Fluorine-containing wastewater advanced treatment device

Abstract

The utility model discloses fluorine -containing wastewater advanced treatment device, including control unit, inlet unit, electric flocculation reaction area, modified biochar adsorption tower and sludge separation unit, control unit is connected with inlet unit and electric flocculation reaction area signal through signal line, inlet unit is provided with raw water import, electric flocculation reaction area is connected with inlet unit through first connecting pipe intercommunication, through the cooperation of electric flocculation unit and modified biochar adsorption tower, can realize the effect that the effluent fluorine concentration steady drop reaches 1.0mg / L below, simultaneously, through the cooperation of intelligent control unit and each execution unit, can realize the automatic optimization regulation of device parameter, significantly improve system anti -impact load capacity, ensure the stable efficient operation of treatment process, through the circulation cooperation of adsorption unit and regenerative device, can realize the efficient regeneration utilization of adsorbent, through the internal circulation of regenerative liquid, can realize the concentration recovery of pollutant, significantly reduce sludge production.

Description

Technical Field

[0001] This utility model relates to the field of fluoride-containing wastewater treatment technology, specifically to a deep treatment device for fluoride-containing wastewater. Background Technology

[0002] Fluoride-containing wastewater mainly originates from industrial processes such as phosphorus chemical industry, aluminum electrolysis, photovoltaic cell manufacturing, and semiconductor etching. Excessive fluoride ions can damage human bones and nervous system, and easily corrode equipment. With increasingly stringent environmental protection requirements, emission standards in many regions require fluoride concentrations to be reduced to below 1.0 mg / L, which places extremely high demands on the deep treatment technology of fluoride-containing wastewater.

[0003] Traditional electrocoagulation devices have several problems when treating low-concentration fluoride wastewater. First, the electrode plate surface is easily coated by the generated flocs, leading to electrode passivation, reduced current efficiency, and the need for frequent cleaning or replacement of the electrodes, affecting the continuity and stability of operation. Second, excessively extending the reaction time or increasing the current to achieve deep treatment results can lead to excessive dissolution of the anode metal, producing a large amount of sludge with high water content, increasing the difficulty and cost of subsequent sludge treatment and disposal. Finally, the removal capacity of a single electrocoagulation device for low-concentration fluoride ions tends to saturate, making it difficult to consistently meet the most stringent emission standards for effluent fluoride concentration. Utility Model Content

[0004] The purpose of this invention is to provide a deep treatment device for fluoride-containing wastewater, which can solve the problems faced by traditional electrocoagulation devices in deep defluorination, such as easy passivation of electrodes, large sludge production, and insufficient and unstable removal efficiency for low concentrations of fluoride.

[0005] To solve the above-mentioned technical problems, this utility model adopts the following technical solution: a deep treatment device for fluoride-containing wastewater, including a control unit, an inlet unit, an electrocoagulation reaction zone, a modified biochar adsorption tower, and a sludge separation unit. The control unit is connected to the inlet unit and the electrocoagulation reaction zone via a signal line. The inlet unit is provided with a raw water inlet. The electrocoagulation reaction zone is connected to the inlet unit via a first connecting pipe. The modified biochar adsorption tower is connected to the electrocoagulation reaction zone via a second pipe. The sludge separation unit is connected to the modified biochar adsorption tower via a third pipe.

[0006] Preferably, the control unit includes a PLC controller, which is installed in a control cabinet and is connected to the water inlet unit, the electrocoagulation reaction zone, and the modified biochar adsorption tower via signal lines.

[0007] Preferably, the water inlet unit includes a wastewater equalization tank, a pH sensor is installed inside the wastewater equalization tank, and a dosing pump is installed inside the wastewater equalization tank. The dosing pump is connected to the wastewater equalization tank through a dosing pipeline.

[0008] Preferably, the electrocoagulation reaction zone includes a reaction tank and a DC power supply. An anode plate and a cathode plate are installed inside the reaction tank, and the positive and negative output terminals of the DC power supply are electrically connected to the anode plate and the cathode plate, respectively, via cables.

[0009] Preferably, the modified biochar adsorption tower includes a tower body and a backwashing device. The interior of the tower body is filled with aluminum modified biochar packing material, and the backwashing device is connected to the tower body through a backwashing inlet pipe and a backwashing outlet pipe.

[0010] Preferably, the regenerated liquid outlet of the backwashing device is connected to the electrocoagulation reaction zone and the wastewater equalization tank respectively through a return pipe.

[0011] Preferably, the sludge separation unit includes an inclined plate sedimentation tank and a sludge thickening tank. The third pipe of the inclined plate sedimentation tank is connected to the modified biochar adsorption tower. The sludge thickening tank is connected to the inclined plate sedimentation tank through a sludge discharge pipe. A clear water zone is provided above the inclined plate sedimentation tank, and a sludge discharge outlet is provided at the bottom of the sludge thickening tank.

[0012] Preferably, the fluoride-containing wastewater is introduced into the inlet unit for water quality adjustment, the wastewater is introduced into the electrocoagulation reaction zone through the first pipe for electrocoagulation reaction, the electrocoagulation reaction zone is introduced into the modified biochar adsorption tower through the second pipe for deep adsorption, and the adsorption tower is introduced into the sludge separation unit through the third pipe for sludge-water separation.

[0013] Preferably, the pH sensor monitors the water quality, and the control unit controls the dosing pump to add chemicals to adjust the pH value of the wastewater to 6-7.

[0014] Preferably, the aluminum-modified biochar filler has a particle size of 2–5 mm.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows: By combining the electrocoagulation unit with the modified biochar adsorption tower, the effluent fluoride concentration can be stably reduced to below 1.0 mg / L. At the same time, through the cooperation of the intelligent control unit and various execution units, the device parameters can be automatically optimized and adjusted, significantly improving the system's resistance to shock loads and ensuring stable and efficient operation of the treatment process. Through the cyclical cooperation of the adsorption unit and the regeneration device, the adsorbent can be efficiently regenerated and utilized. Through the internal circulation of the regenerated liquid, pollutants can be concentrated and recovered, significantly reducing sludge production. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the advanced treatment device for fluoride-containing wastewater according to this utility model.

[0018] In the diagram: 1. PLC controller; 2. Wastewater equalization tank; 3. pH sensor; 4. Dosing pump; 5. DC power supply; 6. Anode plate; 7. Cathode plate; 8. Reaction tank; 9. Aluminum-modified biochar packing; 10. Backwashing device; 11. Inclined plate sedimentation tank; 12. Sludge thickening tank; 13. Clear water zone. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] Example: Figure 1 As shown, this utility model provides a deep treatment device for fluoride-containing wastewater, including a control unit, an inlet unit, an electrocoagulation reaction zone, a modified biochar adsorption tower, and a sludge separation unit. The control unit is connected to the inlet unit and the electrocoagulation reaction zone via a signal line. The inlet unit is provided with a raw water inlet. The electrocoagulation reaction zone is connected to the inlet unit via a first connecting pipe. The modified biochar adsorption tower is connected to the electrocoagulation reaction zone via a second pipe. The sludge separation unit is connected to the modified biochar adsorption tower via a third pipe. By modularly integrating and sequentially connecting the control unit, influent unit, electrocoagulation reaction zone, modified biochar adsorption tower, and sludge separation unit, a foundation for synergistic treatment is constructed. The signal connection between the control unit, influent unit, and electrocoagulation reaction zone enables intelligent system control, while the sequential connection of each treatment unit through pipelines ensures the continuity and stability of the process. This systematic design effectively complements the efficient flocculation effect of electrocoagulation with the deep adsorption function of biochar, overcoming the shortcomings of insufficient removal efficiency of low-concentration fluoride by electrocoagulation alone, and significantly improving the overall reliability of the system operation and the stability of the treatment effect, providing a system guarantee for the effluent fluoride concentration to remain below 1.0 mg / L.

[0021] The control unit includes a PLC controller 1, which is installed in a control cabinet. The PLC controller 1 is connected to the inlet water unit, the electrocoagulation reaction zone, and the modified biochar adsorption tower via signal lines. The inlet water unit includes a wastewater equalization tank 2, inside which a pH sensor 3 is installed. A dosing pump 4 is also installed inside the wastewater equalization tank 2 and connected to it via a dosing pipeline. The electrocoagulation reaction zone includes a reaction tank 8 and a DC power supply 5. An anode plate 6 and a cathode plate 7 are installed inside the reaction tank 8. The positive and negative output terminals of the DC power supply 5 are electrically connected to the anode plate 6 and cathode plate 7 via cables. The modified biochar adsorption tower includes a tower body and a backwashing device 10. The tower body is filled with aluminum modified biochar packing material 9. The backwashing device 10 is connected to the tower body via a backwash inlet pipe and a backwash outlet pipe. Through centralized control of the pH sensor 3, dosing pump 4, DC power supply 5, and other actuators by the PLC controller 1, precise adjustment of device parameters and optimized management of system operation are achieved. The combination of pH sensor 3 and dosing pump 4 keeps the pH of the influent stable within the optimal reaction range of electrocoagulation 6-7. The electrical connection between DC power supply 5 and anode plate 6 and cathode plate 7 provides stable electrolysis conditions for efficient electrocoagulation. The aluminum modified biochar packing 9 with a specific particle size filled in the modified biochar adsorption tower has both good hydraulic properties and high adsorption capacity. Its combination with backwashing device 10 lays the foundation for adsorbent regeneration and circulation while achieving deep defluorination, effectively extending the service life of materials and reducing operating costs.

[0022] The regenerated liquid outlet of the backwashing device 10 is connected to the electrocoagulation reaction zone and the wastewater equalization tank 2 via return pipes. The sludge separation unit includes an inclined plate sedimentation tank 11 and a sludge thickening tank 12. The inclined plate sedimentation tank 11 is connected to the modified biochar adsorption tower via a third pipe, and the sludge thickening tank 12 is connected to the inclined plate sedimentation tank 11 via a sludge discharge pipe. A clear water zone 13 is located above the inclined plate sedimentation tank 11, and a sludge discharge outlet is located at the bottom of the sludge thickening tank 12. Fluoride-containing wastewater is introduced into the inlet unit for water quality adjustment. The wastewater is introduced into the electrocoagulation reaction zone via a first pipe for electrocoagulation reaction. The electrocoagulation reaction zone is introduced into the modified biochar adsorption tower via a second pipe for deep adsorption. The adsorption tower is introduced into the sludge separation unit via a third pipe for sludge-water separation. A pH sensor 3 monitors the water quality, and a control unit controls the dosing pump 4 to add chemicals, adjusting the pH of the wastewater to the specified level. 6-7. The aluminum-modified biochar packing has a particle size of 2-5mm. The regenerated liquid is returned to the electrocoagulation reaction zone or wastewater equalization tank 2 through the backwashing device 10. This design realizes closed-loop treatment and potential resource recovery for the adsorption and enrichment of fluorides. While improving the fluoride removal rate, it avoids secondary pollution. The efficient solid-liquid separation of the inclined plate sedimentation tank 11 and the sludge thickening tank 12 ensures the quality of the effluent. The setting of the sludge discharge outlet realizes the standardized disposal of sludge. Under the intelligent scheduling of the PLC controller 1, the entire system, through the organic integration of the functions of each unit, not only ensures the stable achievement of the deep fluoride removal target, but also realizes the comprehensive environmental benefits of sludge reduction, energy consumption reduction and resource reuse. It provides an efficient and reliable solution for the treatment of industrial fluoride-containing wastewater.

[0023] Working principle: Fluoride-containing wastewater first enters the wastewater equalization tank 2 of the inlet unit. The pH sensor 3 installed in the tank monitors the water quality parameters in real time, and the monitoring data is transmitted to the PLC controller 1 in real time. The controller intelligently adjusts the dosage of the dosing pump 4 according to the preset program to precisely adjust the pH of the wastewater to the optimal reaction range of 6-7, creating ideal conditions for the subsequent electrocoagulation process. The pretreated wastewater enters the reaction tank 8 of the electrocoagulation reaction zone through the first pipe. Under the action of the DC power supply 5, an electric field is formed between the anode plate 6 and the cathode plate 7. The anode plate 6 undergoes an electrolytic reaction to continuously generate aluminum ions. These ions combine with hydroxyl groups in the water to form aluminum-based flocculants with strong adsorption properties. The initial removal of fluoride ions is achieved through charge neutralization, adsorption bridging and other effects. Subsequently, the wastewater containing fluoride flocs enters the modified biochar adsorption tower through the second pipe. The aluminum modified biochar packing 9 with a specific particle size of 2-5 mm filled in the tower uses its rich microporous structure and surface-loaded active aluminum components to specifically adsorb and exchange residual fluoride ions, achieving deep purification. This stage effectively solves the problem of insufficient removal efficiency of low-concentration fluoride by electrocoagulation. After deep purification, the wastewater enters the sludge separation unit through the third pipe. In the inclined plate sedimentation tank 11, the flocs and the supernatant are efficiently separated by the principle of shallow sedimentation. The supernatant is discharged through the upper clear water zone 13 in compliance with standards. The sludge generated by sedimentation enters the sludge thickening tank 12 through the sludge discharge pipe for further thickening and volume reduction treatment. Finally, it is discharged from the system through the bottom sludge discharge port. At the same time, when the biochar adsorption is detected to be saturated, the backwashing device 10 is started for regeneration. The packing is washed and regenerated with a specific concentration of alkaline solution. The fluoride-rich regenerated liquid is returned to the electrocoagulation reaction zone or equalization tank through the return pipe to realize the recycling treatment and resource recovery of fluoride. Under the intelligent scheduling of PLC controller 1, the entire system ensures that the effluent fluoride concentration is consistently below 1.0 mg / L through real-time monitoring and coordinated control of the operating parameters of each unit. It also achieves effective control of operating costs through resource recycling, providing a complete technical solution for the deep treatment of fluoride-containing wastewater.

[0024] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.

Claims

1. A deep treatment device for fluoride-containing wastewater, comprising a control unit, an influent unit, an electrocoagulation reaction zone, a modified biochar adsorption tower, and a sludge separation unit, characterized in that, The control unit is connected to the water inlet unit and the electrocoagulation reaction zone via a signal line. The water inlet unit is equipped with a raw water inlet. The electrocoagulation reaction zone is connected to the water inlet unit via a first connecting pipe. The modified biochar adsorption tower is connected to the electrocoagulation reaction zone via a second pipe. The sludge separation unit is connected to the modified biochar adsorption tower via a third pipe.

2. The advanced treatment device for fluoride-containing wastewater as described in claim 1, characterized in that, The control unit includes a PLC controller (1), which is installed in the control cabinet. The PLC controller (1) is connected to the water inlet unit, the electrocoagulation reaction zone and the modified biochar adsorption tower via signal lines.

3. The advanced treatment device for fluoride-containing wastewater as described in claim 1, characterized in that, The water inlet unit includes a wastewater equalization tank (2), a pH sensor (3) is installed inside the wastewater equalization tank (2), and a dosing pump (4) is installed inside the wastewater equalization tank (2). The dosing pump (4) is connected to the wastewater equalization tank (2) through a dosing pipeline.

4. The advanced treatment device for fluoride-containing wastewater as described in claim 1, characterized in that, The electrocoagulation reaction zone includes a reaction tank (8) and a DC power supply (5). An anode plate (6) and a cathode plate (7) are installed inside the reaction tank (8). The positive and negative output terminals of the DC power supply (5) are electrically connected to the anode plate (6) and the cathode plate (7) respectively via cables.

5. The advanced treatment device for fluoride-containing wastewater as described in claim 1, characterized in that, The modified biochar adsorption tower includes a tower body and a backwashing device (10). The tower body is filled with aluminum modified biochar packing material (9). The backwashing device (10) is connected to the tower body through a backwashing inlet pipe and a backwashing outlet pipe.

6. The advanced treatment device for fluoride-containing wastewater as described in claim 5, characterized in that, The regenerated liquid outlet of the backwashing device (10) is connected to the electrocoagulation reaction zone and the wastewater regulating tank (2) respectively through the return pipe.

7. The advanced treatment device for fluoride-containing wastewater as described in claim 1, characterized in that, The sludge separation unit includes an inclined plate sedimentation tank (11) and a sludge thickening tank (12). The third pipe of the inclined plate sedimentation tank (11) is connected to the modified biochar adsorption tower. The sludge thickening tank (12) is connected to the inclined plate sedimentation tank (11) through a sludge discharge pipe. A clear water zone (13) is provided above the inclined plate sedimentation tank (11), and a sludge discharge port is provided at the bottom of the sludge thickening tank (12).

8. The advanced treatment device for fluoride-containing wastewater as described in claim 1, characterized in that, The fluoride-containing wastewater is introduced into the inlet unit for water quality adjustment. The wastewater is introduced into the electrocoagulation reaction zone through the first pipe for electrocoagulation reaction. The electrocoagulation reaction zone is introduced into the modified biochar adsorption tower through the second pipe for deep adsorption. The adsorption tower is introduced into the sludge separation unit through the third pipe for sludge-water separation.

9. The advanced treatment device for fluoride-containing wastewater as described in claim 3, characterized in that, The pH sensor (3) monitors the water quality, and the control unit controls the dosing pump (4) to add chemicals and adjust the pH value of the wastewater to 6-7.

10. The advanced treatment device for fluoride-containing wastewater as described in claim 5, characterized in that, The particle size of the aluminum-modified biochar filler (9) is 2–5 mm.

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