Wastewater treatment device for preparing clothianidin and wastewater treatment method thereof

Abstract

The present application relates to a kind of thiamethoxam preparation wastewater treatment device and its wastewater treatment method, including reaction kettle body, the outside of the reaction kettle body is fixedly installed with jacket, liquid inlet interface and liquid outlet interface are opened in the jacket, the bottom of the jacket is fixedly installed with support leg, the top of the reaction kettle body is detachably installed with reaction kettle cover, manhole, water inlet and exhaust port are opened in the top of the reaction kettle cover, the outside of the manhole is hinged with cover, water inlet pipe is communicated in the water inlet, the bottom of the reaction kettle body is opened with drain interface, which extends to the lower portion of jacket, exhaust pipe is communicated in the exhaust port, the top of the reaction kettle body is communicated with feed pipe, the inside of the reaction kettle body is provided with stirring mechanism and detection mechanism.The present application makes the acid-base distribution in the inside of reaction kettle body more uniform, material reaction is more thorough, enhances the acid-base neutralization uniformity, improves the wastewater treatment effect.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, specifically to a wastewater treatment device and method for the preparation of thiamethoxam. Background Technology

[0002] The wastewater generated during the production of thiamethoxam has a high salt content, many solid impurities, and complex water composition, making it difficult to treat. In the entire wastewater treatment process, acid-base neutralization is the most critical pretreatment step. Whether the materials are mixed evenly and whether the reaction is sufficient directly affects the effect of subsequent wastewater treatment and the stability of equipment operation. At present, most of the industry uses ordinary stirred reactors to treat this type of wastewater, but the structure is relatively simple, the function is relatively single, and the targeting is poor.

[0003] Existing stirred reactors on the market mostly use a straight-pipe feeding method when adding alkali powder to neutralize wastewater. The added alkali flakes are prone to clumping due to moisture. Since the solid particles and crystalline impurities in the wastewater are of varying sizes, these materials tend to accumulate in fixed positions after entering the stirred reactor. They can only be passively dispersed and mixed by the subsequent stirring rod, which easily leads to uneven acid and alkali distribution inside the stirred reactor. This results in incomplete reaction of some materials, affecting the uniformity of acid and alkali neutralization and reducing the wastewater treatment effect. Improvements are needed. Therefore, a wastewater treatment device and wastewater treatment method for thiamethoxam preparation are proposed to solve the above problems. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a wastewater treatment device and method for thiamethoxam preparation. It offers advantages such as uniform feeding and solves the problems of uneven acid-base distribution within the reactor due to the use of straight-pipe feeding of alkali powder, the tendency of added caustic soda flakes to clump due to moisture, and the uneven accumulation of solid particles and crystalline impurities in the wastewater. These materials, after entering the stirred reactor, tend to accumulate in fixed positions, requiring passive mixing by subsequent stirring rods. This results in incomplete reaction of some materials, affecting the uniformity of acid-base neutralization and reducing the wastewater treatment effect.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a wastewater treatment device for thiamethoxam preparation, comprising a reaction vessel body, a jacket fixedly installed on the outside of the reaction vessel body, an inlet port and an outlet port on the jacket, a support leg fixedly installed at the bottom of the jacket, a reaction vessel cover detachably installed on the top of the reaction vessel body, a manhole, a water inlet port and an exhaust port on the top of the reaction vessel cover, a cover body hinged to the outside of the manhole, a water inlet pipe connected to the water inlet port, a drain port extending through and below the jacket at the bottom of the reaction vessel body, an exhaust pipe connected to the exhaust port, a feed pipe connected to the top of the reaction vessel body, and a stirring mechanism and a detection mechanism arranged inside the reaction vessel body.

[0006] Furthermore, annular plates are fixedly installed on the outside of the reactor body and the outside of the reactor cover, and the two annular plates are detachably connected by a first bolt.

[0007] Furthermore, the inlet port is connected to an inlet pipe, the outlet port is connected to an outlet pipe, and the drain port is connected to a drain pipe.

[0008] Furthermore, the stirring mechanism includes a transmission assembly, which is fixedly connected to the top of the reactor body. The output end of the transmission assembly is fixedly installed with a rotating shaft that penetrates and extends into the reactor body. From top to bottom, the outside of the rotating shaft is provided with a feeding assembly, a first stirring assembly, a second stirring assembly, and a scraping assembly. The feed pipe is connected to the feeding assembly.

[0009] Furthermore, the transmission assembly includes a frame, which is fixedly connected to the top of the reactor body. A motor is fixedly installed on the top of the frame, a reducer is fixedly installed at the output end of the motor, and a coupling is fixedly installed at the output end of the reducer. The output end of the coupling is fixedly connected to the top of the rotating shaft.

[0010] Furthermore, the feeding assembly includes a feeding cylinder, which is fixedly connected to the inside of the reactor lid. A dynamic seal is provided between the feeding cylinder and the rotating shaft. The feed pipe is connected to the feeding cylinder. Multiple first crushing teeth are fixedly installed inside the feeding cylinder, and all of the multiple first crushing teeth are located below the dynamic seal. Multiple second crushing teeth are fixedly installed outside the rotating shaft. The multiple first crushing teeth and the multiple second crushing teeth are multi-layered, and the multi-layered first crushing teeth and multi-layered second crushing teeth are staggered. Multiple feeding holes are opened at the bottom of the feeding cylinder, and all of the multiple feeding holes are located below the reactor lid. A guide plate is fixedly installed outside the rotating shaft. There is a gap between the bottom of the feeding cylinder and the top of the guide plate. A guide strip is fixedly installed on the top of the guide plate.

[0011] Furthermore, the first stirring assembly includes a first connecting cylinder, which is fixedly connected to the outside of the rotating shaft. A first crossbar is fixedly installed on the outside of the first connecting cylinder, and a stirring plate is fixedly installed on the side of the first crossbar away from the first connecting cylinder.

[0012] Furthermore, the second stirring assembly includes a second connecting cylinder, which is fixedly connected to the outside of the rotating shaft, and a stirring rod is fixedly installed on the outside of the second connecting cylinder.

[0013] Furthermore, the scraping assembly includes a vertical rod, which is fixedly connected to the bottom of the rotating shaft. A scraper is fixedly installed at the bottom of the vertical rod, and the scraper is in contact with the inner wall of the reactor body.

[0014] Furthermore, the detection mechanism includes a temperature sensor and a pH sensor. Two detection interfaces are provided on the top of the reactor lid. The temperature sensor and the pH sensor are detachably connected to the top of the two detection interfaces by a second bolt. The probes of the temperature sensor and the pH sensor both penetrate the reactor lid and extend into the interior of the reactor body.

[0015] Another technical problem solved by the present invention is to provide a method for treating wastewater from the preparation of thiamethoxam according to any one of the above claims, comprising the following specific steps:

[0016] S1 Acid-Base Neutralization: Pump the wastewater phase from the acid water receiving tank to the reactor body, turn on the stirring mechanism to stir the wastewater, add an appropriate amount of caustic soda flakes for each batch of wastewater, the flow meter automatically measures the addition, the temperature sensor detects whether the temperature inside the reactor body does not exceed 50℃, if the temperature is not qualified, adjust the temperature of the heat exchange medium inside the jacket, after the caustic soda flakes are added, continue stirring for 10 to 20 minutes, the pH sensor detects whether the pH value is controlled between 6 and 9, if the pH value is not qualified, add caustic soda flakes as appropriate, after neutralization is completed, collect to the transfer tank;

[0017] S2 Oil Separation and Primary Evaporation: After neutralization, the wastewater is separated into oil phases in an oil separator and then flows by gravity to the primary evaporator. The vacuum pump is turned on to control the negative pressure inside the evaporator at -0.08 to -0.09 MPa. Steam is introduced into the jacket of the evaporator and the temperature inside the evaporator is controlled at 40 to 50°C. The steam is condensed and collected in a high-nitrogen water receiving tank after passing two stages of -15°C frozen brine. The primary evaporator is sampled and tested. The ammonia nitrogen in the primary evaporator is ≤1000 mg / L. After passing the control, heating is stopped, the vacuum pump is turned off, the vacuum inside the evaporator is broken, and the material inside the evaporator is placed into the feed storage tank.

[0018] S3 Thin-film evaporation and concentration: Wastewater in the temporary storage tank is pumped to the preheater, the vacuum pump is turned on, and the negative pressure in the thin-film evaporator is controlled at -0.08 to -0.09 MPa. Low-pressure steam is introduced into the jacket of the thin-film evaporator for continuous evaporation. The steam is condensed by two stages of -15℃ frozen brine and flows by gravity to the condensate receiving tank, then flows into the intermediate condensate tank, and finally is pumped to the wastewater treatment plant. Non-condensable gas is condensed by one stage of -15℃ frozen brine and collected in the ammonia removal receiving tank. It is then combined with the initial distillate and sent to the hazardous waste storage for temporary storage. By monitoring the wastewater concentration and temperature at the thin-film outlet, the material inflow and outflow rates and the steam flow rate are adjusted to maintain the solid content of the concentrate at 30-40%. The concentrate is then sent to the crystallization kettle.

[0019] S4 Crystallization and Centrifugation: The concentrated liquid with a solid content of 30-40% flows by gravity to the crystallization kettle. The cooling brine is passed into the jacket of the crystallization kettle to lower the temperature of the material to 5-10°C. After keeping it at this temperature for 1 hour, the material is discharged into the centrifuge. The centrifugal mother liquor is collected into the centrifugal mother liquor tank and then pumped to the mother liquor dryer for processing. The solid salt residue is loaded into a clean container to obtain sodium chloride as a by-product.

[0020] S5 Mother Liquor Drying: Centrifuged mother liquor that cannot be reused due to excessive impurities is sent to a scraped evaporator for dehydration, with the temperature controlled at 100.0~115.0℃. The dehydrated solid waste is then temporarily stored in a hazardous waste storage facility.

[0021] Compared with the prior art, the technical solution of this application has the following beneficial effects:

[0022] The wastewater treatment device and method for thiamethoxam preparation are designed with a feed pipe, a transmission assembly, a rotating shaft, and a feeding assembly. When the transmission assembly drives the rotating shaft and the feeding assembly to rotate, the caustic soda flakes enter the interior of the feeding assembly through the feed pipe. The rotating shaft and the feeding assembly work together to not only crush the caustic soda flakes but also feed the crushed caustic soda powder in a 360° ring, distributing the caustic soda powder in various areas. This makes the acid-base distribution inside the reactor more uniform and improves the feeding effect.

[0023] The wastewater treatment device and method for thiamethoxam preparation, by setting up a transmission component, a rotating shaft, a first stirring component and a second stirring component, when the transmission component drives the rotating shaft, the first stirring component and the second stirring component to rotate, the first stirring component and the second stirring component stir the alkali powder, so that the material reaction is more thorough, the acid-base neutralization uniformity is enhanced, and the wastewater treatment effect is improved;

[0024] The wastewater treatment device and method for thiamethoxam preparation, by setting up a transmission component, a rotating shaft and a scraping component, when the transmission component drives the rotating shaft and the scraping component to rotate, the scraping component cleans the crystallized precipitate inside the reaction vessel, reducing the difficulty of maintenance;

[0025] The wastewater treatment device and method for thiamethoxam preparation include a detection mechanism that can monitor the temperature and pH of the wastewater, facilitating better control of temperature and pH and improving the stability of acid-base neutralization. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0027] Figure 2 This is a partial structural diagram of the present invention;

[0028] Figure 3 This is a partial structural diagram of the stirring mechanism of the present invention;

[0029] Figure 4 For the present invention Figure 3 Enlarged view of point A in the middle;

[0030] Figure 5 This is a partial cross-sectional view of the feeding assembly of the present invention;

[0031] Figure 6 For the present invention Figure 5 Enlarged view at point B in the middle;

[0032] Figure 7 This is a partial structural diagram of the feeding component of the present invention;

[0033] Figure 8 For the present invention Figure 7 Enlarged view at point C;

[0034] Figure 9 This is a schematic diagram of the feeding cylinder structure of the present invention.

[0035] In the diagram: 1. Reactor body; 2. Jacket; 3. Support leg; 4. Reactor cover; 5. Water inlet pipe; 6. Exhaust pipe; 7. Feed pipe; 8. Stirring mechanism; 81. Transmission assembly; 82. Rotating shaft; 83. Feeding assembly; 831. Feeding cylinder; 832. First crushing tooth; 833. Second crushing tooth; 834. Guide plate; 835. Guide strip; 84. First stirring assembly; 85. Second stirring assembly; 86. Scraping assembly; 9. Detection mechanism. Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] Please see Figure 1This embodiment of a wastewater treatment device for thiamethoxam preparation includes a reactor body 1. A jacket 2 is fixedly installed on the outside of the reactor body 1 for introducing a heat exchange medium to heat or cool the wastewater inside the reactor body 1. The jacket 2 has an inlet and an outlet for circulating the heat exchange medium. Four support legs 3 are fixedly installed at the bottom of the jacket 2. A reactor cover 4 is detachably installed on the top of the reactor body 1. The top of the reactor cover 4 has a manhole, a water inlet, and an exhaust outlet. A cover is hinged to the outside of the manhole. During normal operation, the cover is closed and sealed. During maintenance, it can be quickly opened to facilitate manual entry into the interior of the reactor body 1. For maintenance, the inlet port is connected to an inlet pipe 5 for wastewater to enter or for rinsing with clean water. The bottom of the reactor body 1 has a drain port that extends through and to the bottom of the jacket 2 for discharging wastewater after the acid-base neutralization treatment is completed. The exhaust port is connected to an exhaust pipe 6 for timely discharge of the gas generated by the reaction inside the reactor body 1 to ensure stable gas pressure inside the reactor body 1. The top of the reactor body 1 is connected to a feed pipe 7 for adding caustic soda flakes into the reactor body 1. The reactor body 1 is equipped with a stirring mechanism 8 and a detection mechanism 9 for real-time monitoring of the reaction parameters inside the reactor body 1 to ensure stable acid-base neutralization reaction.

[0038] Specifically, wastewater enters the interior of reactor body 1 through inlet pipe 5, the heat exchange medium inside jacket 2 heats reactor body 1, caustic soda flakes enter the interior through feed pipe 7, stirring mechanism 8 stirs caustic soda flakes, caustic soda flakes neutralize acid and alkali in wastewater, detection mechanism 9 detects reaction parameters inside reactor body 1, and gas generated by the reaction inside reactor body 1 is discharged from inside exhaust pipe 6 to ensure stable internal gas pressure of reactor body 1.

[0039] Please see Figure 1 In this embodiment, annular plates are fixedly installed on the outside of the reactor body 1 and the outside of the reactor cover 4, and the two annular plates are detachably connected by a first bolt.

[0040] Specifically, the two annular plates can be quickly assembled and disassembled using the first bolt, which not only provides a good sealing effect but also facilitates subsequent internal inspection, parts replacement, and cleaning maintenance of the equipment.

[0041] Please see Figure 1 In this embodiment, the inlet port is connected to an inlet pipe, the outlet port is connected to an outlet pipe, and the drain port is connected to a drain pipe.

[0042] Specifically, the heat exchange medium circulates inside the jacket 2 through the inlet and outlet pipes, and the wastewater after the acid-base reaction is discharged from the inside of the reactor body 1 through the drain pipe.

[0043] Please see Figure 2-8In this embodiment, the stirring mechanism 8 includes a transmission assembly 81, which is fixedly connected to the top of the reactor body 1. The output end of the transmission assembly 81 is fixedly installed with a rotating shaft 82 that penetrates through and extends into the reactor body 1. The outside of the rotating shaft 82 is provided with a feeding assembly 83, a first stirring assembly 84, a second stirring assembly 85 and a scraping assembly 86 arranged sequentially from top to bottom. The feed pipe 7 is connected to the feeding assembly 83.

[0044] Specifically, the transmission assembly 81 is activated, which drives the feeding assembly 83, the first stirring assembly 84, the second stirring assembly 85, and the scraping assembly 86 to rotate. The caustic soda flakes enter the interior of the feeding assembly 83 through the feed pipe 7. The feeding assembly 83 not only crushes the caustic soda flakes but also feeds the crushed caustic soda powder in a 360° ring, distributing the caustic soda powder in various areas. The first stirring assembly 84 and the second stirring assembly 85 stir the caustic soda powder, and the scraping assembly 86 cleans the crystallized precipitates inside the reactor body 1.

[0045] Please see Figure 2 In this embodiment, the transmission assembly 81 includes a frame, which is fixedly connected to the top of the reactor body 1. A motor is fixedly installed on the top of the frame, and a reducer is fixedly installed at the output end of the motor. The reducer can reduce the speed and increase the transmission torque to avoid excessive load causing equipment jamming. A coupling is fixedly installed at the output end of the reducer, and the output end of the coupling is fixedly connected to the top of the rotating shaft 82.

[0046] Specifically, by turning on the motor, the motor drives the reducer to rotate, the reducer drives the coupling to rotate, and the coupling drives the rotating shaft 82 to rotate, thereby reducing the vibration and noise of the equipment during operation.

[0047] Please see Figure 3-9 In this embodiment, the feeding assembly 83 includes a feeding cylinder 831, which is fixedly connected to the inside of the reactor cover 4. A dynamic seal is provided between the feeding cylinder 831 and the rotating shaft 82. The feed pipe 7 is connected to the feeding cylinder 831. A plurality of first crushing teeth 832 are fixedly installed inside the feeding cylinder 831, and the plurality of first crushing teeth 832 are all located below the dynamic seal. A plurality of second crushing teeth 833 are fixedly installed outside the rotating shaft 82. The plurality of first crushing teeth 832 and the plurality of second crushing teeth 833 are multi-layered. The multi-layered second crushing teeth 833 are staggered, and each layer is evenly and equidistantly distributed in a ring. The bottom of the feeding cylinder 831 is provided with multiple feeding holes, all of which are located below the reactor cover 4. The feeding holes are evenly and equidistantly distributed in a ring. A guide plate 834 is fixedly installed on the outside of the rotating shaft 82. The top of the guide plate 834 is inclined. There is a gap between the bottom of the feeding cylinder 831 and the top of the guide plate 834. Multiple guide strips 835 are fixedly installed on the top of the guide plate 834. The multiple guide strips 835 are evenly and equidistantly distributed in a ring.

[0048] Specifically, caustic soda flakes enter the feed cylinder 831 through the feed pipe 7. During the rotation of the rotating shaft 82, multiple second crushing teeth 833 are driven to rotate. Multiple first crushing teeth 832 and multiple second crushing teeth 833 crush the caustic soda flakes. The crushed caustic soda powder falls onto the inclined surface of the guide plate 834 and is located between two adjacent guide bars 835. It passes through the feed hole for 360° uniform feeding, which not only increases the contact area between the caustic soda powder and the wastewater, but also makes the acid and alkali distribution inside the reactor body 1 more uniform. During the rotation of the multiple guide bars 835, the caustic soda powder at the bottom of the feed cylinder 831 is scraped to reduce the occurrence of blockage.

[0049] Please see Figure 3 , 5 Alternatively, in this embodiment, the first stirring assembly 84 includes a plurality of first connecting cylinders, all of which are fixedly connected to the outside of the rotating shaft 82. The plurality of first connecting cylinders are evenly and equidistantly distributed in a longitudinal straight line. A plurality of first crossbars are fixedly installed on the outside of the first connecting cylinders. The plurality of first crossbars are evenly and equidistantly distributed in a ring. A stirring plate is fixedly installed on the side of the plurality of first crossbars away from the first connecting cylinders.

[0050] Specifically, during the rotation of the rotating shaft 82, multiple first connecting cylinders, multiple first crossbars and multiple stirring plates are driven to rotate, and the multiple stirring plates stir the alkali powder.

[0051] Please see Figure 3 , 5 Alternatively, in this embodiment, the second stirring assembly 85 includes a plurality of second connecting cylinders, all of which are fixedly connected to the outside of the rotating shaft 82. The plurality of second connecting cylinders are evenly and equidistantly distributed in a longitudinal straight line. A plurality of stirring rods are fixedly installed on the outside of the plurality of second connecting cylinders, and the plurality of stirring rods are evenly and equidistantly distributed in a ring.

[0052] Specifically, during the rotation of the rotating shaft 82, multiple second connecting cylinders and multiple stirring rods are driven to rotate, and the multiple stirring rods stir the alkali powder.

[0053] Please see Figure 3 , 5 Alternatively, in this embodiment, the scraping assembly 86 includes a vertical rod, which is fixedly connected to the bottom of the rotating shaft 82. A scraper is fixedly installed at the bottom of the vertical rod, and the scraper is in contact with the inner wall of the reactor body 1. The upper part of the scraper is rectangular, and the lower part is arc-shaped.

[0054] Specifically, the rotating shaft 82 drives the scraper to rotate during the rotation process, and the scraper cleans the inner side wall and inner bottom wall of the reactor body 1.

[0055] Please see Figure 1-2In this embodiment, the detection mechanism 9 includes a temperature sensor and a pH sensor. Two detection interfaces are provided on the top of the reactor cover 4. The temperature sensor and the pH sensor are detachably connected to the top of the two detection interfaces by the second bolts. The probes of the temperature sensor and the pH sensor both penetrate the reactor cover 4 and extend into the interior of the reactor body 1.

[0056] Specifically, the temperature sensor detects the temperature of the wastewater, and the pH sensor detects the pH value of the wastewater.

[0057] A method for treating wastewater from the preparation of thiamethoxam includes the following specific steps:

[0058] S1 Acid-Base Neutralization: The wastewater phase in the acid water receiving tank is pumped to the reactor body 1. The stirring mechanism 8 is turned on to stir the wastewater. An appropriate amount of caustic soda flakes is added to each batch of wastewater. The flow meter automatically measures the addition. The temperature sensor detects whether the temperature inside the reactor body 1 does not exceed 50℃. If the temperature is not up to standard, the temperature of the heat exchange medium inside the jacket 2 is adjusted. After the caustic soda flakes are added, stirring continues for 10 to 20 minutes. The pH sensor detects whether the pH value is controlled between 6 and 9. If the pH value is not up to standard, caustic soda flakes are added appropriately. After neutralization is completed, the mixture is collected in the transfer tank.

[0059] S2 Oil Separation and Primary Evaporation: After neutralization, the wastewater is separated into oil phases in an oil separator and then flows by gravity to the primary evaporator. The vacuum pump is turned on to control the negative pressure inside the evaporator at -0.08 to -0.09 MPa. Steam is introduced into the jacket of the evaporator and the temperature inside the evaporator is controlled at 40 to 50°C. The steam is condensed and collected in a high-nitrogen water receiving tank after passing two stages of -15°C frozen brine. The primary evaporator is sampled and tested. The ammonia nitrogen in the primary evaporator is ≤1000 mg / L. After passing the control, heating is stopped, the vacuum pump is turned off, the vacuum inside the evaporator is broken, and the material inside the evaporator is placed into the feed storage tank.

[0060] S3 Thin-film evaporation and concentration: Wastewater in the temporary storage tank is pumped to the preheater, the vacuum pump is turned on, and the negative pressure in the thin-film evaporator is controlled at -0.08 to -0.09 MPa. Low-pressure steam is introduced into the jacket of the thin-film evaporator for continuous evaporation. The steam is condensed by two stages of -15℃ frozen brine and flows by gravity to the condensate receiving tank, then flows into the intermediate condensate tank, and finally is pumped to the wastewater treatment plant. Non-condensable gas is condensed by one stage of -15℃ frozen brine and collected in the ammonia removal receiving tank. It is then combined with the initial distillate and sent to the hazardous waste storage for temporary storage. By monitoring the wastewater concentration and temperature at the thin-film outlet, the material inflow and outflow rates and the steam flow rate are adjusted to maintain the solid content of the concentrate at 30-40%. The concentrate is then sent to the crystallization kettle.

[0061] S4 Crystallization and Centrifugation: The concentrated liquid with a solid content of 30-40% flows by gravity to the crystallization kettle. The cooling brine is passed into the jacket of the crystallization kettle to lower the temperature of the material to 5-10°C. After keeping it at this temperature for 1 hour, the material is discharged into the centrifuge. The centrifugal mother liquor is collected into the centrifugal mother liquor tank and then pumped to the mother liquor dryer for processing. The solid salt residue is loaded into a clean container to obtain sodium chloride as a by-product.

[0062] S5 Mother Liquor Drying: Centrifuged mother liquor that cannot be reused due to excessive impurities is sent to a scraped evaporator for dehydration, with the temperature controlled at 100.0~115.0℃. The dehydrated solid waste is then temporarily stored in a hazardous waste storage facility.

[0063] The working principle of the above embodiments is as follows:

[0064] Wastewater enters the reactor body 1 through the inlet pipe 5. The heat exchange medium circulates inside the jacket 2 through the inlet and outlet pipes, heating the reactor body 1. Soda ash flakes enter the feed cylinder 831 through the feed pipe 7. During rotation, the rotating shaft 82 drives multiple second crushing teeth 833 to rotate, crushing the soda ash flakes. The crushed soda powder falls onto the inclined surface of the guide plate 834, positioned between adjacent guide strips 835, and passes through the feed hole for 360° uniform feeding. This not only increases the contact area between the soda powder and wastewater but also makes the acid-base distribution inside the reactor body 1 more uniform. During rotation, the guide strips 835 scrape the soda powder at the bottom of the feed cylinder 831, reducing clogging. During rotation, shaft 82 drives multiple first connecting cylinders, multiple first crossbars, multiple stirring plates, multiple second connecting cylinders, and multiple stirring rods to rotate. The stirring plates and rods stir the alkali powder, making the material reaction more thorough, enhancing the uniformity of acid-base neutralization, and improving the wastewater treatment effect. During rotation, shaft 82 drives the scraper to rotate, which cleans the crystallized precipitates on the inner side wall and bottom wall of the reactor body 1, reducing maintenance difficulty. Temperature sensor detects the temperature of the wastewater, and pH sensor detects the pH value of the wastewater, which facilitates better control of temperature and pH value and improves the stability of acid-base neutralization. The gas generated by the reaction inside the reactor body 1 is discharged from the inside of the exhaust pipe 6 to ensure stable internal gas pressure in the reactor body 1. The wastewater after the acid-base reaction is discharged from the inside of the reactor body 1 through the drain pipe.

[0065] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0066] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A wastewater treatment device for thiamethoxam preparation, comprising a reactor body (1), a jacket (2) fixedly installed on the outside of the reactor body (1), an inlet port and an outlet port provided on the jacket (2), a support leg (3) fixedly installed on the bottom of the jacket (2), a reactor cover (4) detachably installed on the top of the reactor body (1), a manhole, a water inlet port and an exhaust port provided on the top of the reactor cover (4), a cover body hinged to the outside of the manhole, a water inlet pipe (5) connected to the water inlet port, a drain port extending through and to the bottom of the jacket (2) provided on the bottom of the reactor body (1), an exhaust pipe (6) connected to the exhaust port, and a feed pipe (7) connected to the top of the reactor body (1), characterized in that, The reactor body (1) is equipped with a stirring mechanism (8) and a detection mechanism (9). The stirring mechanism (8) includes a transmission assembly (81), which is fixedly connected to the top of the reactor body (1). The output end of the transmission assembly (81) is fixedly installed with a rotating shaft (82) that penetrates and extends into the reactor body (1). The outside of the rotating shaft (82) is arranged from top to bottom as a feeding assembly (83), a first stirring assembly (84), a second stirring assembly (85), and a scraping assembly (86). The feed pipe (7) is connected to the feeding assembly (83).

2. The wastewater treatment device for thiamethoxam preparation according to claim 1, characterized in that, Annular plates are fixedly installed on the outside of the reactor body (1) and the outside of the reactor cover (4), and the two annular plates are detachably connected by a first bolt.

3. The wastewater treatment device for thiamethoxam preparation according to claim 1, characterized in that, The inlet port is connected to an inlet pipe, the outlet port is connected to an outlet pipe, and the drain port is connected to a drain pipe.

4. The wastewater treatment device for thiamethoxam preparation according to claim 1, characterized in that, The transmission assembly (81) includes a frame, which is fixedly connected to the top of the reactor body (1). A motor is fixedly installed on the top of the frame. A speed reducer is fixedly installed at the output end of the motor. A coupling is fixedly installed at the output end of the speed reducer. The output end of the coupling is fixedly connected to the top of the rotating shaft (82).

5. The wastewater treatment device for thiamethoxam preparation according to claim 1, characterized in that, The feeding assembly (83) includes a feeding cylinder (831), which is fixedly connected to the inside of the reactor lid (4). A dynamic seal is provided between the feeding cylinder (831) and the rotating shaft (82). The feed pipe (7) is connected to the feeding cylinder (831). A plurality of first crushing teeth (832) are fixedly installed inside the feeding cylinder (831). The plurality of first crushing teeth (832) are all located below the dynamic seal. A plurality of second crushing teeth (833) are fixedly installed outside the rotating shaft (82). The crushing teeth (832) and multiple second crushing teeth (833) are multi-layered. The multi-layered first crushing teeth (832) and the multi-layered second crushing teeth (833) are staggered. The bottom of the feeding cylinder (831) is provided with multiple feeding holes, which are located below the reactor cover (4). A guide plate (834) is fixedly installed on the outside of the rotating shaft (82). There is a gap between the bottom of the feeding cylinder (831) and the top of the guide plate (834). A guide strip (835) is fixedly installed on the top of the guide plate (834).

6. The wastewater treatment apparatus for thiamethoxam preparation according to claim 1, characterized in that, The first stirring assembly (84) includes a first connecting cylinder, which is fixedly connected to the outside of the rotating shaft (82). A first crossbar is fixedly installed on the outside of the first connecting cylinder, and a stirring plate is fixedly installed on the side of the first crossbar away from the first connecting cylinder.

7. The wastewater treatment device for thiamethoxam preparation according to claim 1, characterized in that, The second stirring assembly (85) includes a second connecting cylinder, which is fixedly connected to the outside of the rotating shaft (82), and a stirring rod is fixedly installed on the outside of the second connecting cylinder.

8. The wastewater treatment apparatus for thiamethoxam preparation according to claim 1, characterized in that, The scraping assembly (86) includes a vertical rod, which is fixedly connected to the bottom of the rotating shaft (82). A scraper is fixedly installed at the bottom of the vertical rod, and the scraper is in contact with the inner wall of the reactor body (1).

9. The wastewater treatment device for thiamethoxam preparation according to claim 1, characterized in that, The detection mechanism (9) includes a temperature sensor and a pH sensor. The top of the reactor cover (4) has two detection interfaces. The temperature sensor and the pH sensor are detachably connected to the top of the two detection interfaces by a second bolt. The probes of the temperature sensor and the pH sensor both penetrate the reactor cover (4) and extend into the reactor body (1).

10. A method for treating wastewater from the preparation of thiamethoxam according to any one of claims 1 to 9, characterized in that, The specific steps include the following: S1, acid-base neutralization: pump the wastewater phase in the acid water receiving tank to the reactor body (1), turn on the stirring mechanism (8) to stir the wastewater, add an appropriate amount of caustic soda for each batch of wastewater, the flow meter automatically measures the addition, the temperature sensor detects whether the temperature inside the reactor body (1) does not exceed 50℃, if the temperature is not qualified, adjust the temperature of the heat exchange medium inside the jacket (2), after the caustic soda is added, continue stirring for 10 to 20 minutes, the pH sensor detects whether the pH value is controlled at 6 to 9, if the pH value is not qualified, add caustic soda appropriately, after neutralization is completed, collect to the transfer tank; S2. Oil separation and primary evaporation: After neutralization, the wastewater is separated into oil phases in the oil separator and then flows by gravity to the primary evaporator. The vacuum pump is turned on to control the negative pressure inside the evaporator at -0.08 to -0.09 MPa. Steam is introduced into the jacket of the evaporator and the temperature inside the evaporator is controlled at 40 to 50°C. The steam is condensed and collected in a high-nitrogen water receiving tank after passing two stages of -15°C frozen brine. The primary evaporator is sampled and tested. The ammonia nitrogen in the primary evaporator is ≤1000 mg / L. After passing the control, heating is stopped, the vacuum pump is turned off, the vacuum inside the evaporator is broken, and the material inside the evaporator is placed into the feed storage tank. S3. Thin-film evaporation and concentration: The wastewater in the temporary storage tank is pumped to the preheater, the vacuum pump is turned on, and the negative pressure in the thin-film evaporator is controlled at -0.08 to -0.09 MPa. Low-pressure steam is introduced into the jacket of the thin-film evaporator for continuous evaporation. The steam is condensed by two stages of -15℃ frozen brine and flows by gravity to the condensate receiving tank, then flows into the intermediate condensate tank, and finally is pumped to the wastewater treatment plant. The non-condensable gas is condensed by one stage of -15℃ frozen brine and collected in the ammonia removal receiving tank. It is then combined with the initial distillate and sent to the hazardous waste storage for temporary storage. By monitoring the wastewater concentration and temperature at the thin-film outlet, the material inflow and outflow rates and the steam flow rate are adjusted to maintain the solid content of the concentrate at 30-40%. The concentrate is then sent to the crystallization kettle. S4. Crystallization and centrifugation: The concentrated liquid with a solid content of 30-40% flows by gravity to the crystallization kettle. The jacket of the crystallization kettle is circulated with chilled brine to lower the temperature of the material to 5-10°C. After keeping it at this temperature for 1 hour, the material is discharged into the centrifuge. The centrifugal mother liquor is collected into the centrifugal mother liquor tank and then pumped to the mother liquor dryer for processing. The solid salt residue is loaded into a clean container to obtain sodium chloride as a by-product. S5. Mother liquor drying: Centrifuged mother liquor that cannot be reused due to excessive impurities is sent to a scraped evaporator for dehydration, with the temperature controlled at 100.0~115.0℃. The dehydrated solid waste is then sent to a hazardous waste temporary storage facility.

Images