An automobile painting plant water-soluble solvent paint waste liquid recycling device

Abstract

The application discloses a kind of automobile painting workshop water-soluble solvent paint waste liquid recovery processing device, it is related to sewage treatment technical field, including the pre-filtering mechanism, ultrafiltration system, nanofiltration system and reverse osmosis system being arranged in series successively, wherein, pre-filtering mechanism includes jar body, the inside of jar body is provided with filter cartridge one, the bottom of jar body is fixed with liquid outlet pipe, further including equalizing filter assembly, equalizing filter assembly includes the filter cartridge two and stirring rod being set to the inside of jar body, the present application is matched with the change of waste liquid viscosity by flux adjusting structure, the effective filtration area of pre-filtering mechanism, under the condition of high viscosity of waste liquid, filtration area expands to compensate flux attenuation, under the condition of low viscosity, filtration area is narrowed to limit filtration speed, so that the liquid flow of pre-filtering mechanism is maintained in stable interval, ultrafiltration system, nanofiltration system and reverse osmosis system are stabilized in optimal operating condition, improve the wastewater treatment efficiency and effect of entire device.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, and in particular to a device for recycling and treating water-soluble solvent paint waste liquid in automotive painting workshops. Background Technology

[0002] Water-soluble solvent paint is a new type of environmentally friendly coating that uses water as a diluent or dispersion medium. Its main components include water-based resin, pigments and fillers, alcohol ether cosolvents, deionized water, and various functional additives. It is now widely used in the body intermediate coating, topcoat, and clear coat spraying processes of automotive painting production lines.

[0003] In the automotive painting process, processes such as spray booths, paint mixing rooms, and cleaning of spraying equipment generate a large amount of water-soluble solvent paint waste liquid. This waste liquid not only contains unused water-based resins, pigments, and fillers, but also a certain amount of alcohol ether co-solvents, pH adjusters, and surfactants. If discharged directly without treatment, it will cause continuous pollution to water bodies and soil. Therefore, recycling and treating this type of waste liquid is a key technical means to reduce enterprises' hazardous waste disposal costs and achieve cleaner production in the workshop.

[0004] Existing water-soluble solvent paint wastewater recovery and treatment devices mainly consist of a pre-filtration unit, an ultrafiltration system, a nanofiltration system, and a reverse osmosis system connected in series. These multi-stage membrane separation processes recover paint, pure water, and water-soluble co-solvents from the wastewater. However, the concentration of paint wastewater discharged from different processes and at different times in automotive painting workshops varies significantly. When the wastewater from each branch converges into the pre-filtration unit, the concentration fluctuates continuously. Since water-soluble paint wastewater itself has a certain viscosity, these concentration fluctuations directly lead to dynamic changes in the viscosity of the wastewater, resulting in unstable permeate flux in the pre-filtration unit and inconsistent effluent flow rates. This causes continuous fluctuations in the influent load of the subsequent ultrafiltration, nanofiltration, and reverse osmosis treatment systems, preventing them from operating stably under optimal conditions. Consequently, the overall treatment efficiency and effectiveness of the system are constrained. Summary of the Invention

[0005] The purpose of this invention is to solve the problem that the pre-filtration mechanism in existing water-soluble solvent paint waste liquid recycling and treatment devices experiences fluctuating flow rates due to dynamic changes in waste liquid concentration, which prevents subsequent ultrafiltration, nanofiltration, and reverse osmosis treatment systems from operating stably under optimal conditions. Therefore, this invention proposes a water-soluble solvent paint waste liquid recycling and treatment device for automotive painting workshops.

[0006] To achieve the above objectives, the present invention employs the following technology: a water-soluble solvent paint waste liquid recovery and treatment device for automotive painting workshops, comprising a pre-filtration mechanism, an ultrafiltration system, a nanofiltration system, and a reverse osmosis system arranged in series, wherein the pre-filtration mechanism includes a tank, a filter cartridge is disposed inside the tank, and an outlet pipe is fixed at the bottom of the tank, and further includes: A balanced filtration assembly includes a filter cylinder 2 and a stirring rod disposed inside the tank body. The filter cylinder 1 consists of an upper connecting section and a lower filtration section. The filter cylinder 2 is sleeved outside the upper connecting section. A main shaft is rotatably connected inside the tank body, and a flow rate adjustment structure is disposed on the main shaft. A drive assembly, the drive assembly including a motor fixedly mounted on the top of the tank; The flow rate adjustment structure adjusts the height of filter cartridge two by the rotational resistance of the stirring rod, so that the effective filtration area of ​​filter cartridge two matches the viscosity of paint waste liquid, and stabilizes the discharge flow rate of the pre-filtration mechanism.

[0007] As a further description of the above-mentioned technology of a water-soluble solvent paint waste liquid recycling and treatment device in an automotive painting workshop: the throughput adjustment structure includes a sleeve sleeved outside the main shaft and fixed to the filter cartridge two; a slider embedded in the spiral groove of the inner wall of the sleeve is fixed on the outer wall of the main shaft; and a spring is provided between the inner wall of the sleeve and the outer wall of the main shaft.

[0008] As a further description of the above-mentioned technology of a water-soluble solvent paint waste liquid recycling and treatment device in an automotive painting workshop: a transmission unit one and a transmission unit two are connected between the motor and the main shaft. The transmission unit one includes a positioning plate rotatably connected to the top of the tank and fixed to the motor drive shaft. A turntable is slidably connected to the top of the main shaft. A push column is eccentrically fixed to the top surface of the positioning plate.

[0009] As a further description of the above-mentioned technology of a water-soluble solvent paint waste liquid recycling and treatment device in an automotive painting workshop: the transmission unit two includes a gear one fixed to the bottom of the positioning plate, and a gear two is slidably connected to the top end of the main shaft.

[0010] As a further description of the above-mentioned automotive painting workshop water-soluble solvent paint waste liquid recycling and treatment device: a connecting pipe is fixed between the turntable and the second gear, and the connecting pipe is sleeved on the top of the main shaft and fixed to the main shaft by bolts.

[0011] As a further description of the above-mentioned technology of a water-soluble solvent paint waste liquid recycling and treatment device in an automotive painting workshop: a resistance adjustment unit is provided on the sleeve, the resistance adjustment unit includes a connecting frame slidably connected to the outside of the sleeve, an adapter seat fixed to the stirring rod is rotatably connected to the outside of the sleeve, and a connecting rod is hinged between the connecting frame and the adapter seat.

[0012] As a further description of the above-mentioned technology of a water-soluble solvent paint waste liquid recycling and treatment device in an automotive painting workshop: the top of the sleeve is threadedly connected to a threaded sleeve that is rotatably connected to the connecting frame, and a plurality of the adapter seats are arranged in a row, with a connecting rod two hinged between two adjacent adapter seats in each row.

[0013] As a further description of the above-mentioned technology of a water-soluble solvent paint waste liquid recycling and treatment device in an automotive painting workshop: it also includes an auxiliary cleaning structure, the auxiliary cleaning structure including a docking plate one fixed to the bottom end of the sleeve and a docking plate two fixed to the inner wall of the filter cylinder one, and fitting blocks fixed on opposite sides of the docking plate one and the docking plate two, and the bottom of the filter cylinder one is rotatably connected to a mounting base fixed to the tank body.

[0014] As a further description of the above-mentioned device for recycling and treating water-soluble solvent paint waste liquid in an automotive painting workshop: a drain pipe is fixed at the bottom of the tank, and valves are installed on both the liquid outlet pipe and the drain pipe.

[0015] As a further description of the above-mentioned technology of a water-soluble solvent paint waste liquid recycling and treatment device in an automotive painting workshop: the bottom of the filter cylinder two is fixed with a scraper that contacts the outer wall of the filter cylinder one.

[0016] In summary, due to the adoption of the above-mentioned technology in the automotive painting workshop water-soluble solvent paint waste liquid recycling and treatment device, the beneficial effects of this invention are: 1. This invention uses a flux adjustment structure to match the effective filtration area of ​​the pre-filtration mechanism with the viscosity of the waste liquid. Under high viscosity conditions, the filtration area expands to compensate for flux attenuation, while under low viscosity conditions, the filtration area narrows to limit the filtration speed. This keeps the effluent flow rate of the pre-filtration mechanism within a stable range, and keeps the ultrafiltration, nanofiltration, and reverse osmosis systems operating at their optimal conditions, thereby improving the wastewater treatment efficiency and effectiveness of the entire device.

[0017] Compared to directly adjusting the discharge speed of the pre-filtration mechanism through the flow regulating valve, this invention automatically increases the filtration area when the waste liquid is viscous, which can reduce the load per unit filter surface, reduce the risk of waste liquid clogging, stabilize the flow rate, and at the same time reduce the pressure on the filter cartridge. When the waste liquid is thin, it automatically reduces the filtration area, increases the local filtration rate, and uses the shear force of the water flow to flush the surface of the filter cartridge, preventing particle clogging and resulting in a stronger wastewater treatment effect.

[0018] 2. In this invention, the stirring rod not only stirs the waste liquid, ensuring its uniform distribution and improving filtration efficiency, but also provides resistance, allowing for adjustment of the filtration area of ​​the pre-filtration mechanism. Furthermore, by adjusting the angle of the stirring rod through the resistance adjustment unit, the effective filtration area of ​​the second filter cartridge in its initial state can be adjusted, facilitating control of the filtration effect based on the actual concentration of the waste liquid and further enhancing its effectiveness.

[0019] 3. During the shutdown cleaning phase, the motor drives the filter cartridge two to perform vertical reciprocating motion through the transmission unit one, the main shaft, and the flow rate adjustment structure. This design not only improves the rinsing effect of water on the filter cartridge two, but also increases the water pressure inside the filter cartridge one and the filter cartridge two during the descent process. This causes water to be squeezed out through the filter holes under pressure, backwashing the impurities in the filter holes, greatly improving the cleaning effect, preventing impurities from clogging the filter holes, and extending the service life of the filter cartridge one and the filter cartridge two.

[0020] 4. The present invention enables the filter cartridge one to rotate at high speed together with the filter cartridge two through the auxiliary cleaning structure. During the shutdown cleaning stage, the impurities on the filter cartridge one and the filter cartridge two are thrown out by centrifugal force, which further improves the cleaning effect of the filter cartridge one and the filter cartridge two and extends their service life. Attached Figure Description

[0021] Figure 1 An overall schematic diagram of the present invention is shown; Figure 2 A schematic diagram of the pre-filtration mechanism of the present invention is shown; Figure 3 A schematic cross-sectional view of the tank body of the present invention is shown; Figure 4 A schematic diagram of the filter cartridge of the present invention is shown; Figure 5 The present invention is shown. Figure 4 Enlarged view of point A in the middle; Figure 6 A schematic diagram of the filter cartridge two of the present invention is shown; Figure 7 A schematic diagram of the flux regulation structure of the present invention is shown; Figure 8 A schematic diagram of the resistance adjustment unit of the present invention is shown; Figure 9 A schematic diagram of the transmission unit of the present invention is shown; Figure 10 A schematic diagram of the transmission unit two of the present invention is shown.

[0022] Legend: 11. Pre-filtration unit; 12. Ultrafiltration system; 13. Nanofiltration system; 14. Reverse osmosis system; 21. Tank body; 22. Filter cartridge one; 23. Discharge pipe; 30. Balanced filtration assembly; 31. Filter cartridge two; 32. Stirring rod; 33. Main shaft; 34. Flow rate adjustment structure; 341. Sleeve; 342. Slider; 343. Spring; 35. Resistance adjustment unit; 351. Connecting frame; 352. Connecting rod one; 353. Adapter seat; 36. Threaded sleeve; 37. Connecting rod two; 40. Drive assembly; 41. Motor; 42. Transmission unit one; 421. Positioning plate; 422. Turntable; 423. Push column; 43. Transmission unit two; 431. Gear one; 432. Gear two; 44. Connecting pipe; 50. Auxiliary cleaning structure; 51. Connecting plate one; 52. Fitting block; 53. Connecting plate two; 54. Mounting base; 55. Drain pipe; 61. Scraper. Detailed Implementation

[0023] The following will describe, with reference to the accompanying drawings of the embodiments of the present invention, a water-soluble solvent paint waste liquid recycling and treatment device for an automotive painting workshop. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] like Figures 1-10 As shown, the present invention provides a water-soluble solvent paint waste liquid recovery and treatment device for automotive painting workshops: including a pre-filtration mechanism 11, an ultrafiltration system 12, a nanofiltration system 13, and a reverse osmosis system 14 arranged in series. After water-soluble solvent paint waste liquid is generated in each process of the automotive painting workshop, the waste liquid is collected in the pre-filtration mechanism 11. The pre-filtration mechanism 11 intercepts impurities such as coagulated paint residue, pigment agglomerates, and large paint flakes in the waste liquid. Water-based resins, nanocolloids, alcohol ether co-solvents, and various small molecule additives in the waste liquid enter the subsequent ultrafiltration system 12, and then pass through the nanofiltration system 13 and the reverse osmosis system 14 in sequence. Through the multi-stage cooperation of each system, the paint, pure water, and water-soluble co-solvents in the waste liquid are recovered.

[0025] The pre-filtration unit 11, ultrafiltration system 12, nanofiltration system 13, and reverse osmosis system 14 have filtration accuracies of 5μm, 1nm-100nm, 0.5nm-1nm, and <0.5nm, respectively. The pre-filtration unit 11 includes a tank 21, inside which is installed a filter cartridge 22 with a filtration accuracy of 5μm. An outlet pipe 23, communicating with the internal space of the filter cartridge 22, is fixed to the bottom of the tank 21, and an inlet is located at the top of the tank 21. Wastewater flows into the tank 21 through the inlet, is filtered by the lower filtration section of the filter cartridge 22, and is then discharged through the outlet pipe 23 to the next-stage wastewater treatment system.

[0026] Reference Figure 3 , Figure 4 and Figure 5To ensure a more stable filtration speed in the pre-filtration mechanism 11, and to guarantee the optimal operation of subsequent wastewater treatment systems at all levels, thus maximizing the overall system's treatment efficiency and effectiveness, a balanced filtration assembly 30 is installed. The balanced filtration assembly 30 includes a second filter cartridge 31 and a stirring rod 32 housed inside the tank 21. The first filter cartridge 22 is tubular, consisting of an upper connecting section and a lower filtration section. The second filter cartridge 31 is fitted onto the outside of the upper connecting section, with its top flush with the top of the first filter cartridge 22 and sealing the top opening of the first filter cartridge 22. Its bottom is sealed to the outer wall of the upper connecting section. The lower filtration section of the first filter cartridge 22 continuously participates in wastewater filtration while maintaining effective filtration. A main shaft 33 is rotatably connected inside the tank 21.

[0027] Reference Figure 6 and Figure 7 The main shaft 33 is provided with a flow rate adjustment structure 34. The flow rate adjustment structure 34 includes a sleeve 341 that is sleeved on the outside of the main shaft 33 and fixed to the filter cartridge 31. The inner wall of the sleeve 341 is provided with a spiral groove. The outer wall of the main shaft 33 is fixed with a slider 342 embedded in the spiral groove. A spring 343 is provided between the inner wall of the sleeve 341 and the outer wall of the main shaft 33. The spring 343 is always in a compressed state. The limiting ring on the outer wall of the main shaft 33 restricts the sleeve 341 from moving downward relative to the main shaft 33. A washer is provided between the bottom end of the spring 343 and the inner wall of the sleeve 341 to prevent the spring 343 from being twisted and damaged when the sleeve 341 rotates relative to the main shaft 33.

[0028] The top of the tank body 21 is provided with a drive assembly 40 for driving the main shaft 33 to rotate. The drive assembly 40 includes a motor 41 fixedly installed on the top of the tank body 21.

[0029] When tank 21 is empty, motor 41 drives main shaft 33 to rotate. Main shaft 33 drives slider 342 to push the inner wall of spiral groove, causing sleeve 341 to rotate, which in turn drives stirring rod 32 arranged outside sleeve 341 to rotate. After wastewater is injected into tank 21, stirring rod 32 will encounter significant resistance during its rotation, hindering the rotation of sleeve 341. Slider 342 will slide inside spiral groove due to the obstruction of the inclined inner wall of spiral groove, causing sleeve 341 to deflect relative to main shaft 33 and move upward, further compressing spring 343. At the same time, sleeve 341 drives filter cartridge 21 to move upward. The portion of filter cartridge 21 that exceeds the top of filter cartridge 22 after moving upward participates in wastewater filtration. Based on the above principle, the height of filter cartridge 21 can increase as the resistance encountered by stirring rod 32 increases during rotation.

[0030] Initially, motor 41 drives main shaft 33 to rotate at a constant speed. Under the resistance of the waste liquid, half of the area of ​​filter cartridge 31 participates in filtration. When the viscosity of the waste liquid increases, the resistance received by stirring rod 32 increases, the height of filter cartridge 31 rises, and the area participating in filtration increases; when the viscosity of the waste liquid decreases, the resistance received by stirring rod 32 decreases, the height of filter cartridge 31 falls, and the effective filtration area decreases. Through the above design, this invention achieves adaptive adjustment of the effective filtration area of ​​pre-filtration mechanism 11 with changes in waste liquid viscosity. Under high viscosity conditions, the filtration area expands to compensate for flux attenuation, and under low viscosity conditions, the filtration area narrows to limit the filtration speed. This keeps the effluent flow rate of pre-filtration mechanism 11 within a stable range, and keeps ultrafiltration system 12, nanofiltration system 13, and reverse osmosis system 14 stable under optimal operating conditions, improving the wastewater treatment efficiency and effect of the entire device.

[0031] Compared to directly adjusting the flow rate of the pre-filtration mechanism 11 to discharge the filtered waste liquid, the present invention, through the above design, can automatically increase the filtration area when the waste liquid is viscous, reduce the unit filter surface load, reduce the risk of waste liquid clogging, stabilize the flow rate, and at the same time reduce the pressure on the filter cartridge 22; when the waste liquid is thin, it automatically reduces the filtration area, increases the local filtration rate, and uses the shear force of the water flow to flush the surface of the filter cartridge 22, prevents particle clogging, and extends the service life of the filter cartridge 22.

[0032] Reference Figure 7 and Figure 8 In order to adjust the height of the filter cartridge 31 in the initial state according to the actual situation, a resistance adjustment unit 35 is provided on the sleeve 341. The cross-section of the stirring rod 32 is elliptical. The resistance adjustment unit 35 includes a connecting frame 351 slidably connected to the outside of the sleeve 341. The outer side of the sleeve 341 is rotatably connected to an adapter seat 353 fixed to the stirring rod 32. The bottom end of the connecting frame 351 is hinged to a connecting rod 352. The eccentric position on one side of the adapter seat 353 is hinged to the connecting rod 352. The top of the sleeve 341 penetrates the top wall of the tank 21 and is threadedly connected to a threaded sleeve 36 rotatably connected to the connecting frame 351. The wastewater level in the tank 21 is not higher than the connecting frame 351.

[0033] In the initial state, the stirring rod 32 has the smallest width in the vertical direction, and experiences the least resistance when rotating with the sleeve 341 and the main shaft 33. Manually tightening the threaded sleeve 36 moves the connecting frame 351 upward, which in turn pulls the connecting frame 351 upward, causing the adapter 353 and the stirring rod 32 to deflect. This increases the width of the stirring rod 32 in the vertical direction, thereby increasing the resistance experienced by the stirring rod 32 during rotation and achieving height adjustment of the filter cartridge 31 in the initial state.

[0034] In this invention, the stirring rod 32 not only stirs the waste liquid to ensure uniform distribution and improve filtration efficiency, but also provides resistance, allowing for adjustment of the filtration area of ​​the pre-filtration mechanism 11. Furthermore, by adjusting the angle of the stirring rod 32 through the resistance adjustment unit 35, the effective filtration area of ​​the filter cartridge 31 in its initial state can be adjusted, facilitating control of the filtration effect based on the actual concentration of the waste liquid and further improving the overall performance.

[0035] Furthermore, multiple sets of adapter seats 353 can be provided, with several adapter seats 353 arranged in a row in each set. A vertically arranged connecting rod 37 is hinged between two adjacent adapter seats 353 in each row. Both ends of the connecting rod 37 are hinged to eccentric positions on one side of the two adapter seats 353. When the uppermost adapter seat 353 deflects, it drives the connecting rod 37 to move upward, causing the next adapter seat 353 to deflect synchronously in the same direction, thereby realizing the angle adjustment of each stirring rod 32.

[0036] Reference Figure 9 ,and Figure 10 A transmission unit 1 42 and a transmission unit 2 43 are connected between the motor 41 and the main shaft 33. Transmission unit 1 42 includes a positioning disk 421 rotatably connected to the top of the tank 21 and fixed to the drive shaft of the motor 41. A turntable 422 is slidably connected to the top of the main shaft 33. A pusher 423 is eccentrically fixed to the top surface of the positioning disk 421. The pusher 423 corresponds to the notch position of the positioning disk 421. The positioning disk 421 drives the pusher 423 to perform circular motion. After the pusher 423 enters the groove of the turntable 422, its continued rotation pushes the inner wall of the groove, causing the turntable 422 to rotate, thus rotating the main shaft 33. During this process, the notch of the positioning disk 421 faces the arc-shaped groove on the outer side of the turntable 422, without restricting the rotation of the turntable 422. After the pusher 423 pushes the turntable 422 to rotate 90 degrees, it disengages from the slide groove. At this time, the outer part of the positioning plate 421, except for the notch, enters the arc-shaped groove of the turntable 422, positioning the turntable 422 and preventing it from rotating. According to this design, the transmission unit 42 enables the motor 41 to drive the main shaft 33 to perform intermittent rotational motion, with each rotation angle being 90 degrees.

[0037] The transmission unit 43 includes a gear 431 fixed to the bottom of the positioning disk 421, and a gear 432 slidably connected to the top of the main shaft 33. When gear 431 and gear 432 mesh, the motor 41 drives the positioning disk 421 to rotate, and the main shaft 33 can be driven to rotate at a constant speed through the transmission of gear 431 and gear 432.

[0038] A connecting pipe 44 is fixed between the turntable 422 and the second gear 432. The connecting pipe 44 is sleeved on the top of the main shaft 33 and fixed to the main shaft 33 with bolts. By adjusting the position of the connecting pipe 44 fixed on the main shaft 33, the turntable 422 can be engaged with the push column 423 through the slide groove or the first gear 431 can be engaged with the second gear 432, thus switching the motion mode of the motor 41 driving the main shaft 33.

[0039] When motor 41 drives main shaft 33 to rotate at a constant speed through transmission unit 43, the effective filtration area of ​​filter cartridge 31 changes with the viscosity of waste liquid according to the above principle, thus stabilizing the output of pre-filtration mechanism 11. When motor 41 drives main shaft 33 to rotate intermittently through transmission unit 42, the resistance of stirring rod 32 changes periodically, causing filter cartridge 31 to continuously reciprocate vertically. During the shutdown cleaning phase, the filter cartridge 31 washes the waste liquid on its surface, reducing waste liquid adhesion.

[0040] Reference Figure 3 , Figure 4 and Figure 5 An auxiliary cleaning structure 50 is also provided. The bottom end of the sleeve 341 penetrates the top wall of the filter cartridge 21 and extends to the bottom inside the filter cartridge 21. The auxiliary cleaning structure 50 includes a docking plate 1 51 fixed to the bottom end of the sleeve 341 and a docking plate 2 53 fixed to the inner wall of the filter cartridge 22. The docking plate 1 51 and the docking plate 2 53 are vertically aligned, and a fitting block 52 is fixed on the opposite side of the docking plate 1 51 and the docking plate 2 53. A mounting base 54 is fixed inside the tank body 21, and the filter cartridge 22 is rotatably mounted on the top of the mounting base 54.

[0041] During the shutdown and cleaning phase, the waste liquid in tank 21 is drained and clean water is injected. The motor 41 is controlled to increase its speed, so that the resistance of the stirring rod 32 reaches its maximum. The sleeve 341 drives the filter cartridge 2 31 to rise to its highest position. The sleeve 341 drives the docking plate 1 51 to move upward, so that the interlocking block 52 of docking plate 1 51 and docking plate 2 53 interlock. The main shaft 33 drives the filter cartridge 1 22 and filter cartridge 2 31 to rotate at high speed together through the slider 342, sleeve 341, docking plate 1 51, interlocking block 52 and docking plate 2 53. The impurities on the filter cartridge 1 22 and filter cartridge 2 31 are thrown out by centrifugal force, which improves the cleaning effect of the filter cartridge 1 22 and filter cartridge 2 31 and extends their service life.

[0042] A drain pipe 55 is fixed at the bottom of the tank 21. Valves are installed on both the liquid outlet pipe 23 and the drain pipe 55. Wastewater generated during the shutdown and cleaning phase is discharged through the drain pipe 55 for separate treatment.

[0043] During the shutdown and cleaning phase, the valve on the outlet pipe 23 is closed, and the valve on the drain pipe 55 is opened, allowing clean water to pass through the tank 21 and fill the interior of filter cartridge 22 and filter cartridge 31. During this process, filter cartridge 31 is controlled to reciprocate according to the aforementioned principle. As filter cartridge 31 descends, the water pressure inside filter cartridges 22 and 31 increases, forcing water out through the filter holes under pressure, backwashing impurities in the filter holes. The discharged impurities mix with the clean water and are discharged through the drain pipe 55, preventing filter cartridge 31 from drawing impurities back into the filter holes during its ascent. This design, through periodic pressure impact on the filter holes of filter cartridges 22 and 31, significantly improves the cleaning effect, prevents impurities from clogging the filter holes, and further extends the service life of filter cartridges 22 and 31.

[0044] In addition, a scraper 61 is fixed at the bottom of filter cartridge 21, which contacts the outer wall of filter cartridge 12. When filter cartridge 231 moves longitudinally and rotates relative to filter cartridge 122, the scraper 61 can scrape off the impurities attached to the surface of the lower filtration section of filter cartridge 12, promote the falling of impurities, avoid local blockage of the filtration surface of filter cartridge 12, and further improve the filtration stability of pre-filtration mechanism 11.

[0045] Working principle: In the initial state, the tank 21 is filled with paint wastewater of a certain concentration. Gear 1 431 and Gear 2 432 mesh, and motor 41 drives positioning plate 421 and gear 1 431 to rotate at a constant speed. Through gear 2 432, the main shaft 33, slider 342, sleeve 341, adapter 353, stirring rod 32 and filter cartridge 2 31 rotate at a constant speed. At this time, under the action of wastewater resistance, slider 342 is in the middle of the spiral groove, spring 343 is further compressed, and the upper part of filter cartridge 2 31 is higher than filter cartridge 1 22. After the wastewater in tank 21 is filtered by the filter surfaces of filter cartridge 1 22 and filter cartridge 2 31, it is discharged to the next treatment device through the liquid outlet pipe 23.

[0046] When the viscosity of the wastewater increases, the stirring rod 32 encounters greater resistance during its rotation and stirring process. The sleeve 341 ascends along the main shaft 33 via the spiral groove and slider 342, further compressing the spring 343 and simultaneously causing the filter cartridge 31 to move upwards, increasing its filtration area. Conversely, when the viscosity of the wastewater decreases, the resistance experienced by the stirring rod 32 and the flow adjustment structure 34 decreases. The spring 343 extends, pressing the sleeve 341 downwards and causing the filter cartridge 31 to move downwards. This results in more of the filter cartridge 31's filtration area being blocked by the upper connecting section of the filter cartridge 22, reducing its filtration area. This invention adjusts the effective filtration area based on changes in wastewater viscosity to stabilize the filtration efficiency of the pre-filtration mechanism 11 and maintain a stable output flow.

[0047] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the present invention's concept of a water-soluble solvent paint waste liquid recycling and treatment device for automotive painting workshops, should be covered within the scope of protection of the present invention.

Claims

1. A device for recycling and treating water-soluble solvent paint waste liquid in an automotive painting workshop, comprising a pre-filtration mechanism (11), an ultrafiltration system (12), a nanofiltration system (13), and a reverse osmosis system (14) arranged in series, wherein, The pre-filtration mechanism (11) includes a tank (21), a filter cartridge (22) is provided inside the tank (21), and a liquid outlet pipe (23) is fixed at the bottom of the tank (21). It is characterized by further comprising: The balanced filtration assembly (30) includes a filter cartridge (31) and a stirring rod (32) disposed inside the tank (21). The filter cartridge (22) consists of an upper connecting section and a lower filtration section. The filter cartridge (31) is sleeved on the outside of the upper connecting section. A main shaft (33) is rotatably connected inside the tank (21). A flow rate adjustment structure (34) is provided on the main shaft (33). The drive assembly (40) includes a motor (41) fixedly mounted on the top of the tank (21). The flow rate adjustment structure (34) adjusts the height of the filter cartridge (31) by the rotational resistance of the stirring rod (32), so that the effective filtration area of ​​the filter cartridge (31) matches the viscosity of the paint waste liquid, and stabilizes the discharge flow rate of the pre-filtration mechanism (11).

2. The device for recycling and treating water-soluble solvent paint waste liquid in an automotive painting workshop according to claim 1, characterized in that, The flux adjustment structure (34) includes a sleeve (341) sleeved outside the main shaft (33) and fixed to the filter cartridge (31). A slider (342) embedded in the spiral groove of the inner wall of the sleeve (341) is fixed on the outer wall of the main shaft (33). A spring (343) is provided between the inner wall of the sleeve (341) and the outer wall of the main shaft (33).

3. The device for recycling and treating water-soluble solvent paint waste liquid in an automotive painting workshop according to claim 1, characterized in that, The motor (41) and the main shaft (33) are connected by a transmission unit one (42) and a transmission unit two (43). The transmission unit one (42) includes a positioning disk (421) rotatably connected to the top of the tank (21) and fixed to the drive shaft of the motor (41). The top of the main shaft (33) is slidably connected to a turntable (422), and a push column (423) is eccentrically fixed to the top surface of the positioning disk (421).

4. The device for recycling and treating water-soluble solvent paint waste liquid in an automotive painting workshop according to claim 3, characterized in that, The transmission unit 2 (43) includes a gear 1 (431) fixed to the bottom of the positioning disk (421), and a gear 2 (432) is slidably connected to the top of the main shaft (33).

5. The device for recycling and treating water-soluble solvent paint waste liquid in an automotive painting workshop according to claim 4, characterized in that, A connecting pipe (44) is fixed between the turntable (422) and the gear (432). The connecting pipe (44) is sleeved on the top of the main shaft (33) and fixed to the main shaft (33) by bolts.

6. The device for recycling and treating water-soluble solvent paint waste liquid in an automotive painting workshop according to claim 2, characterized in that, The sleeve (341) is provided with a resistance adjustment unit (35). The resistance adjustment unit (35) includes a connecting frame (351) slidably connected to the outside of the sleeve (341). The outside of the sleeve (341) is rotatably connected to an adapter seat (353) fixed to the stirring rod (32). A connecting rod (352) is hinged between the connecting frame (351) and the adapter seat (353).

7. The device for recycling and treating water-soluble solvent paint waste liquid in an automotive painting workshop according to claim 6, characterized in that, The top of the sleeve (341) is threadedly connected to a threaded sleeve (36) that is rotatably connected to the connecting frame (351). Several adapter seats (353) are arranged in rows, and a connecting rod (37) is hinged between two adjacent adapter seats (353) in each row.

8. The device for recycling and treating water-soluble solvent paint waste liquid in an automotive painting workshop according to claim 2, characterized in that, It also includes an auxiliary cleaning structure (50), which includes a first docking plate (51) fixed to the bottom of the sleeve (341) and a second docking plate (53) fixed to the inner wall of the first filter cylinder (22). The first docking plate (51) and the second docking plate (53) are fixed with fitting blocks (52) on opposite sides. The bottom of the first filter cylinder (22) is rotatably connected to a mounting base (54) fixed to the tank body (21).

9. A device for recycling and treating water-soluble solvent paint waste liquid in an automotive painting workshop according to claim 1, characterized in that, The bottom of the tank (21) is fixed with a drain pipe (55), and valves are installed on both the liquid outlet pipe (23) and the drain pipe (55).

10. A device for recycling and treating water-soluble solvent paint waste liquid in an automotive painting workshop according to claim 1, characterized in that, The bottom of the second filter cartridge (31) is fixed with a scraper (61) that contacts the outer wall of the first filter cartridge (22).

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