Aluminum foil wastewater treatment system and process

Abstract

The invention discloses an aluminum foil wastewater treatment system and process, and belongs to the field of wastewater treatment.The aluminum foil wastewater treatment system comprises a wastewater collection pool, pretreatment equipment, an ultrafiltration system, a nanofiltration system, a recovery pool and an electrolytic bath, and a water outlet of the wastewater collection pool is communicated with the pretreatment equipment; a supernatant outlet of the pretreatment equipment is communicated with the ultrafiltration system, a produced water outlet of the ultrafiltration system is communicated with the nanofiltration system, a produced water outlet of the nanofiltration system is communicated with the recovery pool, and a concentrated water outlet of the nanofiltration system is communicated with the electrolytic bath. According to the aluminum foil wastewater treatment system and process, resourceful treatment of aluminum foil wastewater is achieved, hydrochloric acid and metal aluminum are recycled, and the quality of effluent can meet the environmental protection requirement.

Description

Technical Field

[0001] The present invention belongs to the field of wastewater treatment, and particularly relates to an aluminum foil wastewater treatment system and process. Background Art

[0002] Due to its excellent barrier properties, thermal conductivity, flexibility, and recyclability, aluminum foil has been widely used in many fields such as food packaging, electronics, medicine, and construction. With the continuous growth of the demand for aluminum foil in various industries, the production scale of aluminum foil is expanding day by day. However, a large amount of wastewater is generated during the production process of aluminum foil. If it is not effectively treated and recycled, it will not only cause serious environmental pollution but also lead to a great waste of resources.

[0003] The composition of aluminum foil wastewater is complex, and the main pollutants include hydrochloric acid, metallic aluminum (present in the form of aluminum ions), suspended solids, grease, and some other organic impurities. The presence of these pollutants makes the aluminum foil wastewater have strong acidity and high chemical oxygen demand (COD). If directly discharged, it will cause serious harm to the water ecological environment, soil, and groundwater.

[0004] Traditional aluminum foil wastewater treatment methods mainly adopt processes such as neutralization precipitation and coagulation precipitation to remove aluminum ions in the wastewater in the form of aluminum hydroxide precipitation, and then neutralize the wastewater to meet the discharge standards. Although this treatment method can reduce the concentration of aluminum ions and acidity in the wastewater, it has many drawbacks. On the one hand, a large amount of aluminum hydroxide precipitation needs to be further treated, increasing the treatment cost and environmental burden; on the other hand, the hydrochloric acid and metallic aluminum resources in the wastewater are not effectively recycled, resulting in a waste of resources. In addition, traditional treatment methods often have difficulty in completely removing organic impurities in the wastewater, making it difficult for the effluent quality to meet the increasingly strict environmental protection requirements. Summary of the Invention

[0005] The purpose of the present invention is to provide an aluminum foil wastewater treatment system and process to overcome at least one of the above-mentioned defects in the prior art.

[0006] To achieve this purpose, the present invention adopts the following technical solutions:

[0007] An aluminum foil wastewater treatment system provided by the present invention includes a wastewater collection tank, a pretreatment device, an ultrafiltration system, a nanofiltration system, a recovery tank, and an electrolytic cell. The water outlet of the wastewater collection tank is connected to the pretreatment device, the supernatant outlet of the pretreatment device is connected to the ultrafiltration system, the water production outlet of the ultrafiltration system is connected to the nanofiltration system, the water production outlet of the nanofiltration system is connected to the recovery tank, and the concentrated water outlet of the nanofiltration system is connected to the electrolytic cell.

[0008] Preferably, the pretreatment device includes a box body, a stirring assembly, a transmission assembly, a lifting member, and a lifting frame. The top of the box body is fixed with the stirring assembly and the lifting member. The stirring end of the stirring assembly is located inside the box body. The lifting member is drivingly connected to the stirring assembly through the transmission assembly. The lifting end of the lifting member is fixed with a lifting frame, and the lifting frame is located inside the box body.

[0009] Preferably, the stirring assembly includes a first bearing seat, a stirring shaft, and stirring blades. The first bearing seat is fixed to the top of the box body. The lower part of the stirring shaft passes through the first bearing seat and the top wall of the box body and extends into the box body to be fixed with two layers of stirring blades distributed at intervals up and down.

[0010] Preferably, the lifting member includes a motor, a first rotating shaft, a first bevel gear, a second bevel gear, a second bearing seat, a second rotating shaft, a cam, a connecting frame, a guide sleeve, and a guide rod. The motor and the second bearing seat are fixed to the top of the box body. The top of the motor is fixed with the first rotating shaft, and the top end of the first rotating shaft is fixed with the first bevel gear. The left end of the second rotating shaft is fixed with the second bevel gear, and the second bevel gear meshes with the first bevel gear. The right end of the second rotating shaft is fixed with the cam. Guide sleeves are fixed to both the left and right sides of the top of the box body. The bottom end of the guide rod passes through the guide sleeve and the top wall of the box body and extends into the box body to be fixed with the lifting frame. The two guide rods on the left and right are connected by a connecting frame, and the cam contacts the bottom wall of the connecting frame.

[0011] Preferably, the transmission assembly includes a driving wheel, a driven wheel, and a transmission belt. The driving wheel is fixed to the first rotating shaft, the driven wheel is fixed to the stirring shaft, and the driving wheel and the driven wheel are drivingly connected by the transmission belt.

[0012] Preferably, the lifting frame includes a ring sleeve, a first cross plate, a second cross plate, and a vertical plate. First cross plates are fixed to both the left and right side walls of the ring sleeve. The outer ends of the first cross plates are fixed with vertical plates. The inner side of the lower part of the vertical plate is fixed with the second cross plate. The stirring blade in the upper layer is located between the first cross plate and the second cross plate. The second cross plate is located between the upper and lower layers of stirring blades. The stirring shaft passes through the ring sleeve, and the bottom end of the guide rod is connected to the top end of the vertical plate.

[0013] Preferably, it further includes a medicine storage box, a third bearing, a vertical pipe, a sealing ring, and a first valve. The medicine storage box is fixed to the top of the box body. The bottom of the medicine storage box is fixedly communicated with a vertical pipe. The vertical pipe is provided with a first valve. The inside of the stirring shaft has a first cavity. A third bearing is fixed above the inside of the first cavity. The bottom end of the vertical pipe passes through the third bearing. A sealing ring is arranged between the vertical pipe and the side wall of the stirring shaft. The inside of the stirring blade has a second cavity communicated with the first cavity. First through holes communicated with the second cavity are provided on both the front and rear side walls of the stirring blade.

[0014] Preferably, it further includes an air pump, a connecting pipe, and a second valve. An air pump is fixed to the top of the box body. The right side of the air outlet pipe of the air pump is fixedly communicated with a connecting pipe. The right end of the connecting pipe is fixedly communicated with the vertical pipe, and the connection part is located below the first valve. The connecting pipe is provided with a second valve.

[0015] Preferably, it further includes a flexible pipe and a third valve. The side wall of the collar has a third cavity. The interiors of the first horizontal plate, the second horizontal plate, and the vertical plate all have a fourth cavity. The fourth cavity of the first horizontal plate communicates with the third cavity and the fourth cavity of the vertical plate. The fourth cavity of the vertical plate communicates with the fourth cavity of the vertical plate and the second vertical plate. The front and rear side walls of the first horizontal plate, the second horizontal plate, and the vertical plate all have a second through hole communicating with the fourth cavity inside them. One end of the flexible pipe is fixedly communicated with the left side of the air outlet pipe of the air pump, and the other end of the flexible pipe is communicated with the fourth cavity of the first horizontal plate. The flexible pipe is provided with a third valve.

[0016] The present invention also provides an aluminum foil wastewater treatment process, which is treated by using the above-mentioned aluminum foil wastewater treatment system, and includes the following steps: sending the aluminum foil wastewater into the wastewater collection tank, after homogenizing and equalizing the amount in the wastewater collection tank, sending it into the pretreatment equipment for pretreatment, sending the supernatant after pretreatment into the ultrafiltration system for ultrafiltration treatment, sending the produced water obtained from the ultrafiltration treatment into the nanofiltration system for nanofiltration treatment, sending the produced water obtained from the nanofiltration treatment into the recovery tank to recover hydrochloric acid, and sending the concentrated water obtained from the nanofiltration treatment into the electrolytic cell for electrolytic treatment to obtain metallic aluminum.

[0017] The beneficial effects of the present invention are as follows:

[0018] 1. Realize the resource treatment of aluminum foil wastewater, recover hydrochloric acid and metallic aluminum, and the effluent water quality can meet the environmental protection requirements.

[0019] 2. Through the setting of the stirring assembly combined with the lifting member and the lifting frame, not only the mixing is made sufficient by the stirring assembly, but also while stirring, combined with the liftable lifting frame, the liquid is disturbed in the vertical direction, breaking the stratification phenomenon existing in the vertical direction of the water body, making the mixed liquid at different heights fully blend, ensuring the uniform distribution of the coagulant within the entire water body height range, improving the coagulation reaction efficiency, and forming a complex flow field. This complex flow field makes the flow path of the liquid more diverse, increasing the collision chance between fluid micro-masses. The water flows in different directions and speeds intersect with each other, enabling the coagulant to contact the pollutant particles in the wastewater more frequently, thereby promoting the progress of the coagulation and flocculation reactions and contributing to the formation of larger and denser flocs.

[0020] 3. During the formation of the flocs, the up and down movement of the lifting frame changes the speed and direction of the water flow, making the floc particles move in different water flow environments. It brings the particles originally in different positions together, increasing the collision probability between the particles and promoting the growth and aggregation of the flocs.

[0021] 4. The rotation of the stirring blades combined with the lifting of the lifting frame applies a certain shear force to the flocs, making the arrangement of particles inside the flocs more compact and orderly. Such well-structured flocs have better sedimentation performance, which is beneficial to the subsequent solid-liquid separation process, reducing the sedimentation time and floor area.

[0022] 5. The water flow fluctuations generated during the movement of the lifting frame can also scour the wall surface of the box body. It can reduce the adhesion and accumulation of flocs and impurities on the wall surface, keep the box wall clean, prevent the adverse impact of wall scaling on the coagulation effect, and maintain a good water flow state inside the box body.

[0023] 6. Only one driving source (motor) is required to realize the reciprocating up and down movement of the lifting frame and the continuous stirring operation of the stirring blades. Linking the two actions can disturb the liquid while stirring, effectively ensuring the sufficiency of the coagulation sedimentation process.

[0024] 7. The movement of the first cross plate and the second cross plate generates additional disturbances to the liquid around the stirring blades, making the eddies formed by the stirring of the stirring blades more complex.

[0025] 8. The chemical dosing operation is directly carried out from the stirring end while stirring, which can ensure that the coagulant can be quickly and evenly dispersed in the wastewater in the box body.

[0026] 9. While stirring and mixing, the laminar flow state of the liquid is broken by the ejected air flow, making the coagulant and the like more quickly and evenly dispersed in the mixed liquid.

[0027] 10. The movement trajectories of the bubbles are complex and changeable. Interacting with the water flow generated by the stirring blades and the lifting frame, it further increases the flow complexity of the mixed liquid. Such a complex flow field enables the liquid in different regions to be more fully mixed, reducing the possible concentration gradient and velocity gradient in the mixed liquid, and making the coagulation reaction proceed under more uniform conditions.

[0028] 11. The bubbles generated by the injected air flow can serve as the core of aggregation, attracting the colloidal particles and fine suspended solids in the wastewater. These particles aggregate on the surface of the bubbles and gradually form tiny flocs. With the rising of the bubbles and the agitation of the stirring blades, more particles are adsorbed onto the flocs, promoting the growth of the flocs.

[0029] 12. The bubbles generate a certain buoyancy and impact force on the flocs during the rising process, making the flocs continuously subjected to external forces during the formation process. This external force helps the particles inside the flocs to combine more tightly, enhancing the structural strength of the flocs.

[0030] 13. The injected gas forms sufficient dissolved oxygen, which helps to promote some oxidation reactions in water. Some pollutants are more easily removed by the coagulant under aerobic conditions. For example, some reducing substances can be oxidized to a form that is more easily precipitated under the action of dissolved oxygen. In addition, dissolved oxygen can also inhibit the growth of some harmful microorganisms and prevent them from having a negative impact on the coagulation process.

[0031] 14. Open or close each valve according to actual usage requirements to adapt to different operation needs, with high flexibility.

[0032] 15. When the gas is ejected from the first through-hole and the second through-hole, it will have a certain scouring effect on the surfaces of the stirring blades and the lifting frame. This can prevent the flocs and impurities from adhering and accumulating on the surfaces of the stirring blades and the lifting frame, keep them clean, and ensure normal operation. Description of the Drawings

[0033] Figure 1 is the system block diagram of the present invention.

[0034] Figure 2 is the schematic structural diagram of the first state of the pretreatment equipment of the present invention.

[0035] Figure 3 is the partial front view structural diagram of the stirring assembly of the present invention.

[0036] Figure 4 is the schematic structural diagram of the cooperation of the lifting member, the transmission assembly, and the stirring assembly of the present invention.

[0037] Figure 5 is the right view structural diagram of the second rotating shaft and the cam of the present invention.

[0038] Figure 6 is the sectional view structural diagram of the lifting frame of the present invention.

[0039] Figure 7 is the schematic structural diagram of the cooperation of the third bearing, the vertical pipe, the sealing ring, and the stirring shaft of the present invention.

[0040] Figure 8 is the partial front view structural diagram of the present invention.

[0041] Figure 9 is the partial sectional view structural diagram of the stirring assembly of the present invention.

[0042] Figure 10 is the schematic structural diagram of the second state of the pretreatment equipment of the present invention.

[0043] The reference signs in the drawings are: 100 - wastewater collection tank, 200 - pretreatment equipment, 300 - ultrafiltration system, 400 - nanofiltration system, 500 - recovery tank, 600 - electrolytic cell, 1 - box body, 2 - stirring assembly, 3 - transmission assembly, 4 - lifting member, 5 - lifting frame, 21 - first bearing seat, 22 - stirring shaft, 23 - stirring blade, 41 - motor, 42 - first rotating shaft, 43 - first bevel gear, 44 - second bevel gear, 45 - second bearing seat, 46 - second rotating shaft, 47 - cam, 48 - connecting frame, 49 - guide sleeve, 410 - guide rod, 31 - driving wheel, 32 - driven wheel, 33 - transmission belt, 51 - collar, 52 - first cross plate, 53 - second cross plate, 54 - vertical plate, 6 - chemical storage tank, 7 - third bearing, 8 - vertical pipe, 9 - sealing ring, 10 - first valve, 221 - first cavity, 231 - second cavity, 232 - first through hole, 11 - air pump, 12 - connecting pipe, 13 - second valve, 14 - hose, 15 - third valve, 511 - third cavity, 55 - fourth cavity, 56 - second through hole. Detailed implementation manners

[0044] The present invention will be further described below in conjunction with the drawings and the detailed implementation manners.

[0045] Contents not described in detail in this specification belong to the prior art well-known to those skilled in the art. In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention. In addition, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0046] As Figures 1 to 10 shown, a kind of aluminum foil wastewater treatment system provided in this embodiment includes a wastewater collection tank 100, a pretreatment equipment 200, an ultrafiltration system 300, a nanofiltration system 400, a recovery tank 500, and an electrolytic cell 600. The water outlet of the wastewater collection tank 100 is communicated with the pretreatment equipment 200, the supernatant outlet of the pretreatment equipment 200 is communicated with the ultrafiltration system 300, the water production outlet of the ultrafiltration system 300 is communicated with the nanofiltration system 400, the water production outlet of the nanofiltration system 400 is communicated with the recovery tank 500, and the concentrated water outlet of the nanofiltration system 400 is communicated with the electrolytic cell 600.

[0047] This embodiment also provides an aluminum foil wastewater treatment process, which is treated by the above-mentioned aluminum foil wastewater treatment system, including the following steps:

[0048] The aluminum foil wastewater (mainly containing 1% HCL and 6% aluminum chloride) is sent into the wastewater collection tank 100. After being homogenized and equalized in the wastewater collection tank 100 for a period of time, it is sent into the pretreatment equipment 200, and a coagulant is added for pretreatment, so that impurities such as colloids and fine suspended solids in the wastewater are coagulated into larger particulate matters and removed by precipitation. The supernatant after pretreatment is sent into the ultrafiltration system 300 for ultrafiltration treatment. Since pretreatment is carried out before ultrafiltration treatment, most of the colloids, fine suspended solids and other impurities are removed, reducing the amount of impurities entering the ultrafiltration system 300, thus reducing the risk of ultrafiltration membrane pollution, extending the service life of the ultrafiltration membrane, and reducing the frequency of membrane cleaning and replacement. After pretreatment, most of the suspended and part of the dissolved pollutants in the wastewater are removed, and then it enters the ultrafiltration system 300 for further filtration, so that the ultrafiltration system 300 can effectively intercept the remaining suspended solids, colloids, macromolecular organic matters, etc., thus ensuring the water quality of the ultrafiltration produced water. The produced water obtained by ultrafiltration treatment is sent into the nanofiltration system 400 for nanofiltration treatment. Under the action of the pressure difference driving force, divalent and polyvalent ions in the wastewater are intercepted, so that the main component passing through the nanofiltration membrane is hydrochloric acid, thus achieving the separation and purification of hydrochloric acid. The produced water obtained by nanofiltration treatment is sent into the recovery tank 500 to recover hydrochloric acid for reuse in the workshop. Since divalent and polyvalent ions and the like are intercepted on the concentrated water side of the nanofiltration system 400, the concentrated water is mainly a concentrated solution of aluminum chloride. The small molecular organic matters in the wastewater are removed by the nanofiltration system 400, and cooperate with the ultrafiltration system 300 to completely remove the organic impurities in the wastewater. The concentrated water obtained by nanofiltration treatment is sent into the electrolytic cell 600 for electrolytic treatment. A reduction reaction occurs at the cathode, and aluminum ions gain electrons to generate metallic aluminum, and the high-purity metallic aluminum obtained on the cathode is collected. In this way, the resource treatment of aluminum foil wastewater is realized, hydrochloric acid and metallic aluminum are recovered, and the effluent water quality can meet the environmental protection requirements.

[0049] Among them, the pretreatment equipment 200 includes a box body 1, a stirring assembly 2, a transmission assembly 3, a lifting member 4, and a lifting frame 5. The top of the box body 1 is fixed with a stirring assembly 2 and a lifting member 4. The stirring end of the stirring assembly 2 is located inside the box body 1. The lifting member 4 is in transmission connection with the stirring assembly 2 through the transmission assembly 3. The lifting end of the lifting member 4 is fixed with a lifting frame 5, and the lifting frame 5 is located inside the box body 1.

[0050] To ensure the improvement of the treatment effect of the ultrafiltration system 300, it is necessary to ensure a sufficient coagulation and sedimentation process so that as many large particles as possible can settle down. If the sedimentation is not complete and too many large particles enter the ultrafiltration system 300, they will accumulate on the surface of the ultrafiltration membrane. Although it will not block the membrane pores as severely as fine particles, it will also affect the operation stability of the ultrafiltration system 300. Therefore, through the setting of the stirring assembly 2 in combination with the lifting member 4 and the lifting frame 5, the present invention not only makes the mixing sufficient through the stirring assembly 2, but also combines the liftable lifting frame 5 while stirring to disturb the liquid in the vertical direction, breaking the stratification phenomenon existing in the vertical direction of the water body, enabling the mixed liquid at different heights to be fully blended, ensuring the uniform distribution of the coagulant within the entire water body height range, and improving the coagulation reaction efficiency. And a complex flow field is formed. This complex flow field makes the flow path of the liquid more diversified, increasing the collision opportunities between fluid microclusters. The water flows in different directions and speeds are intertwined, enabling the coagulant to come into contact with the pollutant particles in the wastewater more frequently, thereby promoting the coagulation and flocculation reactions and contributing to the formation of larger and denser flocs. During the formation of the flocs, the up-and-down movement of the lifting frame 5 changes the speed and direction of the water flow, causing the floc particles to move in different water flow environments. It brings the particles originally in different positions together, increasing the collision probability between the particles and promoting the growth and aggregation of the flocs. Moreover, a certain shear force is applied to the flocs, making the arrangement of the particles inside the flocs more compact and orderly. Such well-structured flocs have better sedimentation performance, which is beneficial to the subsequent solid-liquid separation process, reducing the sedimentation time and floor area. In addition, the water flow fluctuations generated during the movement of the lifting frame 5 can also scour the wall surface of the box body 1. It can reduce the adhesion and accumulation of flocs and impurities on the wall surface, keep the box wall clean, prevent the adverse impact of wall scaling on the coagulation effect, and maintain a good water flow state inside the box body 1.

[0051] Among them, the stirring assembly 2 includes a first bearing seat 21, a stirring shaft 22, and stirring blades 23. The first bearing seat 21 is fixed to the top of the box body 1. The lower part of the stirring shaft 22 passes through the first bearing seat 21 and the top wall of the box body 1 and extends into the interior of the box body 1 to be fixed with two layers of stirring blades 23 distributed at intervals up and down. The stirring shaft 22 rotates to drive the stirring blades 23 to rotate, improving the mixing efficiency.

[0052] Among them, the lifting member 4 includes a motor 41, a first rotating shaft 42, a first bevel gear 43, a second bevel gear 44, a second bearing seat 45, a second rotating shaft 46, a cam 47, a connecting frame 48, a guide sleeve 49, and a guide rod 410. The motor 41 and the second bearing seat 45 are fixed to the top of the box body 1. The first rotating shaft 42 is fixed to the top of the motor 41. The first bevel gear 43 is fixed to the top end of the first rotating shaft 42. The second bevel gear 44 is fixed to the left end of the second rotating shaft 46. The second bevel gear 44 meshes with the first bevel gear 43. The cam 47 is fixed to the right end of the second rotating shaft 46. Guide sleeves 49 are fixed to both the left and right sides of the top of the box body 1. The bottom end of the guide rod 410 passes through the guide sleeve 49 and the top wall of the box body 1 and extends into the box body 1 to be fixed to the lifting frame 5. The left and right guide rods 410 are connected by a connecting frame 48. The cam 47 contacts the bottom wall of the connecting frame 48. The transmission assembly 3 includes a driving wheel 31, a driven wheel 32, and a transmission belt 33. The driving wheel 31 is fixed to the first rotating shaft 42. The driven wheel 32 is fixed to the stirring shaft 22. The driving wheel 31 and the driven wheel 32 are connected by a transmission belt 33 for transmission connection.

[0053] When the motor 41 rotates, it drives the first rotating shaft 42 to rotate, causing the first bevel gear 43 to rotate, and then the second bevel gear 44 to rotate, driving the second rotating shaft 46 to rotate, causing the cam 47 to rotate. Under the action of the cam 47 and gravity, the connecting frame 48 moves up and down reciprocally, driving the guide rod 410 to move up and down reciprocally, and then driving the lifting frame 5 to move up and down reciprocally. While the first rotating shaft 42 rotates, it drives the driving wheel 31 to rotate, and drives the driven wheel 32 to rotate through the transmission belt 33, causing the stirring shaft 22 to rotate. In this way, only one driving source (the motor 41) is needed to achieve the up and down reciprocating movement of the lifting frame 5 and the continuous stirring operation of the stirring blades 23, link the two actions, disturb the liquid while stirring, and effectively ensure the full coagulation and precipitation process.

[0054] Among them, the lifting frame 5 includes a ring sleeve 51, a first cross plate 52, a second cross plate 53, and a vertical plate 54. First cross plates 52 are fixed to the left and right side walls of the ring sleeve 51. A vertical plate 54 is fixed to the outer end of the first cross plate 52. A second cross plate 53 is fixed to the inner side of the lower part of the vertical plate 54. The stirring blade 23 in the upper layer is located between the first cross plate 52 and the second cross plate 53. The second cross plate 53 is located between the stirring blades 23 in the upper and lower layers. The stirring shaft 22 passes through the ring sleeve 51. The bottom end of the guide rod 410 is connected to the top end of the vertical plate 54. The spaces between the first cross plate 52 and the stirring blade 23 in the upper layer, between the stirring blade 23 in the upper layer and the second cross plate 53, and between the second cross plate 53 and the stirring blade 23 in the lower layer form special flow field regions during the movement of the components. The movement of the first cross plate 52 and the second cross plate 53 generates additional disturbances to the liquid around the stirring blade 23, making the eddy currents formed by the stirring blade 23 more complex. This complex flow field increases the collision frequency between fluid microclusters, enabling the coagulant to come into more sufficient contact with the pollutant particles in the wastewater, thereby accelerating the coagulation and flocculation reactions.

[0055] Among them, it further includes a chemical storage tank 6, a third bearing 7, a vertical pipe 8, a sealing ring 9, and a first valve 10. The chemical storage tank 6 is fixed to the top of the box body 1. The bottom of the chemical storage tank 6 is fixedly communicated with a vertical pipe 8. The vertical pipe 8 is provided with a first valve 10. The inside of the stirring shaft 22 has a first cavity 221. A third bearing 7 is fixed above the inside of the first cavity 221. The bottom end of the vertical pipe 8 passes through the third bearing 7. A sealing ring 9 is arranged between the vertical pipe 8 and the side wall of the stirring shaft 22. The inside of the stirring blade 23 has a second cavity 231 communicated with the first cavity 221. First through holes 232 communicated with the second cavity 231 are provided on the front and rear side walls of the stirring blade 23.

[0056] When a coagulant needs to be added, the first valve 10 is opened, and the coagulant enters the vertical pipe 8 from the chemical storage tank 6, then enters the first cavity 221, and finally enters the box body 1 through the first through holes 232, directly performing the chemical addition operation from the stirring end while stirring. This can ensure that the coagulant can be quickly and evenly dispersed in the wastewater in the box body 1.

[0057] Among them, it further includes an air pump 11, a connecting pipe 12, and a second valve 13. The air pump 11 is fixed to the top of the box body 1. The right side of the air outlet pipe of the air pump 11 is fixedly communicated with a connecting pipe 12. The right end of the connecting pipe 12 is fixedly communicated with the vertical pipe 8, and the connection part is located below the first valve 10. The connecting pipe 12 is provided with a second valve 13.

[0058] When gas supply is required, the air pump 11 and the second valve 13 are opened. The gas enters the vertical pipe 8 through the connecting pipe 12, then enters the first cavity 221, and finally sprays out through the first through-hole 232. In this way, while stirring and mixing, the laminar flow state of the liquid is broken by the ejected air flow, enabling the coagulant and the like to be more rapidly and evenly dispersed in the mixed liquid. The movement trajectories of the bubbles are complex and changeable, interacting with the water flow generated by the stirring blades 23 and the lifting frame 5, further increasing the flow complexity of the mixed liquid. This complex flow field enables the liquids in different regions to be more fully mixed, reducing the possible concentration gradients and velocity gradients in the mixed liquid, and enabling the coagulation reaction to proceed under more uniform conditions. The bubbles generated by the injected air flow can serve as the cores of aggregation, attracting the colloidal particles and fine suspended solids in the wastewater. These particles accumulate on the surface of the bubbles and gradually form tiny flocs. With the rising of the bubbles and the agitation of the stirring blades 23, more particles are adsorbed onto the flocs, promoting the growth of the flocs. The bubbles generate a certain buoyancy and impact force on the flocs during the rising process, causing the flocs to be continuously affected by external forces during the formation process. This external force helps the particles inside the flocs to be more closely combined, enhancing the structural strength of the flocs. The flocs with stable structures are not easily broken during the subsequent precipitation process, which is beneficial to improving the solid-liquid separation effect. The injected gas forms sufficient dissolved oxygen, which helps to promote some oxidation reactions in the water. Some pollutants are more easily removed by the coagulant under aerobic conditions. For example, some substances with reducibility can be oxidized to forms that are more easily precipitated under the action of dissolved oxygen. In addition, dissolved oxygen can also inhibit the growth of some harmful microorganisms, preventing them from having a negative impact on the coagulation process.

[0059] Wherein, it further includes a hose 14 and a third valve 15. The side wall of the collar 51 has a third cavity 511, and the third cavity 511 is arranged around the collar 51. The interiors of the first cross plate 52, the second cross plate 53, and the vertical plate 54 all have a fourth cavity 55. The fourth cavity 55 of the first cross plate 52 communicates with the third cavity 511 and the fourth cavity 55 of the vertical plate 54. The fourth cavity 55 of the vertical plate 54 communicates with the fourth cavity 55 of the vertical plate 54 and the second vertical plate 54. The front and rear side walls of the first cross plate 52, the second cross plate 53, and the vertical plate 54 all have second through-holes 56 communicating with the fourth cavity 55 inside them. One end of the hose 14 is fixedly communicated with the left side of the air outlet pipe of the air pump 11, and the other end of the hose 14 is communicated with the fourth cavity 55 of the first cross plate 52. The hose 14 is provided with a third valve 15.

[0060] The third valve 15 can be opened while adding medicine, so that gas enters the fourth cavity 55 through the hose 14 and then sprays out from the second through-hole 56. Combining the operation of adding medicine while stirring can greatly improve the dispersion efficiency of the coagulant in the wastewater and enhance the mixing uniformity. The third valve 15 can also be opened while the second valve 13 is opened, or the third valve 15 can be opened when the second valve 13 and the first valve 10 are closed. The opening and closing of each valve are specifically determined according to the actual usage requirements to adapt to different operation needs, with high flexibility. When the gas sprays out from the first through-hole 232 and the second through-hole 56, it will have a certain scouring effect on the surfaces of the stirring blades 23 and the lifting frame 5. This can prevent flocs and impurities from adhering to and accumulating on the surfaces of the stirring blades 23 and the lifting frame 5, keep them clean, and ensure normal operation.

[0061] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An aluminum foil wastewater treatment system, characterized by: It includes wastewater collection tank, pretreatment equipment, ultrafiltration system, nanofiltration system, recovery tank, and electrolytic cell; The water outlet of the wastewater collection tank is connected to the pretreatment equipment; The supernatant outlet of the pretreatment device is in communication with the ultrafiltration system; The water output outlet of the ultrafiltration system is in communication with the nanofiltration system; The water production outlet of the nanofiltration system is communicated with the recovery tank, and the concentrated water outlet of the nanofiltration system is communicated with the electrolytic cell.

2. The aluminum foil wastewater treatment system according to claim 1, characterized in that: The pretreatment equipment includes a box body, a stirring assembly, a transmission assembly, a lifting member, and a lifting frame; A stirring assembly and a lifting member are fixed on the top of the box, and a stirring end of the stirring assembly is located inside the box; The lifting member is connected to the stirring assembly through a transmission assembly; A lifting frame is fixed to the lifting end of the lifting member, and the lifting frame is located inside the box body.

3. The aluminum foil wastewater treatment system according to claim 2, characterized in that: The stirring assembly includes a first bearing seat, a stirring shaft, and a stirring blade; A first bearing seat is fixed on the top of the box body, and the lower part of the stirring shaft passes through the first bearing seat and the top wall of the box body, and extends to the inside of the box body where two layers of stirring blades are fixed and spaced apart from each other.

4. The aluminum foil wastewater treatment system according to claim 3 is characterized in that: The lifting member includes a motor, a first rotating shaft, a first bevel gear, a second bevel gear, a second bearing seat, a second rotating shaft, a cam, a connecting frame, a guide sleeve, and a guide rod; A motor and a second bearing seat are fixed on the top of the box; A first rotating shaft is fixed on the top of the motor, and a first bevel gear is fixed on the top end of the first rotating shaft; A second bevel gear is fixed to the left end of the second rotating shaft, the second bevel gear is meshed with the first bevel gear, and a cam is fixed to the right end of the second rotating shaft; Guide sleeves are fixed on both left and right sides of the top of the box body, and the bottom end of the guide rod passes through the guide sleeves and the top wall of the box body and extends to the inside of the box body where the lifting frame is fixed; The left and right guide rods are connected by a connecting frame; The cam contacts the bottom wall of the connecting frame.

5. The aluminum foil wastewater treatment system according to claim 4, characterized in that: The transmission assembly includes a driving wheel, a driven wheel, and a transmission belt; The driving wheel is fixed to the first rotating shaft, the driven wheel is fixed to the stirring shaft, and the driving wheel and the driven wheel are connected via a transmission belt.

6. The aluminum foil wastewater treatment system according to claim 4, characterized in that: The lifting frame includes a ring sleeve, a first horizontal plate, a second horizontal plate, and a vertical plate; The left and right side walls of the ring sleeve are both fixed with a first horizontal plate, the outer end of the first horizontal plate is fixed with a vertical plate, and the inner side of the lower part of the vertical plate is fixed with a second horizontal plate; The stirring blades located at the upper layer are located between the first transverse plate and the second transverse plate, and the second transverse plate is located between the stirring blades at the upper and lower layers; The stirring shaft passes through the ring sleeve, and the bottom end of the guide rod is connected to the top end of the vertical plate.

7. The aluminum foil wastewater treatment system according to claim 6, characterized in that: Also includes a medicine storage box, a third bearing, a vertical pipe, a sealing ring, and a first valve; A medicine storage box is fixed on the top of the box body, a vertical pipe is fixedly connected to the bottom of the medicine storage box, and the vertical pipe is provided with a first valve; The stirring shaft has a first cavity inside, and a third bearing is fixed above the inside of the first cavity; The bottom end of the vertical pipe passes through the third bearing; A sealing ring is provided between the vertical tube and the side wall of the stirring shaft; The stirring blade has a second cavity inside that is connected to the first cavity; Both the front and rear side walls of the stirring blade have a first through hole communicating with the second cavity.

8. The aluminum foil wastewater treatment system according to claim 7, characterized in that: Also includes an air pump, a connecting pipe, and a second valve; An air pump is fixed on the top of the box body, a connecting pipe is fixedly connected to the right side of the air outlet pipe of the air pump, the right end of the connecting pipe is fixedly connected to the vertical pipe, and the connection point is located below the first valve; The connecting pipe is provided with a second valve.

9. The aluminum foil wastewater treatment system according to claim 8, characterized in that: Also includes a hose, and a third valve; The side wall of the ring sleeve has a third cavity; The first transverse plate, the second transverse plate, and the vertical plate all have a fourth cavity inside, and the fourth cavity of the first transverse plate is connected to the third cavity and the fourth cavity of the vertical plate; The fourth cavity of the vertical plate is connected to the fourth cavity of the vertical plate and the second vertical plate; The first horizontal plate, the second horizontal plate, and the front and rear side walls of the vertical plate all have second through holes communicating with the fourth cavities therein; One end of the hose is fixedly connected to the left side of the air outlet pipe of the air pump, and the other end of the hose is connected to the fourth cavity of the first horizontal plate; The hose is provided with a third valve.

10. A process for treating aluminum foil wastewater, characterized in that: The aluminum foil wastewater treatment system according to any one of claims 1 to 9 is used for treatment, comprising the following steps: The aluminum foil wastewater is sent to the wastewater collection pool, and after being homogenized and weighed in the wastewater collection pool, it is sent to the pretreatment equipment for pretreatment. The supernatant after pretreatment is sent to the ultrafiltration system for ultrafiltration treatment, and the produced water obtained by the ultrafiltration treatment is sent to the nanofiltration system for nanofiltration treatment. The produced water obtained by the nanofiltration treatment is sent to the recovery pool to recover hydrochloric acid, and the concentrated water obtained by the nanofiltration treatment is sent to the electrolytic cell for electrolysis to obtain metallic aluminum.

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