Device for recovering surfactant from PTFE (Polytetrafluoroethylene) washing wastewater

Abstract

The utility model discloses a device for recovering a surfactant from PTFE (Polytetrafluoroethylene) washing wastewater, and relates to the technical field of production wastewater recovery. The system comprises a recovery adjusting device, the recovery adjusting device is connected with a precipitation device, the precipitation device is connected with a sludge dewatering device, the precipitation device is connected with a multi-medium filtration ultrafiltration device, the multi-medium filtration ultrafiltration device is connected with a first-stage reverse osmosis device, the first-stage reverse osmosis device is connected with a second-stage reverse osmosis device, and the second-stage reverse osmosis device is connected with a third-stage reverse osmosis device. The second-stage reverse osmosis equipment is connected with third-stage reverse osmosis equipment, and the third-stage reverse osmosis equipment is connected with distillation equipment. According to the utility model, a set of device for recovering condensed discharged water generated in the PTFE production process is designed, so that the load of a downstream sewage treatment station is prevented from being increased, the repeated utilization rate of water and materials is improved, wastes are converted into raw materials, and a surfactant in wastewater is separated, concentrated and reused in the chemical production process; and the purified water is recycled to be supplied to the circulating water station.

Description

Technical Field

[0001] The utility model belongs to the technical field of production waste water recovery, and in particular relates to a device for recovering a surfactant from PTFE washing waste water. Background Art

[0002] Polytetrafluoroethylene (PTFE for short) is a high molecular polymer made by polymerizing tetrafluoroethylene as a monomer. It has excellent heat and cold resistance, acid and alkali resistance, resistance to various organic solvents, and is almost insoluble in all solvents. PTFE can be used in corrosion-resistant pipes, containers, pumps, valves, radars, high-frequency communication equipment, radio equipment, etc. with high performance requirements. It is a very important plastic category. In the PTFE production process, surfactants are needed to wash the PTFE resin particles after the polymerization reaction is completed to remove impurities such as catalysts and solvents to obtain pure PTFE resin particles. Therefore, a certain amount of surfactant waste liquid and other pollutants are contained in the condensation drainage.

[0003] Usually, production units will pre-treat this part of wastewater and discharge it into the factory sewage treatment station for treatment after reaching the third level standard of the "Pollutant Discharge Standard for Urban Sewage Treatment Plants" instead of recycling it. This will lead to a series of problems such as low overall water reuse rate in the factory, high surfactant consumption, and high impact on downstream sewage treatment stations.

[0004] Currently, no effective solution has been proposed for the problems in the related technologies. Utility Model Content

[0005] In view of the problems in the related art, the utility model proposes a device for recovering surfactant from PTFE washing wastewater to overcome the above technical problems existing in the existing related art.

[0006] In order to solve the above technical problems, the utility model is realized by the following technical solutions:

[0007] The utility model discloses a device for recovering surfactant from PTFE washing wastewater, comprising a recovery and regulation device, wherein the recovery and regulation device is connected with a precipitation device, wherein the precipitation device is connected with a sludge dewatering device, wherein the precipitation device is connected with a multi-media filtration ultrafiltration device, wherein the multi-media filtration ultrafiltration device is connected with a primary reverse osmosis device, wherein the primary reverse osmosis device is connected with a secondary reverse osmosis device, wherein the secondary reverse osmosis device is connected with a tertiary reverse osmosis device, and wherein the tertiary reverse osmosis device is connected with a distillation device.

[0008] Furthermore, the recovery and adjustment equipment includes coagulation drainage generated during the PTFE production process, the coagulation drainage generated during the PTFE production process is connected to a regulating water tank, the regulating water tank is connected to a regulating water pump, the coagulation equipment includes coagulation and sedimentation equipment, the coagulation and sedimentation equipment is connected to PAC dosing, and the coagulation and sedimentation equipment is connected to anionic PAM dosing.

[0009] Furthermore, the sludge dewatering equipment includes a sludge storage tank, the sludge storage tank is connected to mud, the sludge storage tank is connected to a sludge feed pump, the sludge feed pump is connected to a cationic PAM dosing device, the cationic PAM dosing device is connected to a sludge dewatering machine, the sludge dewatering machine is connected to a mud cake, and the mud cake is connected to a filtrate press.

[0010] Furthermore, the multi-media filtration ultrafiltration equipment includes a clean water tank, the clean water tank is connected to a filtration water pump, the filtration water pump is connected to a bactericide dosing agent, the filtration water pump is connected to a multi-media filter, the multi-media filter is connected to an ultrafiltration equipment, the ultrafiltration equipment is connected to an ultrafiltration water tank, the ultrafiltration water tank is connected to an ultrafiltration backwash pump, the ultrafiltration backwash pump is connected to a multi-media backwash pump, the ultrafiltration equipment is connected to ultrafiltration backwash sewage, and the multi-media filter is connected to multi-media backwash sewage.

[0011] Furthermore, the first-level reverse osmosis equipment includes a first-level water supply pump, the first-level water supply pump is respectively connected to the scale inhibitor dosing and the reducing agent dosing, the first-level water supply pump is connected to the first-level safety filter, the first-level safety filter is connected to the first-level high-pressure pump, the first-level high-pressure pump is connected to the first-level RO equipment, the first-level RO equipment is respectively connected to the first-level RO produced water and the first-level RO concentrated water, the first-level RO produced water is connected to the recycled water, and the first-level RO concentrated water is connected to the first-level concentrated water tank.

[0012] Furthermore, the secondary reverse osmosis equipment includes a secondary water supply pump, the secondary water supply pump is connected to a secondary safety filter, the secondary safety filter is connected to a secondary high-pressure pump, the secondary high-pressure pump is connected to a secondary DTRO equipment, the secondary DTRO equipment is respectively connected to secondary DTRO produced water and secondary DTRO concentrated water, and the secondary DTRO concentrated water is connected to a secondary concentrated water tank.

[0013] Furthermore, the three-stage reverse osmosis equipment includes a three-stage water supply pump, the three-stage water supply pump is connected to a three-stage security filter, the three-stage security filter is connected to a three-stage high-pressure pump, the three-stage high-pressure pump is connected to a three-stage DTRO equipment, and the three-stage DTRO equipment is respectively connected to three-stage DTRO produced water and three-stage DTRO concentrated water.

[0014] Furthermore, the distillation equipment includes a raw material tank, the raw material tank is connected to a raw material pump, the raw material pump is connected to a distillation equipment, and the distillation equipment is respectively connected to a steam condensate and a surfactant concentrate.

[0015] The utility model has the following beneficial effects:

[0016] 1. The utility model designs a device for recovering condensed water generated in the PTFE production process. In order to avoid increasing the load of the downstream sewage treatment station and improve the reuse rate of water and materials, the waste is converted into raw materials, the surfactant in the wastewater is separated and concentrated, and reused in the chemical production process, and the purified water is reused to supply the circulating water station, the surfactant in the wastewater is recovered and reused in the production process, thereby reducing production costs.

[0017] 2. The utility model purifies the wastewater and reuses it to supply the circulating water station, thereby improving the overall water utilization rate of the device.

[0018] 3. The utility model prevents wastewater discharge from occupying the operating capacity of the downstream sewage treatment plant.

[0019] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the utility model embodiments, the drawings required for describing the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 It is a schematic diagram of the process flow diagram structure of the utility model;

[0022] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0023] 1. Coagulation drainage generated during PTFE production; 2. Regulating water tank; 3. Regulating water pump; 4. Coagulation and sedimentation equipment; 5. PAC dosing; 6. Anionic PAM dosing; 7. Mud; 8. Sludge storage tank; 9. Sludge feed pump; 10. Cationic PAM dosing; 11. Sludge dewatering machine; 12. Mud cake; 13. Filtrate press; 14. Clean water tank; 15. Filter water pump; 16. Bactericide dosing; 17. Multi-media filter; 18. Ultrafiltration equipment; 19. Ultrafiltration water tank; 20. Ultrafiltration backwash pump; 21. Multi-media backwash pump; 22. Ultrafiltration backwash sewage; 23. Multi-media backwash sewage; 24. Primary water pump; 25. Antiscalant dosing; 26. Reductant dosing; 27. Primary Security filter; 28. First-stage high-pressure pump; 29. ​​First-stage RO equipment; 30. First-stage RO produced water; 31. First-stage RO concentrated water; 32. First-stage concentrated water tank; 33. Second-stage water supply pump; 34. Second-stage security filter; 35. Second-stage high-pressure pump; 36. Second-stage DTRO equipment; 37. Second-stage DTRO produced water; 38. Second-stage DTRO concentrated water; 39. Second-stage concentrated water tank; 40. Third-stage water supply pump; 41. Third-stage security filter; 42. Third-stage high-pressure pump; 43. Third-stage DTRO equipment; 44. Third-stage DTRO produced water; 45. Third-stage DTRO concentrated water; 46. Raw material tank; 47. Raw material pump; 48. Distillation equipment; 49. Steam condensate; 50. Recycled water; 51. Surfactant concentrate. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the utility model embodiments to clearly and completely describe the technical solutions in the utility model embodiments. Obviously, the described embodiments are only part of the utility model embodiments, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0025] In the description of the present utility model, it should be understood that the terms "opening", "upper", "lower", "top", "middle", "inside" and the like indicating orientation or positional relationship are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the components or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model.

[0026] See also Figure 1As shown, the utility model is a device for recovering surfactants from PTFE washing wastewater, including a recovery and regulation device, the recovery and regulation device is connected to a precipitation device, the precipitation device is connected to a sludge dewatering device, the precipitation device is connected to a multi-media filtration ultrafiltration device, the multi-media filtration ultrafiltration device is connected to a primary reverse osmosis device, the primary reverse osmosis device is connected to a secondary reverse osmosis device, the secondary reverse osmosis device is connected to a tertiary reverse osmosis device, and the tertiary reverse osmosis device is connected to a distillation device.

[0027] The condensation drainage generated in the PTFE production process is collected and processed, wherein the recovery and regulation equipment is used to homogenize and equalize the intermittently discharged condensation drainage so that the reuse equipment can operate continuously and stably. The coagulation and sedimentation equipment is used to remove SS paraffin, PTFE particles, etc. in the drainage, and the produced water SS is ≤10mg / L. The multi-media filtration ultrafiltration equipment is used to deeply remove turbidity from the drainage to avoid clogging of the subsequent reverse osmosis membrane, and the produced water turbidity is ≤0.1NTU. The first-level reverse osmosis equipment adopts a spiral reverse osmosis membrane with a recovery rate of 75%, and the surfactant is concentrated for the first time. The second-level reverse osmosis equipment adopts a disc-type reverse osmosis membrane column with a recovery rate of 75%, and the surfactant is concentrated for the second time. The third-level reverse osmosis equipment adopts a disc-type reverse osmosis membrane column with a recovery rate of 60%, and the surfactant is concentrated for the third time. After the third-level membrane equipment, the surfactant concentration is concentrated to 40 times. The distillation equipment adopts a forced circulation evaporator, and finally the surfactant is concentrated to 800 times, and the concentration reaches more than 20%, which is repeatedly used in the washing process of producing PTFE. The sludge dewatering equipment is used to produce the concentrated sludge in the coagulation and sedimentation tank in a solid form.

[0028] The utility model designs a device for recycling condensed water generated in the PTFE production process. In order to avoid increasing the load of the downstream sewage treatment station and improve the reuse rate of water and materials, the waste is converted into raw materials, the surfactant in the wastewater is separated and concentrated, and reused in the chemical production process, and the purified water is reused to supply the circulating water station.

[0029] In one embodiment, for the above-mentioned recovery and adjustment equipment, the recovery and adjustment equipment includes a coagulation wastewater 1 generated in the PTFE production process, the coagulation wastewater 1 generated in the PTFE production process is connected to a regulating water tank 2, the regulating water tank is connected to a regulating water pump 3, the coagulation equipment includes a coagulation sedimentation equipment 4, the coagulation sedimentation equipment 4 is connected to a PAC dosing 5, and the coagulation sedimentation equipment 4 is connected to an anionic PAM dosing 6.

[0030] The condensed wastewater 1 generated during the PTFE production process is intermittently discharged into the regulating tank 2, and after being homogenized and equalized, it is pressurized by the regulating water pump 3 and sent to the coagulation sedimentation tank 4. Through the PAC dosing 5 and the anionic PAM dosing 6, it chemically reacts with the suspended matter and colloid in the wastewater to form large alum flowers, which are then precipitated and separated in the reactor.

[0031] In one embodiment, for the above-mentioned sludge dewatering equipment, the sludge dewatering equipment includes a sludge storage tank 8, the sludge storage tank 8 is connected to the sludge 7, the sludge storage tank 8 is connected to the sludge feed pump 9, the sludge feed pump 9 is connected to the cationic PAM dosing 10, the cationic PAM dosing 10 is connected to the sludge dewatering machine 11, the sludge dewatering machine 11 is connected to the mud cake 12, and the mud cake 12 is connected to the filtrate press 13.

[0032] The sludge 7 generated during the coagulation reaction flows by gravity into the sludge storage tank 8, is pressurized by the sludge feed pump 9, mixed with the cationic PAM dosing 10, and then enters the sludge dewatering machine 11 for solid-liquid separation. The produced solid mud cake 12 is processed externally, and the filtrate 13 is returned to the regulating tank 2 for secondary treatment.

[0033] In one embodiment, for the above-mentioned multi-media filtration ultrafiltration equipment, the multi-media filtration ultrafiltration equipment includes a clean water tank 14, the clean water tank 14 is connected to a filtration water pump 15, the filtration water pump 15 is connected to a bactericide dosing 16, the filtration water pump 15 is connected to a multi-media filter 17, the multi-media filter 17 is connected to an ultrafiltration equipment 18, the ultrafiltration equipment 18 is connected to an ultrafiltration water tank 19, the ultrafiltration water tank 19 is connected to an ultrafiltration backwash pump 20, the ultrafiltration backwash pump 20 is connected to a multi-media backwash pump 21, the ultrafiltration equipment 18 is connected to an ultrafiltration backwash wastewater 22, and the multi-media filter 17 is connected to a multi-media backwash wastewater 23.

[0034] Through PAC dosing 5 and anionic PAM dosing 6, chemical reactions occur with suspended matter and colloids in the wastewater to form large alum flowers, and then the supernatant clarified water effluent after precipitation and separation is discharged to the clean water tank 14. The clean water in the clean water tank 14 is pressurized by the filter water pump 15, and after being mixed with the bactericide dosing 16, it passes through the multi-media filter 17 and the ultrafiltration equipment 18 in sequence. The ultrafiltration produced water enters the ultrafiltration water tank 19. An ultrafiltration backwash pump 20 and a multi-media backwash pump 21 are respectively arranged behind the ultrafiltration water tank 19 as the backwash water for the multi-media filter 17 and the ultrafiltration equipment 18. The ultrafiltration backwash wastewater 22 and the multi-media backwash wastewater 23 are returned to the regulating tank 2 for secondary treatment.

[0035] In one embodiment, for the above-mentioned first-level reverse osmosis equipment, the first-level reverse osmosis equipment includes a first-level water supply pump 24, the first-level water supply pump 24 is respectively connected to the scale inhibitor dosing 25 and the reducing agent dosing 26, the first-level water supply pump 24 is connected to the first-level safety filter 27, the first-level safety filter 27 is connected to the first-level high-pressure pump 28, the first-level high-pressure pump 28 is connected to the first-level RO equipment 29, the first-level RO equipment 29 is respectively connected to the first-level RO produced water 30 and the first-level RO concentrated water 31, the first-level RO produced water is connected to the recycled water 50, and the first-level RO concentrated water 31 is connected to the first-level concentrated water tank 32.

[0036] The ultrafiltration water is pressurized by the primary water pump 24, mixed with the scale inhibitor 25 and the reducing agent 26, and then enters the primary security filter 27, the primary high-pressure pump 28 and the primary RO equipment 29 connected in series one by one for the first concentration, with a concentration ratio of 4 times and a water recovery rate of 75%. The primary RO water 30 is used as recycled water 50 and can be used to replenish circulating water. The primary RO concentrated water 31 enters the primary concentrated water tank 32 for buffering.

[0037] In one embodiment, for the above-mentioned secondary reverse osmosis equipment, the secondary reverse osmosis equipment includes a secondary water supply pump 33, the secondary water supply pump 33 is connected to a secondary safety filter 34, the secondary safety filter 34 is connected to a secondary high-pressure pump 35, the secondary high-pressure pump 35 is connected to a secondary DTRO equipment 36, the secondary DTRO equipment 36 is respectively connected to a secondary DTRO produced water 37 and a secondary DTRO concentrated water 38, and the secondary DTRO concentrated water 38 is connected to a secondary concentrated water tank 39.

[0038] After the primary RO concentrated water 31 enters the primary concentrated water tank 32 for buffering, it is pressurized by the secondary water supply pump 33, mixed with the scale inhibitor 25, and then enters the secondary security filter 34, the secondary high-pressure pump 35 and the secondary DTRO equipment 36 connected in series one by one for the second concentration, with a concentration ratio of 4 times and a water recovery rate of 75%. The secondary DTRO produced water 37 is used as recycled water 50 and can be used to replenish circulating water.

[0039] In one embodiment, for the above-mentioned three-stage reverse osmosis equipment, the three-stage reverse osmosis equipment includes a three-stage water supply pump 40, the three-stage water supply pump 40 is connected to a three-stage security filter 41, the three-stage security filter 41 is connected to a three-stage high-pressure pump 42, the three-stage high-pressure pump 42 is connected to a three-stage DTRO equipment 43, and the three-stage DTRO equipment 43 is respectively connected to a three-stage DTRO produced water 44 and a three-stage DTRO concentrated water 45.

[0040] The secondary DTRO concentrated water 38 enters the secondary concentrated water tank 39 for buffering, is pressurized by the tertiary water pump 40, and is mixed with the scale inhibitor 25 before entering the one-to-one series-connected tertiary security filter 41, tertiary high-pressure pump 42, and tertiary DTRO equipment 43 for the third concentration, with a concentration ratio of 2.5 times and a water recovery rate of 60%. Affected by the desalination rate of the reverse osmosis membrane, the surfactant concentration in the tertiary DTRO produced water 44 is similar to that of the influent water, and is returned to the ultrafiltration water tank 19 for secondary treatment.

[0041] In one embodiment, for the above-mentioned distillation equipment, the distillation equipment includes a raw material tank 46, the raw material tank 46 is connected to a raw material pump 47, the raw material pump 47 is connected to a distillation device 48, and the distillation device 48 is respectively connected to a steam condensate 49 and a surfactant concentrate 51.

[0042] The tertiary DTRO concentrated water 45 enters the raw material tank 46 for buffering, and is pressurized by the raw material pump 47 to the distillation equipment 48 for final concentration. The concentration ratio is 20 times and the water recovery rate is 95%. The steam condensate 49 generated during the distillation process is used as recycled water 50 and can be used to replenish circulating water. The final surfactant concentrated solution 51 has a concentration greater than 20% and is reused in the production process of PTFE.

[0043] Through the above technical scheme, 1. By designing a set of equipment to recycle the condensed water generated in the PTFE production process, in order to avoid increasing the load of the downstream sewage treatment plant and improve the reuse rate of water and materials, the waste is converted into raw materials, the surfactant in the wastewater is separated and concentrated, and reused in the chemical production process, and the purified water is reused in the replenishment circulating water station, the surfactant in the wastewater is recovered and reused in the production process, and the production cost is reduced; 2. The purified wastewater is reused in the replenishment circulating water station to improve the overall water utilization rate of the device; 3. Avoid wastewater discharge occupying the operating capacity of the downstream sewage treatment plant.

[0044] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0045] The preferred embodiments of the utility model disclosed above are only used to help explain the utility model. The preferred embodiments do not describe all the details in detail, nor do they limit the utility model to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the utility model, so that technicians in the relevant technical field can well understand and use the utility model. The utility model is limited only by the claims and their full scope and equivalents.

Claims

1. A device for recovering surfactant from PTFE washing wastewater, comprising a recovery and conditioning device, characterized in that: The recovery and regulation equipment is connected to a sedimentation equipment, the sedimentation equipment is connected to a sludge dewatering equipment, the sedimentation equipment is connected to a multi-media filtration ultrafiltration equipment, the multi-media filtration ultrafiltration equipment is connected to a first-stage reverse osmosis equipment, the first-stage reverse osmosis equipment is connected to a second-stage reverse osmosis equipment, the second-stage reverse osmosis equipment is connected to a third-stage reverse osmosis equipment, and the third-stage reverse osmosis equipment is connected to a distillation equipment.

2. A device for recovering surfactant from PTFE washing wastewater according to claim 1, characterized in that: The recovery and adjustment equipment comprises coagulation drainage (1) generated in the PTFE production process, the coagulation drainage (1) generated in the PTFE production process is connected to a regulating water tank (2), the regulating water tank is connected to a regulating water pump (3), the coagulation equipment comprises coagulation sedimentation equipment (4), the coagulation sedimentation equipment (4) is connected to a PAC dosing device (5), and the coagulation sedimentation equipment (4) is connected to an anionic PAM dosing device (6).

3. A device for recovering surfactant from PTFE washing wastewater according to claim 1, characterized in that: The sludge dewatering equipment comprises a sludge storage tank (8), the sludge storage tank (8) is connected to sludge (7), the sludge storage tank (8) is connected to a sludge feed pump (9), the sludge feed pump (9) is connected to a cationic PAM dosing device (10), the cationic PAM dosing device (10) is connected to a sludge dewatering machine (11), the sludge dewatering machine (11) is connected to a sludge cake (12), and the sludge cake (12) is connected to a filtrate press (13).

4. A device for recovering surfactant from PTFE washing wastewater according to claim 1, characterized in that: The multi-media filtration ultrafiltration equipment comprises a clean water tank (14), the clean water tank (14) is connected to a filtration water supply pump (15), the filtration water supply pump (15) is connected to a bactericide dosing device (16), the filtration water supply pump (15) is connected to a multi-media filter (17), the multi-media filter (17) is connected to an ultrafiltration device (18), the ultrafiltration device (18) is connected to an ultrafiltration water tank (19), the ultrafiltration water tank (19) is connected to an ultrafiltration backwash pump (20), the ultrafiltration backwash pump (20) is connected to a multi-media backwash pump (21), the ultrafiltration device (18) is connected to ultrafiltration backwash wastewater (22), and the multi-media filter (17) is connected to multi-media backwash wastewater (23).

5. A device for recovering surfactant from PTFE washing wastewater according to claim 1, characterized in that: The primary reverse osmosis equipment comprises a primary water supply pump (24), the primary water supply pump (24) is respectively connected to a scale inhibitor dosing device (25) and a reducing agent dosing device (26), the primary water supply pump (24) is connected to a primary safety filter (27), the primary safety filter (27) is connected to a primary high-pressure pump (28), the primary high-pressure pump (28) is connected to a primary RO device (29), the primary RO device (29) is respectively connected to a primary RO produced water (30) and a primary RO concentrated water (31), the primary RO produced water is connected to recycled water (50), and the primary RO concentrated water (31) is connected to a primary concentrated water tank (32).

6. A device for recovering surfactant from PTFE washing wastewater according to claim 1, characterized in that: The secondary reverse osmosis equipment comprises a secondary water supply pump (33), the secondary water supply pump (33) is connected to a secondary security filter (34), the secondary security filter (34) is connected to a secondary high-pressure pump (35), the secondary high-pressure pump (35) is connected to a secondary DTRO equipment (36), the secondary DTRO equipment (36) is respectively connected to secondary DTRO produced water (37) and secondary DTRO concentrated water (38), and the secondary DTRO concentrated water (38) is connected to a secondary concentrated water tank (39).

7. A device for recovering surfactant from PTFE washing wastewater according to claim 1, characterized in that: The three-stage reverse osmosis equipment comprises a three-stage water supply pump (40), the three-stage water supply pump (40) is connected to a three-stage security filter (41), the three-stage security filter (41) is connected to a three-stage high-pressure pump (42), the three-stage high-pressure pump (42) is connected to a three-stage DTRO equipment (43), and the three-stage DTRO equipment (43) is respectively connected to three-stage DTRO produced water (44) and three-stage DTRO concentrated water (45).

8. A device for recovering surfactant from PTFE washing wastewater according to claim 1, characterized in that: The distillation equipment comprises a raw material tank (46), the raw material tank (46) is connected to a raw material pump (47), the raw material pump (47) is connected to a distillation equipment (48), and the distillation equipment (48) is respectively connected to a steam condensate (49) and a surfactant concentrate (51).

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