Treatment device and method for treating high-concentration sulfate wastewater

Abstract

The invention relates to the technical field of wastewater treatment, and provides a treatment device and method for treating high-concentration sulfate wastewater, and the device comprises a pretreatment unit, a bioreactor, a chemical precipitation unit and a solid-liquid separation unit; the pretreatment unit comprises a pH adjusting tank and a constant temperature device and is used for adjusting the pH value and the temperature of wastewater; the bioreactor is filled with a hydrogen sulfide adsorption filler layer and a sulfate reducing bacteria immobilization carrier; a stirring device and a calcium salt adding device are arranged in the chemical precipitation unit, and the chemical precipitation unit is connected with the bioreactor through an overflow pipe; the solid-liquid separation unit comprises an inclined plate sedimentation tank and a precision filter and is used for carrying out solid-liquid separation on the wastewater. According to the invention, two-stage cooperative processing is adopted, so that both efficiency and economy are improved; sludge reduction and resource recovery are carried out; modularized and intelligent design is carried out, operation is stable, and maintenance is easy.

Description

Technical Field

[0001] The present invention relates to the technical field of wastewater treatment, and in particular to a treatment device and method for treating high-concentration sulfate wastewater. Background Art

[0002] In recent years, sulfate wastewater pollution has become increasingly serious. Vast quantities of industrial wastewater containing high sulfate concentrations have emerged from numerous production sectors, including chemical, pharmaceutical, leather, papermaking, fermentation, food processing, and mining. Sulfate wastewater is characterized by its wide contamination area, long incubation period, and difficulty in treatment. Among the well-known water pollution issues in the Huaihe River Basin, sulfate-rich monosodium glutamate wastewater is the second-largest source of pollution. Furthermore, groundwater in many Chinese cities has been contaminated to varying degrees by sulfate. Therefore, the search for effective sulfate wastewater treatment processes has become a widespread concern within the environmental engineering community.

[0003] Traditional treatment methods such as chemical precipitation (adding calcium salts to generate CaSO4) have problems such as high reagent consumption and large amount of sludge; biological methods (sulfate-reducing bacteria) have low efficiency in treating high-concentration wastewater and are easily inhibited by toxicity.

[0004] Existing single physical, chemical, or biological treatment methods are difficult to achieve both economic efficiency and treatment efficiency. Therefore, there is an urgent need to develop an integrated technology that is efficient, low-energy, and can stably treat high-concentration sulfate wastewater. Summary of the Invention

[0005] The present invention provides a treatment device and method for treating high-concentration sulfate wastewater, aiming to solve the above-mentioned problem.

[0006] The present invention is achieved by providing a treatment device and method for treating high-concentration sulfate wastewater, wherein the treatment device for treating high-concentration sulfate wastewater comprises: a pretreatment unit, a bioreactor, a chemical precipitation unit, and a solid-liquid separation unit;

[0007] The pretreatment unit includes a pH adjustment tank and a constant temperature device to adjust the pH value and temperature of the wastewater;

[0008] The bioreactor is filled with a hydrogen sulfide adsorption filler layer and a sulfate-reducing bacteria immobilization carrier;

[0009] The chemical precipitation unit has a built-in stirring device and a calcium salt dosing device, and is connected to the bioreactor through an overflow pipe;

[0010] The solid-liquid separation unit includes an inclined plate sedimentation tank and a precision filter to separate the solid and liquid of the wastewater.

[0011] Preferably, the pH adjustment tank is cylindrical in structure, with a detachable sealing cover on the top, and the body of the adjustment tank is made of corrosion-resistant fiberglass or polypropylene; an agitator is provided at the bottom of the pH adjustment tank, and the blades of the agitator are made of stainless steel; a pH probe is installed on the side wall of the pH adjustment tank, and the pH probe is used to monitor the pH value of the wastewater in the pH adjustment tank in real time. The pH probe is connected to a PLC controller, and the PLC controller receives the pH value of the liquid in the pH adjustment tank transmitted by the pH probe. When adjusting the pH value, the agitator continues to stir to ensure that the pH is uniform. ; A feeding port is provided on the side wall of the pH regulating tank, and the feeding port is connected to the acid storage tank and the alkali storage tank through a pipe. The acid storage tank and the alkali storage tank are both equipped with a metering pump. The liquid in the acid storage tank and the alkali storage tank is input into the pH regulating tank through the metering pump. The metering pump is connected to the PLC controller, and the PLC controller controls the amount of acid or alkali delivered by the metering pump in the acid storage tank and the alkali storage tank to adjust the pH value of the liquid in the tank; an overflow port is provided on the upper part of the regulating tank body, and the overflow port is connected to the constant temperature device through an overflow pipe, and an overflow pump is installed on the overflow pipe.

[0012] Preferably, the main body of the constant temperature device is a double-layer tank body, which is made of stainless steel. Circulating water is passed into the outer layer of the tank. A temperature sensor is provided in the tank body. A circulating water heater and a cooling coil are provided outside the tank body. The water outlet of the circulating water heater is connected to the tank body, and the water inlet is connected to the outer layer of the tank through a pipe. The circulating water in the outer layer of the tank enters the circulating water heater through the pipe, and re-enters the tank body after being heated by the circulating water heater to maintain the temperature of the circulating water. The cooling coil is connected to cold water. The circulating water heater and the cooling coil are both linked to the temperature sensor. According to the temperature sensor, a porous distribution plate is provided in the tank body to make the wastewater flow evenly through the heat exchange area to avoid local temperature fluctuations.

[0013] Preferably, the bioreactor is a vertical cylindrical reactor, the hydrogen sulfide adsorption filler layer is placed on the upper part of the bioreactor, the hydrogen sulfide adsorption filler layer is filled with activated carbon fiber loaded with Fe2O3, and a stainless steel grid is provided at the bottom of the hydrogen sulfide adsorption filler layer, which supports the hydrogen sulfide adsorption filler layer; the sulfate-reducing bacteria immobilization carrier area is located in the middle of the bioreactor, the sulfate-reducing bacteria immobilization carrier area is filled with sulfate-reducing bacteria agent embedded in polyvinyl alcohol-sodium alginate, and the sulfate-reducing bacteria immobilization carrier area is provided with multiple vertical guide plates, which are used to extend the hydraulic retention time; an annular microporous aeration tube is arranged at the bottom of the bioreactor, and the annular microporous aeration tube is connected to an external nitrogen source to maintain an anaerobic environment in the tube. Under anaerobic conditions, sulfate-reducing bacteria will Restore to H2S gas generated by the biological reaction rises to the hydrogen sulfide adsorption packing layer, where the activated carbon fibers loaded with Fe2O3 fix the H2S through chemical adsorption. An overflow port is located at the top of the bioreactor's sidewall, and a sludge discharge valve is located in the conical structure at the bottom, allowing for regular sludge removal and removal of aging biofilm.

[0014] Preferably, the stirring device includes a reaction tank and a stirrer, the stirrer is installed on the top of the reaction tank, and a baffle is provided in the reaction tank, which enhances turbulence, prevents short flow, and strengthens the mixing effect; the calcium salt adding device includes a storage bin, a screw conveyor and an online sulfate detector, the storage bin is connected to the reaction tank through the screw conveyor, the online sulfate detector is arranged on the inner wall of the screw conveyor near the output port, and the addition amount is feedback controlled by the online sulfate detector.

[0015] Preferably, the blades of the mixer cover 80% of the cross section of the tank body, and the surface of the blades of the mixer is coated with a polytetrafluoroethylene anti-scaling coating.

[0016] Preferably, the inclined plate sedimentation tank includes a sedimentation tank body, an inlet is provided on one side of the sedimentation tank body, and an outlet is provided on the other side. A group of inclined plate components are evenly spaced inside the sedimentation tank body to increase the sedimentation area. A conical sludge hopper is provided at the bottom of the inclined plate sedimentation tank, and a pneumatic sludge discharge valve is provided at the outlet of the conical sludge hopper. The inclined plate sedimentation tank and the bioreactor are connected through a pipeline provided with a sludge pump to transport the sludge in the inclined plate sedimentation tank to the bioreactor.

[0017] Preferably, the precision filter includes a tank body, which adopts a multi-stage filtration structure of a precision filter. The upper part of the tank body is filled with a quartz sand filter layer to intercept particles with smaller particle sizes. A hollow fiber ultrafiltration membrane assembly is installed at the lower part of the tank body to intercept colloids and macromolecular substances. The water outlet of the precision filter is provided with a water outlet detector.

[0018] A method for treating high-concentration sulfate wastewater, comprising the following steps:

[0019] The wastewater is passed into the pretreatment unit, which controls the pH of the pH adjustment tank and the operation of the constant temperature device to adjust the wastewater to a suitable pH and temperature;

[0020] The regulated wastewater enters the bioreactor, and nitrogen is introduced into the annular microporous aeration pipe at the bottom of the bioreactor for anaerobic treatment. Sulfate-reducing bacteria Restore to (Reaction formula: The activated carbon fiber loaded with Fe2O3 adsorbs the generated H2S;

[0021] The effluent from the bioreactor enters the chemical precipitation unit, and the online sulfate detector analyzes the remaining concentration, controlling the screw conveyor to add Ca(OH)2 powder to the reaction tank;

[0022] The effluent from chemical precipitation enters the inclined plate sedimentation tank, and the wastewater slowly rises along the inclined inclined plate. The sludge settles to the bottom sludge hopper under the action of gravity, and the supernatant is transported to the precision filter through the top overflow port. After double filtration, it is tested from the outlet of the precision filter through the online detector, and the data is uploaded to the central control system in real time. If the clean water meets the standard, it will be discharged. If the test exceeds the standard, the PLC will automatically close the outlet valve and return the water to the pH adjustment tank for pH re-treatment; after solid-liquid separation, part of the sludge will be returned to the bioreactor.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. Two-stage synergistic treatment, double improvement of efficiency and economy: divided into biological reduction stage and chemical precipitation stage, synergistic effect: the biological stage produces With chemical addition Direct reaction generates CaS precipitation, avoiding secondary pollution of intermediate products (such as H2S);

[0025] 2. Sludge reduction and resource recovery: Using SRB immobilization technology, polyvinyl alcohol-sodium alginate embedding carriers prolong the life of the bacterial community and reduce the amount of biological sludge; using a sludge return design, part of the sludge from the inclined plate sedimentation tank is returned to the bioreactor to replenish the active bacterial community and reduce the frequency of bacterial agent addition;

[0026] 3. Modular and intelligent design, stable operation and easy maintenance: Each treatment unit (bioreactor, sedimentation tank, etc.) is connected by flanges, supporting parallel expansion; the PLC system controls parameters such as pH, temperature, aeration volume, and dosage in real time; and automatic alarms for abnormal operating conditions (such as pH exceeding the limit and filter blockage) reduce the need for manual inspections. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0028] Figure 1 1 is an overall connection diagram of an embodiment of the present invention;

[0029] Figure 2 1 is a schematic cross-sectional view of a pH adjustment tank according to an embodiment of the present invention;

[0030] Figure 3 1 is a schematic cross-sectional view of a thermostat according to an embodiment of the present invention;

[0031] Figure 4 is a schematic cross-sectional view of a bioreactor according to an embodiment of the present invention;

[0032] Figure 5 is a cross-sectional schematic diagram of a chemical precipitation unit according to an embodiment of the present invention;

[0033] Figure 6 1 is a schematic cross-sectional view of an inclined plate sedimentation tank according to an embodiment of the present invention;

[0034] Figure 7 It is a cross-sectional schematic diagram of a precision filter according to an embodiment of the present invention.

[0035] The markings in the figure are: 1. pH adjustment tank; 101. Adjustment tank body; 102. Agitator; 103. Acid storage tank; 104. Alkali storage tank; 105. pH probe; 106. Overflow port; 2. Constant temperature device; 201. Constant temperature tank body; 202. Temperature sensor; 203. Cooling coil; 204. Circulating water heater; 205. Porous distribution plate; 3. Bioreactor; 301. Hydrogen sulfide adsorption packing layer; 302. Stainless steel grid; 303. Sulfate-reducing bacteria immobilization Carrier; 304, vertical guide plate; 4, chemical precipitation unit; 401, reaction tank; 402, mixer; 403, baffle; 404, storage silo; 405, screw conveyor; 406, online sulfate detector; 5, inclined plate sedimentation tank; 501, sedimentation tank body; 502, inlet; 503, outlet; 504, inclined plate assembly; 505, conical sludge hopper; 6, precision filter; 601, filter tank body; 602, quartz sand filter layer; 603, hollow fiber ultrafiltration membrane assembly. DETAILED DESCRIPTION

[0036] In order to more fully understand the technical content of the present invention, the technical solution of the present invention is further introduced and illustrated in conjunction with specific embodiments below, but is not limited thereto. The technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0037] refer to Figures 1 to 7 , the treatment device for treating high-concentration sulfate wastewater includes: a pretreatment unit, a bioreactor 3, a chemical precipitation unit 4 and a solid-liquid separation unit;

[0038] The pretreatment unit includes a pH adjustment tank 1 and a constant temperature device 2, which are used to adjust the pH value and temperature of the wastewater;

[0039] The pH regulating tank 1 is a cylindrical structure with a removable sealing cover on the top. The regulating tank body 101 is made of corrosion-resistant fiberglass or polypropylene (PP). A stirrer 102 is provided at the bottom of the pH regulating tank 1, and the blades of the stirrer 102 are made of stainless steel; a pH probe 105 is installed on the side wall of the pH regulating tank 1, and the pH probe 105 is used to monitor the pH value of the wastewater in the pH regulating tank 1 in real time. The pH probe 105 is connected to a PLC controller, and the PLC controller receives the pH value of the liquid in the pH regulating tank 1 transmitted by the pH probe 105. When adjusting the pH value, the stirrer 102 stirs continuously to ensure that the pH is uniform; a dosing port is provided on the side wall of the pH regulating tank 1, and the dosing port is connected to the acid storage tank 103 and The alkali storage tank 104, the acid storage tank 103 and the alkali storage tank 104 are all equipped with metering pumps. The liquid in the acid storage tank 103 and the alkali storage tank 104 is input into the pH regulating tank 1 through the metering pump. The metering pump is connected to the PLC controller. The PLC controller controls the amount of acid or alkali delivered by the metering pumps in the acid storage tank 103 and the alkali storage tank 104 to adjust the pH value of the liquid in the regulating tank 1; an overflow port 106 is provided on the upper part of the regulating tank body 101 of the pH regulating tank 1, and the overflow port 106 is connected to the constant temperature device 2 through an overflow pipe, and an overflow pump is installed on the overflow pipe.

[0040] The main body of the constant temperature device 2 is a double-layer constant temperature tank body 201, which is made of stainless steel. Circulating water is passed into the outer layer of the constant temperature tank body 201. A temperature sensor 202 is provided in the constant temperature tank body 201. A circulating water heater 204 and a cooling coil 203 are provided outside the constant temperature tank body 201. The water outlet of the circulating water heater 204 is connected to the constant temperature tank body 201, and the water inlet is connected to the outer layer of the constant temperature tank body 201 through a pipe. The circulating water in the outer layer of the constant temperature tank body 201 enters the circulating water heater 204 through the pipe, and is heated by the circulating water heater 204 before re-entering the constant temperature tank body 201 to maintain the temperature of the circulating water. The cooling coil 203 is connected to cold water. The circulating water heater 204 and the cooling coil 203 are both linked to the temperature sensor 202. According to the temperature sensor 202, a porous distribution plate 205 is provided in the constant temperature tank body 201 to make the wastewater flow evenly through the heat exchange area to avoid local temperature fluctuations.

[0041] The bioreactor 3 is filled with a hydrogen sulfide adsorption filler layer 301 and a sulfate-reducing bacteria (SRB) immobilization carrier;

[0042] The bioreactor 3 is a vertical cylindrical reactor. The hydrogen sulfide adsorption filler layer 301 is placed on the upper part of the bioreactor 3. The hydrogen sulfide adsorption filler layer 301 is filled with activated carbon fibers loaded with Fe2O3. A stainless steel grid 302 is provided at the bottom of the hydrogen sulfide adsorption filler layer 301. The stainless steel grid 302 supports the hydrogen sulfide adsorption filler layer 301. The SRB immobilized carrier area is located in the middle of the bioreactor 3. The SRB immobilized carrier area is filled with SRB bacteria embedded in polyvinyl alcohol-sodium alginate. The SRB immobilized carrier area is provided with multiple sections of vertical guide plates 304. The vertical guide plates 304 are used to extend the hydraulic retention time. An annular microporous aeration tube is arranged at the bottom of the bioreactor 3 with a gas-water ratio of 1:15. The annular microporous aeration tube is connected to an external nitrogen source to maintain an anaerobic environment in the tube. Under anaerobic conditions, SRB will Restore to H2S gas generated by the biological reaction rises to hydrogen sulfide adsorption packing layer 301, where the activated carbon fibers loaded with Fe2O3 fix the H2S through chemical adsorption. An overflow port 106 is located at the top of the sidewall of bioreactor 3, and a sludge discharge valve is located in the conical structure at the bottom, allowing for regular sludge removal and removal of aged biofilm.

[0043] The chemical precipitation unit 4 has a built-in stirring device and a calcium salt dosing device, and is connected to the bioreactor 3 through an overflow pipe;

[0044] The stirring device includes a reaction tank 401 and a stirrer 402. The stirrer 402 is installed on the top of the reaction tank 401. The blades of the stirrer 402 cover 80% of the cross-section of the tank body. The surface of the blades of the stirrer 402 is coated with a polytetrafluoroethylene anti-scaling coating. A baffle 403 is provided in the reaction tank 401. The baffle 403 enhances turbulence, prevents short flow, and strengthens the mixing effect. The calcium salt dosing device includes a storage bin 404, a screw conveyor 405 and an online sulfate detector 406. The storage bin 404 is connected to the reaction tank 401 through the screw conveyor 405. The online sulfate detector 406 is arranged on the inner wall of the screw conveyor 405 near the output port 503. The dosage is feedback controlled by the online sulfate detector 406.

[0045] The solid-liquid separation unit includes an inclined plate sedimentation tank 5 and a precision filter 6 to separate the solid and liquid of the wastewater;

[0046] The inclined plate sedimentation tank 5 includes a sedimentation tank body 501, an inlet 502 is provided on one side of the sedimentation tank body 501, and an outlet 503 is provided on the other side. A group of inclined plate components 504 are evenly spaced inside the sedimentation tank body 501 to increase the sedimentation area. A conical sludge hopper 505 is provided at the bottom of the inclined plate sedimentation tank 5, and a pneumatic sludge discharge valve is provided at the outlet 503 of the conical sludge hopper 505; the inclined plate sedimentation tank 5 is connected to the bioreactor 3 through a pipeline provided with a sludge pump, so that the sludge in the inclined plate sedimentation tank 5 is transported to the bioreactor 3.

[0047] The precision filter 6 includes a filter tank body 601, which adopts a multi-stage filtration structure of the precision filter 6. The upper part of the filter tank body 601 is filled with a quartz sand filter layer 602 to intercept particles with smaller particle sizes. The lower part of the filter tank body 601 is installed with a hollow fiber ultrafiltration membrane component 603 to intercept colloids and macromolecular substances. The water outlet of the precision filter 6 is provided with a water outlet detector.

[0048] The method for treating high-concentration sulfate wastewater includes:

[0049] S1: The wastewater is passed into the pretreatment unit, which controls the pH adjustment tank 1 and the constant temperature device 2 to adjust the wastewater to a suitable pH and temperature;

[0050] S2: The regulated wastewater enters the bioreactor 3, and nitrogen is introduced into the annular microporous aeration pipe at the bottom of the bioreactor 3 for anaerobic treatment. Sulfate-reducing bacteria Restore to (Reaction formula: The activated carbon fiber loaded with Fe2O3 adsorbs the generated H2S;

[0051] S3: The effluent from the bioreactor 3 enters the chemical precipitation unit 4, and the online sulfate detector 406 analyzes the remaining concentration, controlling the screw conveyor 405 to add Ca(OH)2 powder to the reaction tank 401;

[0052] S4: The effluent from chemical precipitation enters the inclined plate sedimentation tank 5, and the wastewater slowly rises along the inclined inclined plate. The sludge settles to the bottom sludge hopper under the action of gravity, and the supernatant is transported to the precision filter 6 through the top overflow port 106. After double filtration, it is tested through the online detector from the outlet of the precision filter 6, and the data is uploaded to the central control system in real time. If the clean water meets the standard, it will be discharged. If the test exceeds the standard, the PLC will automatically close the outlet valve and return the water to the pH adjustment tank 1 for reprocessing; after solid-liquid separation, the sludge part will return to the bioreactor 3.

[0053] The embodiments described above are only part of the embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any ordinary technician in the field, within the technical scope disclosed by the present invention, can make equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention, which should be covered by the scope of protection of the present invention.

Claims

1. A treatment device for treating high-concentration sulfate wastewater, characterized in that: The treatment device for treating high-concentration sulfate wastewater comprises: a pretreatment unit, a bioreactor (3), a chemical precipitation unit (4) and a solid-liquid separation unit; The pretreatment unit includes a pH regulating tank (1) and a constant temperature device (2) for adjusting the pH value and temperature of the wastewater; The bioreactor (3) is filled with a hydrogen sulfide adsorption filler layer (301) and a sulfate-reducing bacteria immobilization carrier (303); The chemical precipitation unit (4) has a built-in stirring device and a calcium salt dosing device, and is connected to the bioreactor (3) through an overflow pipe; The solid-liquid separation unit comprises an inclined plate sedimentation tank (5) and a precision filter (6) for performing solid-liquid separation on wastewater.

2. The device for treating high-concentration sulfate wastewater according to claim 1, wherein: The pH regulating tank (1) is a cylindrical structure with a detachable sealing cover on the top. The regulating tank body (101) is made of corrosion-resistant glass fiber reinforced plastic or polypropylene. A stirrer (102) is provided at the bottom of the pH regulating tank (1). The blades of the stirrer (102) are made of stainless steel. A pH probe (105) is installed on the side wall of the pH regulating tank (1). The pH probe (105) is used to monitor the pH value of the wastewater in the pH regulating tank (1) in real time. The pH probe (105) is connected to a PLC controller. The PLC controller receives the pH value of the liquid in the pH regulating tank (1) transmitted by the pH probe (105). When adjusting the pH value, the stirrer (102) continuously stirs to ensure that the pH is uniform. The pH regulating tank (1) ) is provided with a feeding port on the side wall, and the feeding port is connected to an acid storage tank (103) and an alkali storage tank (104) through a pipeline. The acid storage tank (103) and the alkali storage tank (104) are both provided with metering pumps. The liquid in the acid storage tank (103) and the alkali storage tank (104) is input into the pH regulating tank (1) through the metering pumps. The metering pumps are connected to a PLC controller. The PLC controller controls the amount of acid or alkali delivered by the metering pumps in the acid storage tank (103) and the alkali storage tank (104) to adjust the pH value of the liquid in the regulating tank (1); an overflow port (106) is provided on the upper part of the regulating tank body (101), and the overflow port (106) is connected to the constant temperature device (2) through an overflow pipe. The overflow pipe is provided with an overflow pump.

3. The device for treating high-concentration sulfate wastewater according to claim 1, wherein: The main body of the thermostatic device (2) is a double-layer thermostatic tank (201), the thermostatic tank (201) is made of stainless steel, circulating water is introduced into the outer layer of the thermostatic tank (201), a temperature sensor (202) is provided inside the thermostatic tank (201), a circulating water heater (204) and a cooling coil (203) are provided outside the thermostatic tank (201), the water outlet of the circulating water heater (204) is connected to the thermostatic tank (201), and the water inlet is connected to the outer layer of the thermostatic tank (201) through a pipeline, and the thermostatic tank (201) is connected to the outer layer of the thermostatic tank (201). 1) The circulating water in the outer layer enters the circulating water heater (204) through a pipe, is heated by the circulating water heater (204), and then re-enters the constant temperature tank (201) to maintain the temperature of the circulating water. The cooling coil (203) is externally connected to cold water. The circulating water heater (204) and the cooling coil (203) are both linked to the temperature sensor (202). According to the temperature sensor (202), a porous distribution plate (205) is set in the constant temperature tank (201) to make the wastewater flow evenly through the heat exchange area to avoid local temperature fluctuations.

4. The device for treating high-concentration sulfate wastewater according to claim 1, wherein: The bioreactor (3) is a vertical cylindrical reactor. A hydrogen sulfide adsorption filler layer (301) is placed on the upper part of the bioreactor (3). The hydrogen sulfide adsorption filler layer (301) is filled with activated carbon fibers loaded with Fe2O3. A stainless steel grid (302) is provided at the bottom of the hydrogen sulfide adsorption filler layer (301). The stainless steel grid (302) supports the hydrogen sulfide adsorption filler layer (301). The sulfate-reducing bacteria immobilization carrier (303) is located in the middle of the bioreactor (3). The sulfate-reducing bacteria immobilization carrier (303) is filled with a sulfate-reducing bacteria agent embedded in polyvinyl alcohol-sodium alginate. The sulfate-reducing bacteria immobilization carrier (303) is provided with a plurality of vertical guide plates (304) for extending the hydraulic retention time. The bottom of the bioreactor (3) is provided with an annular microporous aeration tube, which is connected to an external nitrogen source to maintain an anaerobic environment in the tube. Under anaerobic conditions, sulfate-reducing bacteria convert SO42 - Restore to S2 - The H2S gas generated by the biological reaction rises to the hydrogen sulfide adsorption filler layer (301), where the activated carbon fibers loaded with Fe2O3 fix the H2S through chemical adsorption. An overflow port (106) is provided at the top of the side wall of the bioreactor (3), and a sludge discharge valve is provided in the conical structure at the bottom to discharge sludge and remove aged biofilm regularly.

5. The device for treating high-concentration sulfate wastewater according to claim 1, wherein: The stirring device comprises a reaction tank (401) and a stirrer (402), wherein the stirrer (402) is installed on the top of the reaction tank (401), and a baffle (403) is provided in the reaction tank (401), wherein the baffle (403) enhances turbulence, prevents short-flow, and strengthens the mixing effect; and the calcium salt dosing device comprises a storage bin (404), a screw conveyor (405), and an online sulfate detector (406), wherein the storage bin (404) is connected to the reaction tank (401) via the screw conveyor (405), and the online sulfate detector (406) is provided on the inner wall of the screw conveyor (405) near the output port (503), and the dosage is controlled by feedback of the online sulfate detector (406).

6. The device for treating high-concentration sulfate wastewater according to claim 5, wherein: The blades of the mixer (402) cover 80% of the cross section of the tank body, and the surface of the blades of the mixer (402) is coated with a polytetrafluoroethylene anti-scaling coating.

7. The device for treating high-concentration sulfate wastewater according to claim 1, wherein: The inclined plate sedimentation tank (5) comprises a sedimentation tank body (501), an inlet (502) is provided on one side of the sedimentation tank body (501), and an outlet (503) is provided on the other side. A group of inclined plate assemblies (504) are evenly spaced inside the sedimentation tank body (501) to increase the sedimentation area. A conical sludge hopper (505) is provided at the bottom of the inclined plate sedimentation tank (5), and a pneumatic sludge discharge valve is provided at the outlet (503) of the conical sludge hopper (505). The inclined plate sedimentation tank (5) and the bioreactor (3) are connected via a pipeline provided with a sludge pump, so that the sludge in the inclined plate sedimentation tank (5) is transported to the bioreactor (3).

8. The device for treating high-concentration sulfate wastewater according to claim 1, wherein: The precision filter (6) includes a filter tank (601), the filter tank (601) adopts a multi-stage filtering structure of the precision filter (6), the upper part of the filter tank (601) is filled with a quartz sand filter layer (602) to intercept particles with smaller particle sizes, and the lower part of the filter tank (601) is installed with a hollow fiber ultrafiltration membrane component (603) to intercept colloids and macromolecular substances. The water outlet of the precision filter (6) is provided with a water outlet detector.

9. The method for treating high-concentration sulfate wastewater according to any one of claims 1 to 8, characterized in that: Includes the following: The wastewater is passed into a pretreatment unit, which controls the pH of a pH adjustment tank (1) and the operation of a constant temperature device (2) to adjust the wastewater to a suitable pH and temperature; The regulated wastewater enters the bioreactor (3), and nitrogen is introduced into the annular microporous aeration pipe at the bottom of the bioreactor (3) for anaerobic treatment. Sulfate-reducing bacteria convert SO42 in the wastewater into - Restore to S2 - (Reaction formula: SO42 - +Organic matter → S 2- +CO2+H2O), the activated carbon fiber loaded with Fe2O3 adsorbs the generated H2S; The effluent from the bioreactor (3) enters the chemical precipitation unit (4), and the online sulfate detector (406) analyzes the residual SO42 - concentration, controlling the screw conveyor (405) to add Ca(OH)2 powder to the reaction tank (401); The effluent from chemical precipitation enters the inclined plate sedimentation tank (5), and the wastewater slowly rises along the inclined inclined plate. The sludge settles to the bottom sludge bucket under the action of gravity, and the supernatant is transported to the precision filter (6) through the top overflow port (106). After double filtration, the water outlet of the precision filter (6) is tested by an online detector, and the data is uploaded to the central control system in real time. If the clean water meets the standard, it is discharged. If the test exceeds the standard, the PLC automatically closes the outlet valve and returns the water to the pH adjustment tank (1) for pH re-treatment; After solid-liquid separation, the sludge portion is returned to the bioreactor (3).

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