Fluorine-containing wastewater high-precision treatment and resource utilization system

Abstract

The invention relates to the technical field of fluorine-containing wastewater treatment devices, and discloses a fluorine-containing wastewater high-precision treatment and resource utilization system. Comprising an adsorption-separation-regeneration-cyclic utilization system and a PLC automatic control system, a base is arranged at one end of the adsorption-separation-regeneration-cyclic utilization system, an adsorption device is installed on one side of the upper surface of the base, a water inlet is formed in one end of the adsorption device, and a water outlet is formed in one end of the adsorption device; an adsorption device is arranged on the upper surface of the base, a separation recovery-cyclic utilization device is mounted at the upper end of the adsorption device, a regeneration device is arranged on the upper surface of the base, a filtering device is arranged at one end of the regeneration device, and a sediment collection box is arranged at one end of the upper surface of the base. According to the present invention, the efficient fluorine removal effect can be achieved, and the fluorine ion concentration in the wastewater is reduced to less than 1 mg / L, such that the efficiency problem of the traditional method in the low-concentration fluorine wastewater treatment is solved, and the strict discharge standard of the wastewater can be ensured.

Description

Technical Field

[0001] The present invention belongs to the technical field of fluorine-containing wastewater treatment equipment, and specifically relates to a high-precision treatment and resource utilization system for fluorine-containing wastewater. Background Art

[0002] Fluoride-containing wastewater mainly comes from fluoride salt production, electrolytic aluminum industry, glass manufacturing, electronic semiconductors, surface treatment and refrigerant production industries. The fluoride ion concentration in these wastewaters is as high as 100-1000 mg / L, which is highly corrosive and toxic, and has great potential harm to water bodies, soil environment and human body.

[0003] The existing methods for treating fluoride-containing wastewater are mainly chemical precipitation, coagulation precipitation and adsorption. The chemical precipitation method converts fluoride ions into calcium fluoride precipitates by adding lime or calcium chloride, and the coagulation precipitation method generates floccules by adding coagulants such as aluminum salts and iron salts to adsorb fluoride ions. These methods have good treatment effects on high-concentration fluoride-containing wastewater, but the fluoride removal accuracy is low. The fluoride ion content of the effluent is generally around 20 mg / L, which is difficult to meet the fluoride ion emission limit (≤10 mg / L) specified in the "Comprehensive Sewage Discharge Standard" (GB 8978-1996). It is also easy to produce a large amount of sludge, which may cause secondary pollution and increase the difficulty of subsequent treatment. The adsorption method uses the active sites on the surface of adsorbents such as activated alumina, activated carbon, and hydroxyapatite to adsorb fluoride ions. The efficiency of fluoride removal is high and a low residual fluoride concentration can be achieved. The fluoride ion concentration of the treated wastewater can be reduced to below 1 mg / L, which can meet the accuracy requirements for fluoride-containing wastewater treatment. In addition, compared with other methods, the adsorption method usually does not require complex equipment and operating processes. The equipment is simple and easy to maintain, the cost is low, and it is suitable for various types of fluoride-containing wastewater and treatment facilities of various sizes.

[0004] However, existing adsorption methods generally have problems such as easy loss of adsorption materials, difficulty in separation, difficulty in regeneration after saturation, complex and time-consuming and energy-consuming regeneration process, easy secondary pollution caused by the regeneration process, and low degree of automation of the adsorption equipment. Summary of the invention

[0005] The purpose of the present invention is to provide a high-precision treatment and resource utilization system for fluorine-containing wastewater in order to solve the problems commonly existing in the above-mentioned existing adsorption methods, such as easy loss of adsorbent materials, difficulty in separation, difficulty in regeneration after saturation, complex and time-consuming and energy-consuming regeneration process, easy secondary pollution caused by the regeneration process, and low degree of automation of the adsorption equipment.

[0006] The technical solution adopted by the present invention is as follows: a high-precision treatment and resource utilization system for fluorine-containing wastewater, including an adsorption-separation-regeneration-recycling system and a PLC automatic control system, one end of the adsorption-separation-regeneration-recycling system is provided with a base, one side of the upper surface of the base is provided with an adsorption device, one end of the adsorption device is provided with a water inlet, one end of the adsorption device is provided with a water outlet, the upper end of the adsorption device is provided with a separation recovery-recycling device, one end of the separation recovery-recycling device is provided with a servo motor, the upper end of the servo motor is provided with a rotating shaft, the separation recovery-recycling device is provided with a servo motor, and the separation recovery-recycling device is provided with a servo motor. A square rotating plate is arranged at the lower end of the device, a through circular opening corresponding to the circular hole is provided on the surface of the square rotating plate, a plurality of separation and recovery devices corresponding to the through circular opening are installed on the upper surface of the square rotating plate, a semicircular hole is provided at one end of the square rotating plate, one side of the semicircular hole is welded to the outer surface of the rotating shaft, a triangular bracket corresponding to the rotating shaft is arranged on one side of the square rotating plate, the triangular bracket is connected to the rotating shaft, a regeneration device is arranged on the upper surface of the base, a filtering device is arranged at one end of the regeneration device, and a sedimentation collection box is arranged at one end of the upper surface of the base.

[0007] By adopting the above technical solution, using magnetic adsorption materials and an optimized adsorption-separation-regeneration-recycling system, it is possible to achieve efficient fluoride removal and reduce the fluoride ion concentration in the wastewater to below 1 mg / L. This not only solves the efficiency problem of traditional methods in the treatment of low-concentration fluoride wastewater, but also ensures that the wastewater meets strict emission standards.

[0008] In a preferred embodiment, a cylindrical adsorption tank is arranged inside the adsorption device, eight circular holes are opened at the upper end of the adsorption device, a baffle is arranged inside the adsorption tank, a primary adsorption tank and a secondary adsorption tank are arranged on both sides of the adsorption tank, the baffle is arranged in the middle of the primary adsorption tank and the secondary adsorption tank, and two stirring devices are installed inside the primary adsorption tank and the secondary adsorption tank.

[0009] By adopting the above technical solution, the stirring device adopts a mechanical stirring form, which can improve the contact efficiency between the magnetic adsorption material and the fluoride ions in the wastewater, prevent the adsorption material from settling or agglomerating, and ensure its uniform distribution.

[0010] In a preferred embodiment, a motor a is installed at one end of the stirring device, a rotating rod is provided at one end of the motor a, stirring rods are provided on both sides of one end of the rotating rod, three stirring blades a are provided on the outer surface of the stirring rod, and the inclination angle between the stirring blades a is set to 120°, a driving gear is provided on the outer surface of the rotating rod, and a driven gear corresponding to the driving gear is provided on the outer surface of the stirring rod on one side, the driving gear is meshed with the driven gear, and three stirring blades b are provided on the outer surface of the bottom end of the rotating rod.

[0011] By adopting the above technical solution, after the motor a is energized, the rotating rod drives the stirring rod, the driving gear and the stirring blade a to rotate horizontally around the rotating rod, the driving gear then drives the driven gear, and the driven gear drives the stirring blade a to rotate around the stirring rod, so that the stirring blade can not only rotate horizontally but also rotate vertically, so that the adsorption material can be fully dispersed in the adsorption tank.

[0012] In a preferred embodiment, a cylindrical regeneration tank of the same shape as the adsorption device is arranged inside the regeneration device, eight circular holes are opened on the top of the regeneration device, the stirring device is installed on the inner wall of the upper end of the regeneration device, a flushing device is installed inside the regeneration device, four pointed nozzles are arranged inside the flushing device, the pointed nozzles are arranged at the lower ends of the circular holes, and the nozzles are 60° toward the direction of the circular holes, and a dosing device a and a dosing device b are respectively installed on both sides of the upper end of the regeneration device.

[0013] By adopting the above technical scheme, deionized water is sprayed to wash the regeneration reagent remaining on the surface of the magnetic adsorption material, and the dosing device a adds the regeneration reagent to desorb the magnetic adsorption material that adsorbs fluoride ions, so that the fluoride ions are transferred to the solution without changing the surface chemical properties of the magnetic material. The dosing device b adds the concentration reagent to separate the fluoride ions in the regeneration solution through precipitation, and then the fluoride ion precipitate is finally recovered into the precipitation collection box through the filtering device to realize resource utilization.

[0014] In a preferred embodiment, a disc is provided inside the separation and recovery device, a motor b is installed on one side of the upper surface of the disc, a barrel wheel is provided on the upper end of the motor b, an arc-shaped groove is provided on the outer surface of the barrel wheel, a cylindrical slider is slidably connected inside the arc-shaped groove, a box body corresponding to the motor b is provided on one side of the upper surface of the disc, a right groove is provided on one side surface of the box body, the cylindrical slider is slidably connected inside the right groove, the circular hole is provided in the middle of the disc, a hollow cylindrical bottom tube corresponding to the circular hole is provided on the lower surface of the disc, and hydraulic rods are installed on four sides of the lower surface of the disc.

[0015] By adopting the above technical solution, under the action of motor b, the barrel wheel can be driven to rotate, so that one end of the columnar slider slides inside the arc-shaped slide groove, and then the columnar slider can be driven to move inside the right groove.

[0016] In a preferred embodiment, a spring is installed inside the box, a magnet is arranged inside the spring, a disc pressure block is arranged on the upper end of the magnet, rectangular sliders are arranged on both sides of the disc pressure block, the columnar slider is arranged on the surface of one side of the rectangular slider, and a left groove corresponding to the rectangular slider is opened on the other side surface of the box.

[0017] By adopting the above technical solution, after the motor b is energized, it drives the barrel wheel to rotate, and the cylindrical slider overlapped on the inside of the arc-shaped slide groove on the barrel wheel slides downward, and the cylindrical slider drives the spring and the magnet to move downward, pushing the magnet into the interior of the hollow cylindrical bottom tube through the circular hole, and then the hydraulic rod contracts, causing the hollow cylindrical bottom tube structure with the magnet to descend and be pushed into the adsorption device or regeneration device.

[0018] In a preferred embodiment, the magnet is made of neodymium iron boron magnet.

[0019] By adopting the above technical solution, it has good magnetism and can provide strong magnetic field support. At the same time, it has good wear resistance and scratch resistance, which prolongs its service life.

[0020] In a preferred embodiment, a sedimentation bin is provided at the lower end of the interior of the filter device, a filtrate bin is provided at the upper end of the interior of the filter device, a filter screen is provided between the sedimentation bin and the filtrate bin, a mud suction pipe is provided at one end of the filter device, the mud suction pipe is connected to the regeneration device, a sedimentation discharge pipe is provided at one end of the filter device, the sedimentation discharge pipe is connected to the sedimentation collection box, a return pipe is provided at the upper end of the filter device, the other end of the return pipe is connected to the regeneration device, and a pump is installed at one end of the return pipe, the mud suction pipe and the sedimentation discharge pipe.

[0021] By adopting the above technical solution, under the action of the pump, the precipitate of the regeneration device is pumped into the sedimentation bin, the liquid filtered through the filter screen flows into the filtrate bin, and then flows back to the regeneration device through the reflux pipe, and the CaF2 precipitate in the sedimentation bin enters the sedimentation collection box for storage through the sedimentation discharge pipe.

[0022] In a preferred embodiment, the PLC automatic control system is provided with fluorine ion sensors in the water inlet, the water outlet and the regeneration device of the adsorption device, respectively, and a conductivity sensor is provided in the regeneration device.

[0023] By adopting the above technical solution, real-time monitoring of F - The key parameters such as concentration and ionic strength of NaCl regenerant are controlled automatically to realize the full automatic control of adsorption, regeneration, precipitation and discharge, thus ensuring the efficient and stable operation of the defluorination system.

[0024] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0025] 1. The present invention adopts magnetic adsorption materials and an optimized adsorption-separation-regeneration-recycling system, which can achieve efficient fluoride removal and reduce the fluoride ion concentration in the wastewater to below 1 mg / L. It not only solves the efficiency problem of traditional methods in the treatment of low-concentration fluoride wastewater, but also ensures that the wastewater meets strict emission standards.

[0026] 2. The present invention optimizes the design of the adsorption material and adopts magnetic adsorption material, which significantly reduces the loss and separation problems of traditional adsorption materials, and realizes gradient adsorption through a two-stage adsorption design, thereby improving the stability of the adsorption material, extending its service life, avoiding frequent replenishment or replacement of the adsorption material, and thus reducing the processing cost.

[0027] 3. The present invention organically combines the adsorption device with the regeneration device to form an efficient and rapid in-situ regeneration system. The system avoids the complex, energy-intensive and manual intervention-dependent operations in traditional regeneration technologies, greatly improves the regeneration efficiency of the adsorption material, reduces the waste of adsorption materials, and reduces the cost of the entire wastewater treatment process.

[0028] 4. The present invention converts F in the regeneration liquid - It is converted into calcium fluoride precipitation and collected. As a usable resource, CaF2 can be used in many industrial fields, which not only avoids the - It can reduce secondary pollution to the environment and ensure the environmental friendliness of the wastewater treatment process, thereby improving the greenness and sustainability of the wastewater treatment process.

[0029] 5. The present invention automates key operations such as adsorption, separation and regeneration of adsorbent materials, reduces human intervention and uncertainty factors, and improves the flexibility and stability of the system. Automated control not only improves operational efficiency, but also reduces human operational errors and costs, making the entire wastewater treatment process more efficient and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is an overall schematic diagram of the system for high-precision treatment and resource utilization of fluorine-containing wastewater in the present invention;

[0031] Figure 2 It is a front structural schematic diagram of the adsorption-separation-regeneration-recycling system of the present invention;

[0032] Figure 3 It is a cross-sectional view of the adsorption-separation-regeneration-recycling system of the present invention;

[0033] Figure 4 It is a front structural schematic diagram of the stirring device in the present invention;

[0034] Figure 5 It is a front structural schematic diagram of the separation and recovery device in the present invention;

[0035] Figure 6 It is a front structural cross-sectional view of the separation and recovery device of the present invention;

[0036] Figure 7 It is a rear structural cross-sectional view of the separation and recovery device of the present invention;

[0037] Figure 8 It is a cross-sectional view of the filtering device in the present invention.

[0038] Markings in the figure: 1. Adsorption-separation-regeneration-recycling system; 2. PLC automatic control system; 3. Base; 4. Water inlet; 5. Adsorption device; 6. Separation recovery-recycling device; 7. Regeneration device; 8. Filter device; 9. Sediment collection box; 10. Water outlet; 11. Servo motor; 12. Triangular bracket; 13. Rotating shaft; 14. Square rotating plate; 15. Separation recovery device; 16. Round hole; 17. Dosing device a; 18. Dosing device b; 19. Mud suction pipe; 20. Pump; 21. Reflux pipe; 22. Sediment discharge pipe; 23. Baffle; 24. Primary adsorption tank; 25 , secondary adsorption tank; 26, stirring device; 27, flushing device; 28, filter screen; 29, motor a; 30, rotating rod; 31, driving gear; 32, driven gear; 33, stirring rod; 34, stirring blade a; 35, stirring blade b; 36, hollow cylindrical bottom tube; 37, hydraulic rod; 38, disc; 39, motor b; 40, barrel wheel; 41, arc-shaped slide; 42, box; 43, columnar slider; 44, right groove; 45, spring; 46, magnet; 47, round cake block; 48, rectangular slider; 49, left groove; 50, sedimentation bin; 51, filtrate bin. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] Reference Figure 1-8 A high-precision treatment and resource utilization system for fluorine-containing wastewater, comprising an adsorption-separation-regeneration-recycling system 1 and a PLC automatic control system 2, wherein a base 3 is provided at one end of the adsorption-separation-regeneration-recycling system 1, an adsorption device 5 is installed on one side of the upper surface of the base 3, a water inlet 4 is provided at one end of the adsorption device 5, a water outlet 10 is provided at one end of the adsorption device 5, a separation recovery-recycling device 6 is installed at the upper end of the adsorption device 5, a servo motor 11 is installed at one end of the separation recovery-recycling device 6, a rotating shaft 13 is provided at the upper end of the servo motor 11, a square rotating plate 14 is provided at the lower end of the separation recovery-recycling device 6, a through circular opening corresponding to the circular hole 16 is opened on the surface of the square rotating plate 14, and a plurality of through circular openings corresponding to the circular hole 16 are installed on the upper surface of the square rotating plate 14 A separation and recovery device 15 corresponding to the through-type circular opening is provided, a semicircular hole is provided at one end of the square rotating plate 14, one side of the semicircular hole is welded to the outer surface of the rotating shaft 13, a triangular bracket 12 corresponding to the rotating shaft 13 is provided on one side of the square rotating plate 14, the triangular bracket 12 is connected to the rotating shaft 13, a regeneration device 7 is provided on the upper surface of the base 3, a filtering device 8 is provided at one end of the regeneration device 7, and a sedimentation collection box 9 is provided at one end of the upper surface of the base 3. Through the above design, the use of magnetic adsorption materials and an optimized adsorption-separation-regeneration-recycling system can achieve efficient fluoride removal effect and reduce the fluoride ion concentration in the wastewater to below 1 mg / L, which not only solves the efficiency problem of traditional methods in the treatment of low-concentration fluoride wastewater, but also ensures that the wastewater meets strict emission standards.

[0041] Reference Figure 2-4 A cylindrical adsorption tank is arranged inside the adsorption device 5, eight circular holes 16 are opened at the upper end of the adsorption device 5, a baffle 23 is arranged inside the adsorption tank, a primary adsorption tank 24 and a secondary adsorption tank 25 are arranged on both sides of the adsorption tank, the baffle 23 is arranged in the middle of the primary adsorption tank 24 and the secondary adsorption tank 25, two stirring devices 26 are installed inside the primary adsorption tank 24 and the secondary adsorption tank 25, and the stirring device 26 adopts a mechanical stirring form, which can improve the contact efficiency between the magnetic adsorption material and the fluoride ions in the wastewater, prevent the adsorption material from settling or agglomerating, and ensure its uniform distribution.

[0042] Reference Figure 4, a motor a29 is installed at one end of the stirring device 26, a rotating rod 30 is arranged at one end of the motor a29, stirring rods 33 are arranged on both sides of one end of the rotating rod 30, and three stirring blades a34 are arranged on the outer surface of the stirring rod 33, and the inclination angle between the stirring blades a34 is set to 120°, a driving gear 31 is arranged on the outer surface of the rotating rod 30, and a driven gear 32 corresponding to the driving gear 31 is arranged on the outer surface of the stirring rod 33 on one side, and the driving gear 31 is meshed with the driven gear 32, and three stirring blades b35 are arranged on the outer surface of the bottom end of the rotating rod 30. After the motor a29 is energized, the rotating rod 30 drives the stirring rod 33, the driving gear 31 and the stirring blade a34 to rotate horizontally around the rotating rod 30, and the driving gear 31 then drives the driven gear 32, and the driven gear 32 drives the stirring blade a34 to rotate around the stirring rod 33, thereby realizing that the stirring blade can not only rotate horizontally, but also rotate vertically, so that the adsorption material can be fully dispersed in the adsorption tank.

[0043] Reference Figure 2-4 The regeneration device 7 is provided with an adsorption pool which is the same as the adsorption device 5. Eight circular holes 16 are provided on the top of the regeneration device 7. A stirring device 26 is installed on the inner wall of the upper end of the regeneration device 7. A flushing device 27 is installed inside the regeneration device 7. Four pointed nozzles are arranged inside the flushing device 27. The pointed nozzles are arranged at the lower end of the circular hole 16. The nozzles are 60° toward the circular hole 16. A dosing device a17 and a dosing device b18 are installed on both sides of the upper end of the regeneration device 7. The regeneration reagent remaining on the surface of the magnetic adsorption material is washed by spraying deionized water. The dosing device a17 adds the regeneration reagent to desorb the magnetic adsorption material that adsorbs fluoride ions, so that the fluoride ions are transferred to the solution without changing the surface chemical properties of the magnetic material. The dosing device b18 adds the concentrated reagent to separate the fluoride ions in the regeneration solution by precipitation. The fluoride ion precipitate is finally recovered into the precipitation collection box 9 through the filtering device 8 to realize resource utilization.

[0044] Reference Figure 2-Figure 3 and Figure 5-Figure 7A disc 38 is provided inside the separation and recovery device 15, and a motor b39 is installed on one side of the upper surface of the disc 38. A barrel wheel 40 is provided on the upper end of the motor b39. An arc-shaped slide groove 41 is provided on the outer surface of the barrel wheel 40. A columnar slider 43 is slidably connected inside the arc-shaped slide groove 41. A box body 42 corresponding to the motor b39 is provided on one side of the upper surface of the disc 38. A right groove 44 is provided on one side of the box body 42. The columnar slider 43 is slidably connected inside the right groove 44. A circular hole 16 is provided in the middle of the disc 38. A hollow cylindrical bottom tube 36 corresponding to the circular hole 16 is provided on the lower surface of the disc 38. Hydraulic rods 37 are installed on four sides of the lower surface of the disc 38. Under the action of the motor b39, the barrel wheel 40 can be driven to rotate, so that one end of the columnar slider 43 slides inside the arc-shaped slide groove 41, and then the columnar slider 43 can be driven to move inside the right groove 44.

[0045] Reference Figure 6-7 A spring 45 is installed inside the box 42, and a magnet 46 is arranged inside the spring 45. A round cake pressing block 47 is arranged on the upper end of the magnet 46. Rectangular sliders 48 are arranged on both sides of the round cake pressing block 47. A columnar slider 43 is arranged on the surface of the rectangular slider 48 on one side. A left groove 49 corresponding to the rectangular slider 48 is opened on the other side surface of the box 42. After the motor b39 is energized, it drives the barrel wheel 40 to rotate, and the columnar slider 43 overlapped on the arc-shaped slide groove 41 on the barrel wheel 40 slides downward accordingly. The columnar slider 43 drives the spring 45 and the magnet 46 to move downward, and pushes the magnet 46 into the interior of the hollow cylindrical bottom tube 36 through the circular hole 16. Then the hydraulic rod 37 contracts, so that the hollow cylindrical bottom tube structure with the magnet descends and is pushed into the adsorption device 5 or the regeneration device 7.

[0046] Reference Figure 6-7 The material of magnet 46 is neodymium iron boron magnet N52, which has good magnetic properties and can provide strong magnetic field support. At the same time, it has good wear resistance and scratch resistance, which prolongs its service life.

[0047] Reference Figure 2-3 and Figure 8A sedimentation bin 50 is provided at the lower end of the interior of the filter device 8, a filtrate bin 51 is provided at the upper end of the interior of the filter device 8, a filter screen 28 is provided between the sedimentation bin 50 and the filtrate bin 51, a sludge suction pipe 19 is provided at one end of the filter device 8, and the sludge suction pipe 19 is connected to the regeneration device 7, a sedimentation discharge pipe 22 is provided at one end of the filter device 8, and the sedimentation discharge pipe 22 is connected to the sedimentation collection box 9, a return pipe 21 is provided at the upper end of the filter device 8, and the other end of the return pipe 21 is connected to the regeneration device 7, and a pump 20 is installed at one end of the return pipe 21. Under the action of the pump 20, the sediment of the regeneration device 7 is pumped into the sedimentation bin 50, and the liquid filtered by the filter screen 28 flows into the filtrate bin 51, and then flows back to the regeneration device 7 through the reflux pipe 21, and the CaF2 precipitate in the sedimentation bin 50 enters the sedimentation collection box 9 for storage through the sedimentation discharge pipe 22.

[0048] Reference Figure 1-8 The PLC automatic control system 2 is provided with fluoride ion sensors in the water inlet 4, the water outlet 10 of the adsorption device 5 and the regeneration device 7, and a conductivity sensor is also provided in the regeneration device 7 to monitor the F in real time. - The key parameters such as concentration and ionic strength of NaCl regenerant are controlled automatically to realize the full automatic control of adsorption, regeneration, precipitation and discharge, thus ensuring the efficient and stable operation of the defluorination system.

[0049] The implementation principle of the embodiment of the fluorine-containing wastewater high-precision treatment and resource utilization system of the present invention is:

[0050] When the system is started, the PLC controls the water inlet to open, so that the pretreated fluorine-containing wastewater enters the adsorption device 5 from the water inlet, first flows through the primary adsorption tank 24, and is fully contacted with the magnetic adsorption material in the primary adsorption tank under the action of the stirring device 26. Under the action of physical or chemical adsorption, the fluorine-containing wastewater combines with a large number of holes and active sites on the surface of the magnetic adsorption material, and completes the preliminary adsorption of the fluorine-containing wastewater in the primary adsorption tank. Then, it enters the secondary adsorption tank 25 through the baffle 23, and is fully contacted with the magnetic adsorption material in the secondary adsorption tank under the action of the stirring device 26, and the fluorine in the wastewater is further thoroughly adsorbed in the secondary adsorption tank. - This graded adsorption method can achieve gradient adsorption, improve adsorption efficiency, and prevent F - The saturation of magnetic adsorption materials caused by excessive adsorption prolongs the service life of the magnetic adsorption materials, thereby improving the effect of the entire adsorption device in removing fluoride ions. -After the concentration reaches the standard, the PLC controls the adsorption device to stop running and discharge the water quality that meets the standard. If the fluoride ion concentration monitored at the water outlet continues to exceed the set standard value and lasts for 30 minutes, it is determined that the magnetic adsorption material has reached saturation. At this time, the PLC system controls the water inlet and the adsorption device to be closed, and starts the separation and recovery device 15. The barrel wheel 40 on the square plate rotates with the motor b39, driving the cylindrical slider 43 and the rectangular slider 48 to move downward. The round cake pressing block 47 compresses the spring 45, driving the magnet 46 to move downward through the center hole of the disc 38, and pushing the magnet 46 into the hollow cylindrical bottom tube 36. Then the hydraulic rod 37 contracts, causing the hollow cylindrical bottom tube structure with the magnet to descend and be pushed into the adsorption device 5. The magnetic adsorption material will be completely attracted to the surface of the hollow cylindrical bottom tube 36 by the magnet's attraction. Then the hydraulic rod 37 rises, driving the separation and recovery device 15 to remove the magnetic adsorption material from the adsorption device The servo motor 11 in the separation recovery-recycling device 6 is started to drive the square plate 14 to the top of the regeneration device 7. The circular hole of the square plate corresponds to the circular hole on the surface of the regeneration device. The hydraulic rod 37 contracts to push the hollow cylindrical bottom tube with the magnet and the magnetic adsorption material on its surface into the regeneration device 7. Then the barrel wheel 40 rotates in the opposite direction with the motor b39 to completely extract the magnet 46 from the hollow cylindrical bottom tube 36. The magnetic adsorption material that loses the magnetic attraction falls into the regeneration device 7. Then the hydraulic rod 37 rises to drive the hollow cylindrical bottom tube 36 to return to its original position. The dosing device a17 and the stirring device 26 in the regeneration device 7 are started to add NaCl regeneration agent to start the regeneration process. During this period, if the conductivity reaches 5.8~23 S·m -1 If the conductivity is lower than 5.8 S·m during the regeneration process, the dosing is stopped. -1 , the PLC system will determine that the concentration of NaCl reagent is not enough, and automatically start the dosing device a17 to add reagents until the conductivity reaches the preset range, which can ensure that the regeneration agent is sufficient and the magnetic adsorption material is desorbed more thoroughly. As the regeneration process proceeds, F - It will be desorbed from the magnetic adsorption material into the solution, F - The concentration of F -When the concentration tends to be stable over time and the change range is less than 0.1 mg / L, the system automatically determines that the desorption is completed. After the desorption is completed, the separation and recovery device 15 is started first, and the regenerated magnetic adsorption material is sucked to the surface of the hollow cylindrical bottom tube 36 by the magnetic attraction of the magnet, and then the hydraulic rod 37 is lifted to slowly leave the hollow cylindrical bottom tube from the regeneration liquid surface, and the flushing device 27 is started simultaneously to slowly flush the regeneration liquid remaining on the surface of the magnetic adsorption material, and then the magnetic adsorption material is recovered from the regeneration tank, and then the separation and recovery-recycling device 6 is started, and the separation and recovery-recycling device 6 is rotated to the top of the adsorption device 5, and the regenerated magnetic adsorption material is added to the adsorption device 5 for recycling, and then the separation and recovery device 15 returns to its original position. After multiple regeneration and recovery processes, after the magnetic adsorption material is separated from the regeneration tank, the PLC system detects the F in the regeneration tank. - When the concentration reaches 40mg / L or above, PLC will adjust the concentration according to the actual F - Concentration, by Ca 2 + With F - The molar ratio of 1:2 is used to calculate the amount of CaCl2 required to be added, and the dosing device b18 is started to add CaCl2 agent to react with F in the regeneration liquid. - The reaction generates CaF2 precipitate, which is pumped into the filter device 8 through the mud suction pipe 19. The filtered solution is returned to the regeneration device 7 through the filtration liquid bin 51 and the reflux pipe 21 above the filter device. The precipitate remaining in the precipitation bin 50 is sent to the collection box 9 through the precipitation discharge pipe 22 to be recycled. The CaCl2 precipitate in the collection box 9 is regularly recovered and can be used for various industrial purposes such as fluorination agent in aluminum industry, desulfurization agent in steel smelting, and for manufacturing fluorinated plastics.

[0051] In addition, the magnetic adsorption material was prepared by coprecipitation method, and ferric chloride hexahydrate and ferric sulfate heptahydrate were mixed in a molar ratio of Fe 3+ / Fe 2+ =2:1, add the mixture into the beaker and stir. Nitrogen is continuously introduced into the beaker to prevent Fe 2+ Oxidized to Fe 3+ , improve the purity of Fe3O4, slowly add 3~5mm adsorption materials such as activated alumina, hydroxyapatite, etc. to the iron salt solution, use a magnetic stirrer to stir for 30 minutes to disperse the adsorption materials evenly, use a water bath constant temperature magnetic stirrer, heat the beaker to 60-80℃ in a water bath, and maintain constant temperature stirring, then slowly add 25% ammonia water or 1-2mol / L sodium hydroxide solution to the beaker, adjust the pH of the iron salt solution to 9~11, and make Fe 3+ / Fe 2+Co-precipitate to form Fe3O4 magnetic nanoparticles, observe that the solution gradually turns black, continue stirring for 1-2 hours to ensure that the Fe3O4 magnetic nanoparticles are evenly coated on the surface of the adsorption material. After the reaction is completed, stop stirring and let it stand for 10 minutes to allow the magnetic adsorption material to settle naturally. Use a vacuum filtration device to filter out the magnetic adsorption material, and then wash it with deionized water for 3 to 5 times until the pH of the washing liquid is about 7 to remove residual sodium hydroxide or ammonia water. Place the washed magnetic adsorption material in a vacuum drying oven at 60 to 80°C and dry it for 12 hours, then place it in a muffle furnace and calcine it at 300 to 400°C for 2 hours, cool it to room temperature, and discharge it to obtain a magnetic adsorption material.

[0052] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-precision treatment and resource utilization system for fluorine-containing wastewater, comprising an adsorption-separation-regeneration-circulation system (1) and a PLC automatic control system (2), characterized in that: The adsorption-separation-regeneration-recycling system (1) is provided with a base (3) at one end, an adsorption device (5) is installed on one side of the upper surface of the base (3), eight circular holes (16) are opened at the upper end of the adsorption device (5), a water inlet (4) is provided at one end of the adsorption device (5), a water outlet (10) is provided at one end of the adsorption device (5), a separation recovery-recycling device (6) is installed at the upper end of the adsorption device (5), a servo motor (11) is installed at one end of the separation recovery-recycling device (6), a rotating shaft (13) is provided at the upper end of the servo motor (11), and a square rotating plate (14) is provided at the lower end of the separation recovery-recycling device (6), and the square rotating plate (14) is provided at the lower end of the separation recovery-recycling device (6). A through circular opening corresponding to the circular hole (16) is provided on the surface of the square rotating plate (14); a plurality of separation and recovery devices (15) corresponding to the through circular opening are installed on the upper surface of the square rotating plate (14); a semicircular hole is provided at one end of the square rotating plate (14); one side of the semicircular hole is welded to the outer surface of the rotating shaft (13); a triangular bracket (12) corresponding to the rotating shaft (13) is provided on one side of the square rotating plate (14); the triangular bracket (12) is connected to the rotating shaft (13); a regeneration device (7) is provided on the upper surface of the base (3); a filtering device (8) is provided at one end of the regeneration device (7); and a sedimentation collection box (9) is provided at one end of the upper surface of the base (3).

2. A high-precision treatment and resource utilization system for fluorine-containing wastewater according to claim 1, characterized in that: The adsorption device (5) is provided with a cylindrical adsorption pool inside, a baffle (23) is provided inside the adsorption pool, a primary adsorption pool (24) and a secondary adsorption pool (25) are provided on both sides of the adsorption pool, the baffle (23) is provided in the middle of the primary adsorption pool (24) and the secondary adsorption pool (25), and two stirring devices (26) are installed inside the primary adsorption pool (24) and the secondary adsorption pool (25).

3. A high-precision treatment and resource utilization system for fluorine-containing wastewater according to claim 2, characterized in that: A motor a (29) is installed at one end of the stirring device (26), a rotating rod (30) is arranged at one end of the motor a (29), stirring rods (33) are arranged on both sides of one end of the rotating rod (30), three stirring blades a (34) are arranged on the outer surface of the stirring rod (33), and the inclination angle between the stirring blades a (34) is set to 120 degrees, a driving gear (31) is arranged on the outer surface of the rotating rod (30), and a driven gear (32) corresponding to the driving gear (31) is arranged on the outer surface of one side of the stirring rod (33), and the driving gear (31) is meshed with the driven gear (32), and three stirring blades b (35) are arranged on the outer surface of the bottom end of the rotating rod (30).

4. A high-precision treatment and resource utilization system for fluorine-containing wastewater according to claim 3, characterized in that: The regeneration device (7) is provided with a cylindrical regeneration tank of the same shape as the adsorption device (5), the top of the regeneration device (7) is provided with eight circular holes (16), the inner wall of the upper end of the regeneration device (7) is provided with the stirring device (26), the regeneration device (7) is provided with a flushing device (27), the flushing device (27) is provided with four pointed nozzles, the pointed nozzles are provided at the lower ends of the circular holes (16), and the nozzles are 60 degrees toward the circular holes (16), and the dosing device a (17) and the dosing device b (18) are respectively provided on both sides of the upper end of the regeneration device (7).

5. A high-precision treatment and resource utilization system for fluorine-containing wastewater according to claim 4, characterized in that: A disc (38) is arranged inside the separation and recovery device (15), a motor b (39) is installed on one side of the upper surface of the disc (38), a barrel wheel (40) is arranged on the upper end of the motor b (39), an arc-shaped slide groove (41) is provided on the outer surface of the barrel wheel (40), a columnar slider (43) is slidably connected inside the arc-shaped slide groove (41), a box body (42) corresponding to the motor b (39) is arranged on one side of the upper surface of the disc (38), a right groove (44) is arranged on one side of the surface of the box body (42), the columnar slider (43) is slidably connected inside the right groove (44), the circular hole (16) is arranged in the middle of the disc (38), a hollow cylindrical bottom tube (36) corresponding to the circular hole (16) is arranged on the lower surface of the disc (38), and hydraulic rods (37) are installed on four sides of the lower surface of the disc (38).

6. A high-precision treatment and resource utilization system for fluorine-containing wastewater according to claim 5, characterized in that: A spring (45) is installed inside the box (42), a magnet (46) is arranged inside the spring (45), a round pressing block (47) is arranged at the upper end of the magnet (46), rectangular sliders (48) are arranged on both sides of the round pressing block (47), the columnar slider (43) is arranged on the surface of one side of the rectangular slider (48), and a left groove (49) corresponding to the rectangular slider (48) is opened on the other side surface of the box (42).

7. A high-precision treatment and resource utilization system for fluorine-containing wastewater according to claim 6, characterized in that: The magnet (46) is made of neodymium iron boron magnet.

8. A high-precision treatment and resource utilization system for fluorine-containing wastewater according to claim 7, characterized in that: A sedimentation bin (50) is provided at the lower end of the filter device (8), a filtrate bin (51) is provided at the upper end of the filter device (8), a filter screen (28) is provided between the sedimentation bin (50) and the filtrate bin (51), a sludge suction pipe (19) is provided at one end of the filter device (8), the sludge suction pipe (19) is connected to the regeneration device (7), a sedimentation discharge pipe (22) is provided at one end of the filter device (8), the sedimentation discharge pipe (22) is connected to the sedimentation collection box (9), a return pipe (21) is provided at the upper end of the filter device (8), the other end of the return pipe (21) is connected to the regeneration device (7), and a pump (20) is installed at one end of the return pipe (21), the sludge suction pipe (19) and the sedimentation discharge pipe (22), respectively.

9. A high-precision treatment and resource utilization system for fluorine-containing wastewater according to claim 8, characterized in that: The PLC automatic control system (2) is provided with fluorine ion sensors at the water inlet (4), the water outlet (10) and the regeneration device (7) of the adsorption device (5), respectively, and a conductivity sensor is provided in the regeneration device (7).

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