 under the suction of the peristaltic pump 12. The agitator stirs the acidic mine water at a constant speed. When the acidic mine wastewater submerges the anode iron plate 13 and the cathode iron plate 14, the peristaltic pump 12 and the electrolytic inlet 20 are turned off. Then, a sodium bicarbonate buffer solution containing 0.5 g / L potassium acetate is injected into the anode chamber. Pure bacterial solution and culture medium accounting for 10% of the total volume of the cathode chamber are injected into the cathode chamber. The cathode chamber and the anode chamber are separated by a proton exchange membrane 17. The [COD] / [SO4] ratio in the electrolytic cell 11 is... 2-The ratio of [] is preferably 2.2. Turn on the DC regulated power supply 10, and apply a voltage between 0.5 and 0.7V. Start the voltage and current regulator 18 and the data logger 19. Introduce N2 / Ar gas at a ratio of 3:1 into the headspace of the upper space of the electrolytic cell 11 for 3 minutes to ensure an anaerobic environment in the reactor. The hydraulic retention time is between 24 and 48 hours. The reactor is placed in an environment preferably between 30 and 35°C. The graphite felt electrode in the cathode chamber is flushed every 3 to 5 days (or automatically flushed according to the biomass on the anode and cathode). The sulfur element produced by the reduction on the cathode iron plate 14 is collected. The bottom of the electrolytic cell 11 is connected to a heavy metal precipitate recovery device. The microbial electrolysis device 9 operates intermittently. The generated CH4 is discharged and collected through the gas collection port 22.

[0042] The specific process of further treatment in step (3) of the anti-acid-return section 4 is as follows: The aluminum-containing clay mineral addition device 27 of the anti-acid-return section 4 adds clay mineral kaolin to the wastewater after electrolytic treatment. The wastewater contains a lot of iron ions. The addition of clay mineral kaolin forms a new secondary mineral film on the surface of pyrite, which prevents water and oxygen from continuously contacting pyrite, blocks the dissolution channel, and thus inhibits the oxidation and dissolution of pyrite. This causes the formation and thickening of the film barrier layer on the surface of pyrite, forming a film-fixed mineral layer composed of film and secondary minerals on the surface of pyrite, thereby producing a passivation phenomenon. The addition of clay mineral kaolin accelerates the hydrolysis and precipitation rate of iron ions in the water, on the one hand reducing the Fe in the solution. 3+ The concentration inhibits the continued oxidation of intermediate products of iron and sulfur oxidation; on the other hand, the formation of thin-film secondary minerals on the surface of pyrite prevents the hydrolysis reaction of pyrite; during the oxidation of pyrite, the conversion rate of Fe is greater than that of S, which promotes the further increase of thin films mainly composed of polysulfides (FeSn) or iron-deficient sulfides (Fe1-xS), forming a film-fixed mineral layer composed of thin film and secondary mineral layer, which inhibits the oxidation of pyrite; at the same time, a compound acid-resistant bacteria agent is added to the wastewater.

[0043] The specific process of solid-liquid separation section 3 in steps (3) and (4) is as follows: the wastewater is first separated by centrifugal solid-liquid separator 25, and then precipitated by sedimentation tank 26. The precipitate is refined sulfur ore. The wastewater discharged through centrifugal solid-liquid separator 25 and sedimentation tank 26 flows into the anti-acid section 4.

[0044] Culture conditions (g / L) of sulfate-reducing bacteria SRB: KH2PO4 0.5, NH4Cl 1.0, Na2SO4 0.5, 65% sodium acetate 5.0, CaCl2 0.076, MgSO4·7H2O 2.0, (NH4)2Fe(SO4)2·7H2O 0.5, ascorbic acid 0.1, peptone 1.0;

[0045] Increased addition of clay mineral kaolin (Al) 3+ A dosage of ≥25 mmol / L showed a significant inhibitory effect, and the higher the dosage, the more obvious the oxidative inhibition effect. Considering the need to avoid the turbidity caused by suspended solids in the mine water, the optimal dosage of clay mineral kaolin is 35 mmol / L.

[0046] The acid-resistant bacteria agent of this invention comprises the following three raw materials in the following weight ratio: 35% *Desulfobacterium*, 27% *Desulfovibrio*, and 38% *Desulfocobacillus*. The agent maintains a concentration of 55%, an OD600 of 0.2433, a pH of 7, and an Eh of -280mv.

[0047] The above embodiments illustrate the basic principles and features of the present invention, but are merely preferred embodiments and are not limited to these embodiments. Those skilled in the art, inspired by this patent, can make many modifications and improvements without departing from the spirit and scope of the claims, all of which fall within the scope of protection of the present invention. Therefore, the scope of this patent and its protection should be determined by the appended claims.

Claims

1. An integrated on-site prevention and control system for acidic mine water generation sites, characterized in that: It includes a pretreatment section, a treatment section, a solid-liquid separation section, and an anti-acid backflow section. The outlet of the pretreatment section is connected to the inlet of the treatment section, the first outlet of the treatment section is connected to the inlet of the solid-liquid separation section, and the second outlet of the treatment section and the liquid outlet of the solid-liquid separation section are both connected to the inlet of the anti-acid backflow section. The pretreatment section is used to remove solid impurities from acidic mine water; the treatment system uses the principle of microbial electrochemical coupling to treat acidic mine water and produce methane. The solid-liquid separation section separates the refined sulfur ore produced after the treatment of acidic mine water; the acid backflow prevention section further treats the treated acidic mine water to ensure that the discharged wastewater does not return to acid. The treatment section employs a microbial electrolysis device, which includes a DC regulated power supply, an electrolytic cell, a peristaltic pump, an anode iron plate, a cathode iron plate, an anode carbon felt, a cathode graphite rod, a proton exchange membrane, a voltage and current regulator, and a data logger. An electrolysis inlet is located on the upper left side of the electrolytic cell. The peristaltic pump draws wastewater treated in the pretreatment section and injects it into the electrolytic cell through the electrolysis inlet. An electrolysis outlet is located on the lower right side of the electrolytic cell, and a gas collection port is located at the top right side of the electrolytic cell. The proton exchange membrane is positioned in the middle of the electrolytic cell, dividing it into an anode chamber on the left and a cathode chamber on the right. The anode iron plate and cathode iron plate are respectively located within the anode and cathode chambers. The anode carbon felt is placed on the anode iron plate, and the cathode graphite rod is connected to the cathode iron plate. The anode iron plate is connected to the positive terminal of the DC regulated power supply via a first titanium wire. The voltage and current regulator and data logger are mounted on the first titanium wire. The cathode iron plate is connected to the negative terminal of the DC regulated power supply via a second titanium wire. A stirrer is located within both the anode and cathode chambers. The anti-acid backflow section includes an aluminum clay mineral dosing device and a composite anti-acid bacteria agent adding device. The aluminum clay mineral dosing device adds aluminum clay minerals to the wastewater after electrolysis and solid-liquid separation, while the composite anti-acid bacteria agent adding device adds composite anti-acid bacteria agent to the wastewater after electrolysis and solid-liquid separation.

2. The integrated on-site prevention and control system for acidic mine water generation sites according to claim 1, characterized in that: The pretreatment section includes a pretreatment tank, which contains, from front to back, a grid device, a flocculant uniform addition device, a sponge adsorption device, and a pH-adjusting calcium hydroxide addition device.

3. The integrated on-site prevention and control system for acidic mine water generation sites according to claim 2, characterized in that: The solid-liquid separation section includes a centrifugal solid-liquid separator and a sedimentation tank. The separation inlet of the centrifugal solid-liquid separator is connected to the electrolysis outlet at the lower right side of the electrolysis cell. The bottom outlet of the centrifugal solid-liquid separator is connected to the inlet of the sedimentation tank. The top outlet of the centrifugal solid-liquid separator and the outlet of the sedimentation tank are both connected to the inlet of the anti-acid backflow section.

4. The prevention and control method using the integrated on-site prevention and control system for acidic mine water generation as described in claim 3, characterized in that: Includes the following steps: (1) The pretreatment section removes solid impurities from the acidic mine water; (2) The treatment section involves electrolytic treatment of the pretreated acidic mine water; (3) If the wastewater after electrolysis treatment contains SO4 2- If the concentration is high, the passage between the treatment section and the acid backflow prevention section will be closed, and the wastewater will undergo solid-liquid separation through the solid-liquid separation section; if the wastewater after electrolytic treatment contains SO4 2- When the concentration is less than or equal to 100 mg / L, the passage between the treatment section and the solid-liquid separation section is closed, and the wastewater is further treated through the anti-acidification section to keep the pH of the treated wastewater stable and prevent acid backflow. (4) The solid-liquid separation section separates and precipitates the suspended solids in the wastewater to obtain refined sulfur ore. The separated wastewater is then discharged into the anti-acid backflow section for further treatment, so that the pH of the treated wastewater remains stable and no acid backflow occurs.

5. The prevention and control method according to claim 4, characterized in that: Step (1) is as follows: Acidic mine water is introduced into the pretreatment tank and first passes through a screen device to isolate large debris. The flocculant uniform addition device adds flocculant to the pretreatment tank, and the flocculant adsorbs large particles of debris to make them precipitate. The sponge adsorption device adsorbs small particles of debris to make them precipitate. Finally, the pH adjustment calcium hydroxide addition device adds calcium hydroxide to the acidic mine water to adjust the pH value of the acidic mine water to be suitable for electrolytic treatment.

6. The prevention and control method according to claim 5, characterized in that: The treatment part of step (2) uses a microbial electrolysis device, with laboratory-purified SRB and enriched microbial community as a biocatalyst. The acidic mine water is treated by a microbial electrolysis cell-microbial fuel cell coupling system. Through SRB domestication of acidic wastewater, anode carbon felt and cathode graphite rod, a microbial electrochemical system is constructed to directly treat acidic wastewater and remove sulfate ions from acidic mine water. Before use, the anode and cathode iron plates of the microbial electrolysis device are soaked in 10% dilute hydrochloric acid for 2 hours to remove surface oxides. The specific process of step (2) is as follows: the pretreated acidic mine water enters the anode chamber of the electrolytic cell under the suction of the peristaltic pump. The agitator stirs the acidic mine water at a constant speed. When the acidic mine wastewater submerges the anode iron plate and cathode iron plate, the peristaltic pump and the electrolytic inlet are turned off. Then, a sodium bicarbonate buffer solution containing 0.5 g / L potassium acetate is injected into the anode chamber. Pure bacterial solution and culture medium accounting for 10% of the total volume of the cathode chamber are injected into the cathode chamber. The cathode chamber and the anode chamber are separated by a proton exchange membrane. The [COD] / [SO4] ratio in the electrolytic cell is... 2- The ratio of [] is 2.

2. Turn on the DC regulated power supply, and apply a voltage between 0.5 and 0.7V. Start the voltage and current regulator and data logger. Introduce N2 / Ar gas at a ratio of 3:1 into the headspace of the upper space of the electrolytic cell for 3 minutes to ensure an oxygen-free environment in the reactor. The hydraulic retention time is between 24 and 48 hours. The reactor is placed in an environment with a temperature of 30 to 35°C. The graphite felt electrode in the cathode chamber is flushed every 3 to 5 days, and the sulfur element produced by reduction on the cathode iron plate is collected. A heavy metal precipitate recovery device is connected to the bottom of the electrolytic cell. The microbial electrolysis device is operated intermittently, and the methane produced is discharged and collected through the gas collection port.

7. The prevention and control method according to claim 6, characterized in that: The specific process of further treatment in step (3) of the anti-acidification part is as follows: The aluminum-containing clay mineral addition device of the anti-acidification part adds clay mineral kaolin to the wastewater after electrolysis treatment. The wastewater contains a lot of iron ions. The addition of clay mineral kaolin forms a new secondary mineral film on the surface of pyrite, which prevents the continuous contact between water, oxygen and pyrite, blocks the dissolution channel, and thus inhibits the oxidation and dissolution of pyrite. This causes the film barrier layer on the surface of pyrite to form and thicken, forming a film fixed mineral layer on the surface of pyrite composed of film and secondary minerals, thus producing a passivation phenomenon. The addition of clay mineral kaolin accelerates the hydrolysis and precipitation rate of iron ions in the water, on the one hand reducing the Fe in the solution. 3+ The concentration inhibits the continued oxidation of intermediate products from iron and sulfur oxidation; on the other hand, the formation of thin-film secondary minerals on the pyrite surface prevents the hydrolysis reaction of pyrite; during the oxidation of pyrite, the Fe conversion rate is greater than that of S, which promotes the further increase of the film mainly composed of polysulfide compounds or iron-deficient sulfides, forming a film-fixed mineral layer composed of the film and the secondary mineral layer, thus inhibiting the oxidation of pyrite; at the same time, a compound acid-resistant bacteria agent is added to the wastewater; The specific process of solid-liquid separation in steps (3) and (4) is as follows: the wastewater is first separated by a centrifugal solid-liquid separator, and then settled in a sedimentation tank. The precipitate is refined sulfur ore. The wastewater discharged through the centrifugal solid-liquid separator and sedimentation tank flows into the anti-acid backflow section.

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