A system and method for treating 3,3'-dichlorobenzidine hydrochloride neutralized wastewater

Abstract

The present application relates to wastewater neutralization technical field, specifically to a kind of 3,3'-dichlorobenzidine hydrochloride neutralization wastewater treatment system and processing method, including neutralization tank, stirring unit, discharge pipe, PH sensor, liquid level sensor and cleaning assembly, cleaning assembly includes two filter plates, circulating pump, transfer unit and multiple first spray head, liquid is discharged from neutralization tank, and the filter cake, impurities or suspended solids are filtered through filter plate;Filtrate is transported to transfer unit by circulating pump;Filtrate is sprayed from multiple first spray head, and the filter cake, impurities or suspended solids adhered inside neutralization tank are washed down uniformly;Thus, the filtrate after neutralization is discharged and filtered, then the filter cake, impurities or suspended solids adhered are washed by using filtered filtrate backflow to neutralization tank, and then repeatedly circulating filtration, the filter cake, impurities or suspended solids inside are cleaned, and the quality of subsequent catalytic oxidation is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of wastewater neutralization technology, and in particular to a wastewater treatment system and method for neutralizing 3,3'-dichlorobenzidine hydrochloride. Background Technology

[0002] 3,3'-Dichlorobenzidine hydrochloride (DCB) is an important organic compound widely used in pigment production. In its preparation, DCB is typically produced by reducing o-nitrochlorobenzene under alkaline conditions, followed by a series of chemical reactions. However, this process generates a large amount of wastewater. To ensure the wastewater meets discharge standards, a catalytic oxidation method is usually used. This involves adding collected alkaline wastewater to neutralize the wastewater, creating a weakly alkaline environment. Impurities and suspended solids in the weakly alkaline wastewater are then filtered out before being transferred to a reactor filled with a highly efficient catalyst for catalytic oxidation, ultimately meeting discharge requirements.

[0003] In the aforementioned prior art, the highly alkaline wastewater of 3,3'-dichlorobenzidine hydrochloride is usually mixed inside a tank during neutralization. At this time, due to the presence of organic or inorganic matter in the wastewater, the neutralization reaction may cause polymerization or flocculation, generating a large amount of impurities and suspended solids. In order to ensure the quality of the neutralized wastewater and its smooth entry into the reactor to avoid clogging, the neutralized wastewater needs to be filtered. After the impurities and suspended solids are generated, they will adhere to the inner wall of the tank and the agitator. However, the current traditional method relies solely on setting up a filter screen during discharge, which cannot remove the impurities and suspended solids adhering to the tank. Over time, this will cause impurities to accumulate inside the tank, which can easily affect the wastewater neutralization operation and reduce neutralization efficiency and quality. Summary of the Invention

[0004] The purpose of this invention is to provide a wastewater treatment system and method for neutralizing 3,3'-dichlorobenzidine hydrochloride, which solves the problem that in the prior art, after impurities and suspended solids are generated, they will adhere to the inner wall of the tank and the agitator; however, the current traditional method only relies on setting up a filter screen during discharge, which cannot clean the impurities and suspended solids adhering to the tank. Over time, this will cause impurities to accumulate inside the tank, which can easily affect the wastewater neutralization operation and reduce the neutralization efficiency and quality.

[0005] To achieve the above objectives, the present invention provides a 3,3'-dichlorobenzidine hydrochloride neutralization wastewater treatment system, comprising a neutralization tank, a stirring unit, a discharge pipe, a pH sensor, a liquid level sensor, and a cleaning assembly. The stirring unit is disposed inside the neutralization tank, the discharge pipe is connected to the lower part of the neutralization tank, and both the pH sensor and the liquid level sensor are disposed inside the neutralization tank.

[0006] The cleaning assembly includes two filter plates, a circulation pump, a transfer unit, and multiple first nozzles. The two filter plates are both located on one side of the neutralization tank. The inlet of the circulation pump is located on one side of the filter plates. The transfer unit is located at the outlet of the circulation pump and is located inside the neutralization tank. The multiple first nozzles are sequentially arranged on the transfer unit.

[0007] The stirring unit includes a stirring component, a stirring shaft, multiple stirring plates, multiple bottom stirring rods, multiple U-shaped rods, and multiple bottom rotating plates. The stirring component is positioned above the neutralization tank. The output end of the stirring component is fixedly connected to one end of the stirring shaft. The other end of the stirring shaft passes through the neutralization tank and is located inside the neutralization tank. Multiple stirring shafts are sequentially distributed around the outer wall of the stirring shaft. Multiple bottom stirring rods are sequentially distributed at the other end of the stirring shaft. Multiple U-shaped rods are sequentially disposed on the inner bottom wall of the neutralization tank. Multiple bottom rotating plates are respectively sleeved on the outer wall of the corresponding U-shaped rods. The bottom rotating plates are rotatably connected to the U-shaped plates.

[0008] The transfer unit includes a fixed groove, a rotating groove, two sliding rings, two sealing rings, and multiple second nozzles. The rotating groove has multiple flow grooves, all of which are connected to the fixed groove. The fixed groove is fixedly connected to the neutralization tank and located on the inner wall of the neutralization tank. The rotating groove is installed inside the fixed groove and is fixedly connected to the stirring shaft, and is sleeved on the outer wall of the stirring shaft. The two sliding rings are fixedly connected to the rotating groove and are sequentially sleeved on the outer wall of the rotating groove. The two sliding rings are slidably connected to the fixed groove. The two sealing rings are fixedly connected to the fixed groove and located at the connection between the fixed groove and the rotating groove. The multiple second nozzles are connected to the rotating groove and are sequentially distributed below the rotating groove.

[0009] The cleaning assembly further includes a feeding unit, which is disposed on the neutralization tank;

[0010] The feeding unit includes a feeding bin, a feeding pump, a feeding pipe, a fixed base, and an electronic valve. The fixed base has an annular connecting groove. The stirring shaft has multiple feeding holes and feeding channels. The feeding bin is located above the neutralization tank. The feeding pump is located inside the feeding bin. The fixed base is located inside the neutralization tank. The fixed base is rotatably connected to the stirring shaft and is sleeved on the outer wall of the stirring shaft. One end of the feeding pipe is connected to the water outlet of the feeding pump. The other end of the feeding pipe passes through the feeding bin and the neutralization tank and is connected to the annular connecting groove of the fixed base. The annular connecting groove is connected to the multiple feeding holes. The feeding holes are connected to the feeding channels. The electronic valve is located inside the feeding channels.

[0011] The cleaning assembly further includes a circulation channel, a valve mechanism, and a filter plate cleaning unit. The circulation channel is connected to the neutralization tank and located on one side of the neutralization tank. The valve mechanism is located inside the circulation channel. The filter plate cleaning unit is located inside the circulation channel. The circulation pump is located at one end of the circulation channel, and the inlet of the circulation pump is connected to the circulation channel.

[0012] The valve mechanism includes a valve drive component and a ball valve. The valve drive component is located on one side of the circulation channel. The output end of the valve drive component passes through the circulation channel and is fixedly connected to the ball valve. The ball valve and the circulation channel are mutually adapted.

[0013] The filter plate cleaning unit includes a filter plate lifting component, a U-shaped plate, a sliding plate, a filter plate flipping component, a flipping shaft, two sealing gaskets, and a backwashing mechanism. The neutralization tank has a chute. The filter plate lifting component is located on one side of the neutralization tank and above the circulation channel. The output end of the filter plate lifting component is fixedly connected to the U-shaped plate. One end of the sliding plate is slidably connected to the chute, and the other end of the sliding plate is fixedly connected to the U-shaped plate. The output end of the filter plate flipping component is fixedly connected to one side of the U-shaped plate and passes through the U-shaped plate, and is fixedly connected to the flipping shaft. The flipping shaft is rotatably connected to the U-shaped plate. Two filter plates are symmetrically arranged outside the flipping shaft. The circulation channel has a slot that is compatible with the filter plates. Two sealing gaskets are respectively arranged on the corresponding filter plates, and the sealing gaskets are compatible with the slots. The backwashing mechanism is located on one side of the neutralization tank.

[0014] The backwashing mechanism includes a water tank, a backwashing pump body, a telescopic hose, a fixed pipe, a backwashing nozzle, a nozzle moving part, a baffle, and a collection box. The collection box is placed below the circulating pump, and the water tank is placed to one side of the collection box. The backwashing pump body is located inside the water tank. The two ends of the telescopic hose are respectively connected to the water outlet of the backwashing pump body and one end of the fixed pipe. The other end of the fixed pipe is connected to the backwashing nozzle. The nozzle moving part is located above the water tank, and the output end of the nozzle moving part is fixedly connected to the fixed pipe. The baffle is located above the backwashing pump body and on one side of the filter plate.

[0015] The present invention also provides a method for treating 3,3'-dichlorobenzidine hydrochloride neutralization wastewater, using the above-described 3,3'-dichlorobenzidine hydrochloride neutralization wastewater treatment system, comprising the following steps:

[0016] Neutral wastewater is pre-stored in the neutralization tank;

[0017] The strongly alkaline waste liquid generated during the preparation process of 3,3'-dichlorobenzidine hydrochloride is slowly transported into the neutralization tank;

[0018] The stirring unit is started to mix the strongly alkaline waste liquid and the neutral wastewater until the pH is maintained between 4 and 5. Then the supply of the strongly alkaline waste liquid is stopped. At this time, the environment is weakly alkaline, and organic matter begins to precipitate, undergoing polymerization or flocculation reactions, resulting in precipitates, impurities or suspended solids.

[0019] The liquid is discharged from the neutralization tank and filtered through the filter plate to remove sediment, impurities, or suspended solids.

[0020] The filtrate is transported to the transfer unit via the circulation pump.

[0021] The filtrate is sprayed from multiple first nozzles, which evenly washes away the precipitates, impurities or suspended matter attached to the inside of the neutralization tank, and then continues to flow to the filter plate for filtration, thus circulating until it is clean;

[0022] The cleaned filtrate is discharged from the neutralization tank and enters the subsequent reactor for catalytic oxidation.

[0023] This invention discloses a 3,3'-dichlorobenzidine hydrochloride neutralization wastewater treatment system and method. First, neutral wastewater is pre-stored in a neutralization tank. Then, strongly alkaline wastewater generated during the preparation of 3,3'-dichlorobenzidine hydrochloride is slowly transported into the neutralization tank. Next, the stirring unit is activated to mix the strongly alkaline wastewater and the neutral wastewater until the pH sensor detects that the pH remains between 4 and 5. At this point, the strongly alkaline wastewater is stopped, creating a weakly alkaline environment where organic matter begins to precipitate, undergoing polymerization or flocculation reactions, resulting in precipitates, impurities, or suspended solids. The liquid is discharged from the neutralization tank and filtered through a filter plate to remove precipitates, impurities, or suspended solids. The filtrate is then transported to the transfer unit via a circulation pump. Finally, the filtrate is sprayed from multiple first nozzles. The process evenly flushes away the precipitates, impurities, or suspended solids adhering to the inside of the neutralization tank, and then continues to flow to the filter plate for filtration. Finally, the cleaned filtrate is discharged from the neutralization tank and enters the subsequent reactor for catalytic oxidation. Through the above structural setup, the neutralized waste liquid is discharged and filtered, and then the filtered filtrate is returned to the neutralization tank to wash away the adhering precipitates, impurities, or suspended solids. This repeated filtration process cleans the adhering precipitates, impurities, or suspended solids, preventing accumulation that could affect the efficiency and quality of the subsequent neutralization waste liquid. Due to the improved quality of the neutralized waste liquid, the quality of the subsequent catalytic oxidation is also greatly improved. Moreover, the operation is automatic, and even after long-term use, no manual intervention is required for cleaning, significantly improving the efficiency of neutralization waste liquid treatment. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0025] Figure 1 This is a schematic diagram of the wastewater treatment system for neutralizing 3,3'-dichlorobenzidine hydrochloride according to the present invention.

[0026] Figure 2 This is a cross-sectional view of the wastewater treatment system for neutralizing 3,3'-dichlorobenzidine hydrochloride according to the present invention.

[0027] Figure 3 This is the invention Figure 2 Enlarged view of the local structure at point A.

[0028] Figure 4 This is the invention Figure 2 Enlarged view of the local structure at point B.

[0029] Figure 5 This is the invention Figure 2 Enlarged view of the local structure at point C.

[0030] Figure 6This is a diagram of the internal structure of the neutralization tank of the present invention.

[0031] Figure 7 This is a schematic diagram of the stirring unit of the present invention.

[0032] Figure 8 This is a schematic diagram of the filter plate cleaning unit of the present invention.

[0033] Figure 9 This is a flowchart of the steps of the wastewater treatment method for neutralizing 3,3'-dichlorobenzidine hydrochloride according to the present invention.

[0034] 1- Neutralization tank, 2- Discharge pipe, 3- pH sensor, 4- Liquid level sensor, 5- Filter plate, 6- Circulation pump, 7- First nozzle, 8- Stirring component, 9- Stirring shaft, 10- Stirring plate, 11- Bottom stirring rod, 12- U-shaped rod, 13- Bottom rotating plate, 14- Fixed groove, 15- Rotating groove, 16- Sliding ring, 17- Sealing ring, 18- Second nozzle, 19- Collection box, 20- Flow groove, 21- Feeding bin, 22- Feeding pump, 23- Feeding pipe, 24- Fixed base. 25-Electronic valve, 26-Annular connecting groove, 27-Feeding hole, 28-Feeding channel, 29-Circulation channel, 30-Valve drive component, 31-Ball valve, 32-Filter plate lifting component, 33-U-shaped plate, 34-Slide plate, 35-Filter plate flipping component, 36-Flipping shaft, 37-Sealing gasket, 38-Slide groove, 39-Groogging, 40-Water tank, 41-Backwash pump body, 42-Telescopic hose, 43-Fixed pipe, 44-Backwash nozzle, 45-Nozzle moving component, 46-Baffle. Detailed Implementation

[0035] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention.

[0036] Please see Figures 1 to 8This invention provides a 3,3'-dichlorobenzidine hydrochloride neutralization wastewater treatment system, comprising a neutralization tank 1, a stirring unit, a discharge pipe 2, a pH sensor 3, a liquid level sensor 4, and a cleaning assembly. The cleaning assembly includes two filter plates 5, a circulation pump 6, a transfer unit, and multiple first nozzles 7. The stirring unit includes a stirring component 8, a stirring shaft 9, multiple stirring plates 10, multiple bottom stirring rods 11, multiple U-shaped rods 12, and multiple bottom rotating plates 13. The transfer unit includes a fixed groove 14, a rotating groove 15, two sliding rings 16, two sealing rings 17, and multiple second nozzles 18. The rotating groove 15 has multiple flow grooves 20. The cleaning assembly also includes a feeding unit, which includes a feeding bin 21 and a feeding pump 2. 2. The feeding pipe 23, the fixed seat 24, and the electronic valve 25 are provided. The fixed seat 24 has an annular connecting groove 26. The stirring shaft 9 has multiple feeding holes 27 and a feeding channel 28. The cleaning assembly also includes a circulation channel 29, a valve mechanism, and a filter plate cleaning unit. The valve mechanism includes a valve driving component 30 and a ball valve 31. The filter plate cleaning unit includes a filter plate lifting component 32, a U-shaped plate 33, a sliding plate 34, a filter plate flipping component 35, a flipping shaft 36, two sealing gaskets 37, and a backwashing mechanism. The neutralization tank 1 has a chute 38. The backwashing mechanism includes a water tank 40, a backwashing pump body 41, a telescopic hose 42, a fixed pipe 43, a backwashing nozzle 44, a nozzle moving component 45, a baffle 46, and a collection box 19.

[0037] The stirring unit is located inside the neutralization tank 1, the discharge pipe 2 is connected to the bottom of the neutralization tank 1, the pH sensor 3 and the liquid level sensor 4 are both located inside the neutralization tank 1, the two filter plates 5 are both located on one side of the neutralization tank 1, the inlet of the circulation pump 6 is located on one side of the filter plate 5, the transfer unit is located at the outlet of the circulation pump 6, the transfer unit is located inside the neutralization tank 1, and a plurality of first nozzles 7 are sequentially arranged on the transfer unit.

[0038] First, neutral wastewater is pre-stored in the neutralization tank 1. Then, the strongly alkaline wastewater generated during the preparation of 3,3'-dichlorobenzidine hydrochloride is slowly transported into the neutralization tank 1. Next, the stirring unit is activated to mix the strongly alkaline wastewater and neutral wastewater until the pH sensor 3 detects that the pH remains between 4 and 5. At this point, the strongly alkaline wastewater is stopped, creating a weakly alkaline environment where organic matter begins to precipitate, undergoing polymerization or flocculation reactions, resulting in precipitates, impurities, or suspended solids. The liquid is discharged from the neutralization tank 1 and filtered through the filter plate 5 to remove precipitates, impurities, or suspended solids. The filtrate is then transported to the transfer unit via the circulation pump 6. The filtrate is sprayed from multiple first nozzles 7, uniformly flushing down the precipitates, impurities, or suspended solids adhering to the inside of the neutralization tank 1, and then continues to flow to the filter plate 5 for further filtration. Finally, the cleaned filtrate is discharged from the neutralization tank 1 and enters the subsequent reactor for catalytic oxidation.

[0039] Secondly, the stirring component 8 is disposed above the neutralization tank 1. The output end of the stirring component 8 is fixedly connected to one end of the stirring shaft 9. The other end of the stirring shaft 9 passes through the neutralization tank 1 and is located inside the neutralization tank 1. Multiple stirring shafts 9 are sequentially distributed around the outer wall of the stirring shaft 9. Multiple bottom stirring rods 11 are sequentially distributed at the other end of the stirring shaft 9. Multiple U-shaped rods 12 are sequentially disposed on the inner bottom wall of the neutralization tank 1. Multiple bottom rotating plates 13 are respectively sleeved on the outer wall of the corresponding U-shaped rods 12. The bottom rotating plates 13 are rotatably connected to the U-shaped plates 33. The stirring component 8 is a motor. When the stirring component 8 is started, it drives the stirring shaft 9 to rotate, which in turn causes the multiple stirring plates 10 and the bottom stirring rod 11 to rotate, mixing the strongly alkaline waste liquid and the neutral waste liquid to ensure a full reaction. At the same time, when the bottom stirring rod 11 rotates, it drives the bottom rotating plate 13 located on the U-shaped rod 12 to rotate, thereby relying on the bottom rotating plate 13 to further stir and mix the liquid in the bottom wall area of ​​the neutralization tank 1, greatly improving the mixing uniformity and preventing the liquid at the bottom from not being stirred and mixed.

[0040] Meanwhile, the rotating groove 15 has multiple flow grooves 20, all of which are connected to the fixed groove 14. The fixed groove 14 is fixedly connected to the neutralization tank 1 and located on the inner wall of the neutralization tank 1. The rotating groove 15 is installed inside the fixed groove 14. The rotating groove 15 is fixedly connected to the stirring shaft 9 and is sleeved on the outer wall of the stirring shaft 9. Two sliding rings 16 are fixedly connected to the rotating groove 15 and are sequentially sleeved on the outer wall of the rotating groove 15. Two sliding rings 16 are slidably connected to the fixed groove 14. Two sealing rings 17 are fixedly connected to the fixed groove 14 and located at the connection between the fixed groove 14 and the rotating groove 15. Multiple second nozzles 18 are connected to the rotating groove 15 and are sequentially distributed below the rotating groove 15. When the liquid flows back into the fixed groove 14, it can enter the rotating groove 15 through the flow groove 20. At this time, the second nozzle 18 sprays the filtrate into the neutralization tank 1 to achieve a rinsing effect. Simultaneously, when the stirring shaft 9 rotates, it drives the rotating groove 15 to rotate, which in turn drives multiple first nozzles 7 and second nozzles 18 to rotate, thereby enabling rotating spraying and significantly increasing the spray coverage area. At the same time, the first nozzles 7 can rinse the inner wall of the neutralization tank 1, and the second nozzles 18 can rinse the stirring shaft 9, the stirring rod, and the stirring rod. In addition, when the rotating groove 15 rotates, the sliding ring 16 slides inside the fixed groove 14 to maintain the stability of the rotating groove 15, and the sealing ring 17 seals the rotating connection to prevent leakage.

[0041] Additionally, the feeding unit is mounted on the neutralization tank 1; the fixed base 24 has an annular connecting groove 26, the stirring shaft 9 has multiple feeding holes 27 and a feeding channel 28, the feeding bin 21 is located above the neutralization tank 1, the feeding pump 22 is located inside the feeding bin 21, the fixed base 24 is located inside the neutralization tank 1, the fixed base 24 is rotatably connected to the stirring shaft 9 and is sleeved on the outer wall of the stirring shaft 9, one end of the feeding pipe 23 is connected to the water outlet of the feeding pump 22, the other end of the feeding pipe 23 passes through the feeding bin 21 and the neutralization tank 1, and is connected to the annular connecting groove 26 of the fixed base 24, the annular connecting groove 26 is connected to multiple feeding holes 27, the feeding holes 27 are connected to the feeding channel 28, and the electronic valve 25 is located inside the feeding channel 28. Strong alkaline waste liquid is stored in the feeding hopper 21 and then slowly pumped into the feeding pipe 23 by the feeding pump 22, flowing into the annular connecting groove 26. At this time, the strong alkaline waste liquid enters the feeding channel 28 through the feeding hole 27 and finally enters the neutralization tank 1 to mix with the neutral waste liquid, and then stirring is started. At this time, the electronic valve 25 can be closed to prevent liquid backflow. In addition, when the strong alkaline waste liquid is pumped in, the stirring shaft 9 can also be slowly rotated to mix, thereby mixing while the waste liquid is being input, which can improve the neutralization efficiency and effect.

[0042] Then, the circulation channel 29 is connected to the neutralization tank 1 and located on one side of the neutralization tank 1. The valve mechanism is located inside the circulation channel 29, the filter plate cleaning unit is located inside the circulation channel 29, and the circulation pump 6 is located at one end of the circulation channel 29, with the inlet end of the circulation pump 6 connected to the circulation channel 29. After the valve mechanism is opened, the liquid with reduced pH value can be transported into the circulation channel 29. At this time, impurities can be filtered through the filter plate 5. After filtration, the filter plate 5 is cleaned by the filter plate cleaning unit.

[0043] Furthermore, the valve drive component 30 is disposed on one side of the circulation channel 29. The output end of the valve drive component 30 passes through the circulation channel 29 and is fixedly connected to the ball valve 31. The ball valve 31 and the circulation channel 29 are mutually compatible. The valve drive component 30 is a self-locking motor. When the valve drive component 30 is activated, it drives the ball valve 31 to rotate and open, thereby allowing the liquid with reduced pH value to flow into the circulation channel 29. At the same time, the circulation pump 6 is activated, thereby accelerating the flow of liquid and transporting the filtrate after impurity filtration to the fixed tank 14.

[0044] Furthermore, the neutralization tank 1 has a chute 38, the filter plate lifting component 32 is disposed on one side of the neutralization tank 1 and located above the circulation channel 29, the output end of the filter plate lifting component 32 is fixedly connected to the U-shaped plate 33, one end of the sliding plate 34 is slidably connected to the chute 38, the other end of the sliding plate 34 is fixedly connected to the U-shaped plate 33, the output end of the filter plate flipping component 35 is fixedly connected to one side of the U-shaped plate 33, the output end of the filter plate flipping component 35 passes through the U-shaped plate 33 and is fixedly connected to the flipping shaft 36, the flipping shaft 36 is rotatably connected to the U-shaped plate 33, two filter plates 5 are symmetrically disposed outside the flipping shaft 36, the circulation channel 29 has a slot 39, the slot 39 is adapted to the filter plate 5, two sealing gaskets 37 are respectively disposed on the corresponding filter plate 5, the sealing gaskets 37 are adapted to the slot 39, and the backwashing mechanism is disposed on one side of the neutralization tank 1. The filter plate lifting component 32 is a self-locking cylinder. After filtering for a period of time, when the filter plate 5 needs to be cleaned, the circulation channel 29 is first closed by the ball valve 31. Then, the filter plate lifting component 32 is activated, driving the U-shaped plate 33 to move upward, thereby moving the filter plate 5 out of the circulation channel 29 through the slot 39. At this time, the filter plate flipping component 35 is activated, driving the flipping shaft 36 to rotate 180°, causing the two symmetrical filter plates 5 to exchange positions, thereby moving the unused filter plate 5 on top to the bottom, and the U-shaped plate 33 to the bottom, allowing the unused filter plate 5 to be reinserted into the circulation channel 29 for use. At the same time, the sealing gasket 37 matches the slot 39 to achieve a sealing effect and prevent leakage. At this time, the backwashing mechanism can be used to backwash the used filter plate 5 on top for subsequent reuse. The filter plate lifting component 32 is a self-locking cylinder. When the U-shaped plate 33 is lifted, the sliding plate 34 slides on the sliding groove 38 to maintain the stability of the lifting.

[0045] Finally, the collection box 19 is placed below the circulation pump 6, the water tank 40 is placed on one side of the collection box 19, the backwash pump body 41 is disposed inside the water tank 40, the two ends of the telescopic hose 42 are respectively connected to the water outlet of the backwash pump body 41 and one end of the fixed pipe 43, the other end of the fixed pipe 43 is connected to the backwash nozzle 44, the nozzle moving part 45 is disposed above the water tank 40, the output end of the nozzle moving part 45 is fixedly connected to the fixed pipe 43, and the baffle 46 is disposed above the backwash pump body 41 and located on one side of the filter plate 5. The water tank 40 stores cleaning water. First, the nozzle moving component 45 is activated, driving the fixed pipe 43 to move the backwash nozzle 44 to one side of the filter plate 5. At this time, the backwash pump 41 is activated, drawing out the cleaning water and spraying it from the backwash nozzle 44 to backwash the filter plate 5. The backwash water is blocked by the baffle 46 to prevent sewage from splashing and spreading to the outside. Finally, the sewage falls and is collected by the collection box 19 for subsequent centralized treatment. After the backwashing is completed, the backwash nozzle 44 is reset to make room for the filter plate 5 to flip over. The nozzle moving component 45 is a self-locking cylinder.

[0046] When using the 3,3'-dichlorobenzidine hydrochloride neutralization wastewater treatment system of this embodiment, neutral wastewater is first pre-stored in the neutralization tank 1; the strongly alkaline waste liquid generated in the preparation process of 3,3'-dichlorobenzidine hydrochloride is slowly transported into the neutralization tank 1;

[0047] Then the stirring component 8 is activated, driving the stirring shaft 9 to rotate, which in turn causes the multiple stirring plates 10 and the bottom stirring rod 11 to rotate, mixing the strongly alkaline waste liquid and the neutral waste liquid to allow them to react fully. At the same time, when the bottom stirring rod 11 rotates, it will drive the bottom rotating plate 13 located on the U-shaped rod 12 to rotate, and the bottom rotating plate 13 can further stir and mix the liquid in the bottom wall area of ​​the neutralization tank 1 until the pH sensor 3 detects that the pH is maintained between 4 and 5, and then the delivery of the strongly alkaline waste liquid is stopped.

[0048] At this point, the environment is weakly alkaline, and organic matter begins to precipitate, undergoing polymerization or flocculation reactions, resulting in precipitates, impurities, or suspended solids. The liquid is then discharged from the neutralization tank 1 and filtered through the filter plate 5 to remove precipitates, impurities, or suspended solids.

[0049] The filtrate is then pumped to the fixed tank 14 by the circulating pump 6 and enters the rotating tank 15 through the flow groove 20. At this point, the second nozzle 18 sprays the filtrate into the neutralization tank 1 for rinsing. Simultaneously, the rotation of the stirring shaft 9 drives the rotating tank 15 to rotate, which in turn drives the multiple first nozzles 7 and second nozzles 18 to rotate, thus enabling rotating spraying and significantly increasing the spray coverage area. The first nozzles 7 rinse the inner wall of the neutralization tank 1, while the second nozzles 18 rinse the stirring shaft 9, the stirring rod, and the stirring bar. The filtrate then continues to flow to the filter plate 5 for filtration, thus circulating and effectively cleaning the internal impurities. Finally, the cleaned filtrate is discharged from the neutralization tank 1 and enters the subsequent reactor for catalytic oxidation.

[0050] With the above-described structure, the neutralized waste liquid is discharged and filtered. The filtered liquid is then returned to the neutralization tank 1 to wash away any attached sediments, impurities, or suspended solids. This process is repeated to clean up any attached sediments, impurities, or suspended solids, preventing accumulation that could affect the efficiency and quality of the subsequent neutralization waste liquid. The improved quality of the neutralized waste liquid also significantly enhances the quality of the subsequent catalytic oxidation. The operation is automatic, requiring no manual intervention even after prolonged use, thus significantly improving the efficiency of neutralization waste liquid treatment.

[0051] Please see Figure 9 The present invention also provides a method for treating wastewater neutralized by 3,3'-dichlorobenzidine hydrochloride, comprising the following steps:

[0052] S1: Neutral wastewater is pre-stored in the neutralization tank 1;

[0053] S2: The strongly alkaline waste liquid generated during the preparation process of 3,3'-dichlorobenzidine hydrochloride is slowly transported into the neutralization tank 1;

[0054] S3: Start the stirring unit to mix the strongly alkaline waste liquid and the neutral wastewater until the pH is maintained between 4 and 5, then stop the supply of the strongly alkaline waste liquid. At this time, the environment is weakly alkaline, and organic matter begins to precipitate, undergoing polymerization or flocculation reactions, resulting in precipitates, impurities or suspended matter.

[0055] S4: Discharge the liquid from the neutralization tank 1 and filter out precipitates, impurities or suspended solids through the filter plate 5;

[0056] S5: The filtrate is transported to the transfer unit via the circulating pump 6;

[0057] S6: The filtrate is sprayed from multiple first nozzles 7, which evenly washes away the sediment, impurities or suspended matter attached to the inside of the neutralization tank 1, and then continues to flow to the filter plate 5 for filtration, and so on until it is clean.

[0058] S7: The cleaned filtrate is discharged from the neutralization tank 1 and enters the subsequent reactor for catalytic oxidation.

[0059] Neutral wastewater is pre-stored in the neutralization tank 1. Strongly alkaline wastewater generated during the preparation of 3,3'-dichlorobenzidine hydrochloride is slowly transported into the neutralization tank 1. The stirring unit is activated to mix the strongly alkaline wastewater and neutral wastewater until the pH is maintained between 4 and 5. Then, the transport of the strongly alkaline wastewater is stopped. At this point, in a weakly alkaline environment, organic matter begins to precipitate, undergoing polymerization or flocculation reactions, resulting in precipitates, impurities, or suspended solids. The liquid is discharged from the neutralization tank 1 and filtered through the filter plate 5 to remove precipitates, impurities, or suspended solids. The filtrate is then transported to the transfer unit via the circulation pump 6. The filtrate is sprayed from multiple first nozzles 7, uniformly flushing down the precipitates, impurities, or suspended solids adhering to the inside of the neutralization tank 1, and then continues to flow to the filter plate 5 for filtration. This cycle continues until the tank is clean. The cleaned filtrate is discharged from the neutralization tank 1 and enters a subsequent reactor for catalytic oxidation.

[0060] The above-disclosed embodiments are merely one or more preferred embodiments of this application and should not be construed as limiting the scope of this application. Those skilled in the art can understand that all or part of the processes for implementing the above embodiments and equivalent changes made in accordance with the claims of this application still fall within the scope of this application.

Claims

1. A wastewater treatment system for the neutralization of 3,3'-dichlorobenzidine hydrochloride, comprising a neutralization tank, a stirring unit, a discharge pipe, a pH sensor, and a level sensor, wherein the stirring unit is disposed inside the neutralization tank, the discharge pipe is connected to the lower part of the neutralization tank, and both the pH sensor and the level sensor are disposed inside the neutralization tank, characterized in that, It also includes cleanup components; The cleaning assembly includes two filter plates, a circulation pump, a transfer unit, and multiple first nozzles. The two filter plates are both disposed on one side of the neutralization tank. The inlet of the circulation pump is disposed on one side of the filter plates. The transfer unit is disposed on the outlet of the circulation pump and is located inside the neutralization tank. The multiple first nozzles are sequentially disposed on the transfer unit. The stirring unit includes a stirring shaft; The cleaning assembly also includes a circulation channel, a valve mechanism, and a filter plate cleaning unit. The circulation channel is connected to the neutralization tank and located on one side of the neutralization tank. The valve mechanism is located inside the circulation channel. The filter plate cleaning unit is located inside the circulation channel. The circulation pump is located at one end of the circulation channel, and the water inlet of the circulation pump is connected to the circulation channel. The transfer unit includes a fixed groove, a rotating groove, two sliding rings, two sealing rings, and multiple second nozzles. The rotating groove has multiple flow grooves, all of which are connected to the fixed groove. The fixed groove is fixedly connected to the neutralization tank and located on the inner wall of the neutralization tank. The rotating groove is installed inside the fixed groove and is fixedly connected to the stirring shaft, and is sleeved on the outer wall of the stirring shaft. The two sliding rings are fixedly connected to the rotating groove and are sequentially sleeved on the outer wall of the rotating groove. The two sliding rings are slidably connected to the fixed groove. The two sealing rings are fixedly connected to the fixed groove and located at the connection between the fixed groove and the rotating groove. The multiple second nozzles are connected to the rotating groove and are sequentially distributed below the rotating groove. The filter plate cleaning unit includes a filter plate lifting component, a U-shaped plate, a sliding plate, a filter plate flipping component, a flipping shaft, two sealing gaskets, and a backwashing mechanism. The neutralization tank has a chute. The filter plate lifting component is located on one side of the neutralization tank and above the circulation channel. The output end of the filter plate lifting component is fixedly connected to the U-shaped plate. One end of the sliding plate is slidably connected to the chute, and the other end of the sliding plate is fixedly connected to the U-shaped plate. The output end of the filter plate flipping component is fixedly connected to one side of the U-shaped plate. The output end of the filter plate flipping component passes through the U-shaped plate and is fixedly connected to the flipping shaft. The flipping shaft is rotatably connected to the U-shaped plate. Two filter plates are symmetrically arranged outside the flipping shaft. The circulation channel has a slot that is compatible with the filter plates. Two sealing gaskets are respectively arranged on the corresponding filter plates, and the sealing gaskets are compatible with the slots. The backwashing mechanism is located on one side of the neutralization tank.

2. The 3,3'-dichlorobenzidine hydrochloride neutralization wastewater treatment system as described in claim 1, characterized in that, The stirring unit further includes a stirring component, multiple stirring plates, multiple bottom stirring rods, multiple U-shaped rods, and multiple bottom rotating plates. The stirring component is disposed above the neutralization tank. The output end of the stirring component is fixedly connected to one end of the stirring shaft. The other end of the stirring shaft passes through the neutralization tank and is located inside the neutralization tank. Multiple stirring shafts are sequentially distributed around the outer wall of the stirring shaft. Multiple bottom stirring rods are sequentially distributed at the other end of the stirring shaft. Multiple U-shaped rods are sequentially disposed on the inner bottom wall of the neutralization tank. Multiple bottom rotating plates are respectively sleeved on the outer wall of the corresponding U-shaped rods. The bottom rotating plates are rotatably connected to the U-shaped plates.

3. The 3,3'-dichlorobenzidine hydrochloride neutralization wastewater treatment system as described in claim 1, characterized in that, The valve mechanism includes a valve drive component and a ball valve. The valve drive component is disposed on one side of the circulation channel. The output end of the valve drive component passes through the circulation channel and is fixedly connected to the ball valve. The ball valve and the circulation channel are mutually adapted.

4. The 3,3'-dichlorobenzidine hydrochloride neutralization wastewater treatment system as described in claim 1, characterized in that, The cleaning assembly also includes a feeding unit, which is disposed on the neutralization tank; The feeding unit includes a feeding bin, a feeding pump, a feeding pipe, a fixed base, and an electronic valve. The fixed base has an annular connecting groove. The stirring shaft has multiple feeding holes and feeding channels. The feeding bin is located above the neutralization tank. The feeding pump is located inside the feeding bin. The fixed base is located inside the neutralization tank. The fixed base is rotatably connected to the stirring shaft and is sleeved on the outer wall of the stirring shaft. One end of the feeding pipe is connected to the water outlet of the feeding pump. The other end of the feeding pipe passes through the feeding bin and the neutralization tank and is connected to the annular connecting groove of the fixed base. The annular connecting groove is connected to the multiple feeding holes. The feeding holes are connected to the feeding channels. The electronic valve is located inside the feeding channels.

5. The 3,3'-dichlorobenzidine hydrochloride neutralization wastewater treatment system as described in claim 1, characterized in that, The backwashing mechanism includes a water tank, a backwashing pump body, a telescopic hose, a fixed pipe, a backwashing nozzle, a nozzle moving part, a baffle, and a collection box. The collection box is placed below the circulating pump, and the water tank is placed to one side of the collection box. The backwashing pump body is located inside the water tank. The two ends of the telescopic hose are respectively connected to the water outlet of the backwashing pump body and one end of the fixed pipe. The other end of the fixed pipe is connected to the backwashing nozzle. The nozzle moving part is located above the water tank, and the output end of the nozzle moving part is fixedly connected to the fixed pipe. The baffle is located above the backwashing pump body and on one side of the filter plate.

6. A method for treating 3,3'-dichlorobenzidine hydrochloride neutralization wastewater, employing the 3,3'-dichlorobenzidine hydrochloride neutralization wastewater treatment system as described in claim 5, characterized in that, Includes the following steps: Neutral wastewater is pre-stored in the neutralization tank; The strongly alkaline waste liquid generated during the preparation process of 3,3'-dichlorobenzidine hydrochloride is slowly transported into the neutralization tank; The stirring unit is started to mix the strongly alkaline waste liquid and the neutral wastewater until the pH is maintained between 4 and 5. Then the supply of the strongly alkaline waste liquid is stopped. At this time, the environment is weakly alkaline, and organic matter begins to precipitate, undergoing polymerization or flocculation reactions, resulting in precipitates, impurities or suspended solids. The liquid is discharged from the neutralization tank and filtered through the filter plate to remove sediment, impurities, or suspended solids. The filtrate is transported to the transfer unit via the circulation pump. The filtrate is sprayed from multiple first nozzles, which evenly washes away the precipitates, impurities or suspended matter attached to the inside of the neutralization tank, and then continues to flow to the filter plate for filtration, thus circulating until it is clean; The cleaned filtrate is discharged from the neutralization tank and enters the subsequent reactor for catalytic oxidation.

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