Device and method for treating wastewater generated in production of N-ethylpiperazine

Abstract

The invention discloses a device and a method for treating wastewater generated in production of N-ethylpiperazine, and relates to the technical field of multi-stage wastewater treatment. Comprising a pH adjusting box and an air stripping tower which are arranged in sequence, and the pH adjusting box is used for adjusting the pH of wastewater to enable the pH of the wastewater entering the air stripping tower to reach an air stripping value; the air stripping tower comprises: a tower body; the packed bed is positioned in the tower body, the packed bed comprises a fixed bed which is static relative to the tower body and at least one movable bed which is positioned above the fixed bed, and the packing is accommodated on the upper surfaces of the fixed bed and the movable bed, so that a state that the packing is arranged in a layered manner by a single packed bed is formed; a detector; according to the wastewater treatment device and method for N-ethylpiperazine production, the detector, the layered filler and the lifting mechanism are arranged, so that the device can detect the flooding phenomenon, the flooding problem can be rapidly solved, and the situation that equipment cannot continuously work due to flooding is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of multi-stage wastewater treatment, and specifically to a wastewater treatment device and method for the production of N-ethylpiperazine. Background Art

[0002] When producing N-ethylpiperazine, a large amount of wastewater will be generated. The general treatment process is: regulating tank → neutralization / coagulation → anaerobic reactor → aerobic MBR → Fenton oxidation → nanofiltration → activated carbon adsorption.

[0003] However, in actual production, it should also be combined with its water quality characteristics, such as high nitrogen content, organic pollutants, possible alkaline or solvent residues, etc. For the high-ammonia-nitrogen wastewater generated during the production of N-ethylpiperazine, it is best to add a stripping tower (stripping ammonia gas when pH>10).

[0004] Ammonia-nitrogen stripping reaction (requires alkaline conditions): NH4+ + OH - →NH3↑+H2O NH4+ + OH - →NH3↑+H2O. The ammonia gas (NH3) is carried away by the air, and the ammonia-nitrogen concentration in the remaining water is significantly reduced.

[0005] Generally, a stripping tower needs to use packing to increase the contact time and contact area between the gas phase and the liquid phase, so as to ensure the cleanliness of wastewater treatment. The packing can be divided into high-density packing and low-density packing.

[0006] For high-density packing, its high specific surface area and porosity can provide a larger gas-liquid contact area and significantly improve the mass transfer efficiency. Such as small-sized packing balls and Pall rings. However, high-density packing will increase the resistance of gas passing through, resulting in an increase in pressure drop and possibly causing flooding (such as a decrease in flooding gas velocity). Summary of the Invention

[0007] Aiming at the deficiencies of the prior art, the present invention provides a wastewater treatment device and method for the production of N-ethylpiperazine, which solves the problem that high-density packing in the prior art will increase the resistance of gas passing through, resulting in an increase in pressure drop and possibly causing flooding.

[0008] To achieve the above objectives, the present invention is realized through the following technical solutions: A wastewater treatment device for the production of N-ethylpiperazine, including a pH adjustment tank and a stripping tower arranged in sequence. The pH adjustment tank is used to adjust the pH of the wastewater so that the pH of the wastewater entering the stripping tower reaches the stripping value; Among them, the stripping tower includes: Tower body; Packing bed, the packing bed is located in the tower body, and the packing bed includes a fixed bed that is relatively stationary with the tower body and at least one moving bed located above the fixed bed. The packing is placed on the upper surfaces of the fixed bed and the moving bed, forming a state where the packing is arranged in layers in a single packing bed; A detector, which is located on the inner wall of the tower body, and the position of the detector is higher than the uppermost movable bed of the packing bed, and is used to detect whether the phenomenon of flooding occurs; A lifting mechanism, which is arranged on the tower body and is used to lift the movable bed, expand the axial clearance of the packing, reduce the pressure drop of the packing, and enable the flooded liquid to flow downward through the packing.

[0009] Further, each packing bed includes two movable beds arranged side by side up and down, and the lifting mechanism includes a lifting rod, and the action of the lifting rod can change the distance between the two movable beds relative to the fixed bed.

[0010] Further, the lower end of the lifting rod is rotatably assembled at the center of the movable bed; The movable bed includes a central sphere concentric with the tower body, a through hole is opened at the center of the central sphere, a slider is arranged in the through hole, and a spiral groove adapted to the slider is arranged on the lifting rod; The spiral height of the spiral groove above the same lifting rod is greater than the spiral height of the spiral groove below; The rotation of the lifting rod can drive the two movable beds to move axially along the tower body through the spiral groove and the slider.

[0011] Further, the lower end of the lifting rod is fixed on the lower central sphere, the upper end of the lifting rod passes through the upper central sphere and can slide relative to the upper central sphere, a top plate is fixedly arranged at the upper end of the lifting rod, and a height is reserved between the top plate and the upper central sphere; After the upper central sphere is lifted to the height of the top plate, the lower central sphere can be lifted through the lifting rod.

[0012] Further, the lifting mechanism further includes an I-beam, the I-beam is fixedly arranged above the tower body, and the I-beam is located above the packing bed. Springs are arranged between the I-beam and the upper central sphere, and springs are arranged between the upper central sphere and the lower central sphere.

[0013] Further, the lifting mechanism further includes a driving shaft, the driving shaft is located above the packing bed and is arranged along the diameter direction of the tower body. A reel is arranged in the area of the driving shaft opposite to the central sphere, and a lifting rope is connected between the reel and the upper central sphere. The rotation of the driving shaft can wind or unwind the lifting rope by the reel.

[0014] Further, the movable bed further includes: Spokes, which are radially rotatably installed on the central sphere through pin shafts, and torsion springs are arranged between the pin shafts and the central sphere; A mesh bed plate, which is of a fan-shaped structure, the mesh bed plate is located between two spokes, and one side of the mesh bed plate is fixedly connected to an adjacent spoke; On the inner wall of the tower body, there are ridges at the positions corresponding to the rising section of the moving bed. When the moving bed moves along the axial direction of the tower body, the resistance from the ridges can cause vibration, so as to adjust the gap of the packing along the radial direction of the tower body.

[0015] Furthermore, a water distributor is provided above the packing bed. The height of the water distributor is greater than that of the detector and greater than the rising height of the moving bed. A drain port is provided below one side of the tower body.

[0016] Furthermore, an air inlet is provided below one side of the tower body away from the drain port, a water eliminator is provided at the upper end inside the tower body, and an exhaust port is provided above the water eliminator.

[0017] On the other hand, the present invention also provides a wastewater treatment method for N-ethylpiperazine production, which uses the above-mentioned wastewater treatment device for N-ethylpiperazine production, including the following steps: Step 1: Add alkali to the wastewater in the pH adjustment tank to make the pH of the wastewater > 10. Step 2: Feed the alkalized wastewater into the above-mentioned stripping tower for stripping to remove NH3 in the wastewater. Step 3: Feed the liquid obtained in Step 2 into the pH neutralization tank, sedimentation tank and biological treatment tower in sequence, and finally drain the water.

[0018] The present invention has the following beneficial effects: (1) For the wastewater treatment device and method for N-ethylpiperazine production, by setting a detector, layered packing and a lifting mechanism, the device can detect the occurrence of flooding phenomenon and can quickly solve the flooding problem, avoiding the situation that the equipment cannot work continuously caused by flooding.

[0019] (2) For the wastewater treatment device and method for N-ethylpiperazine production, the packing can vibrate when moving axially, and the gap of the packing along the radial direction of the tower body is adjusted, avoiding the subsequent continuous flooding situation.

[0020] Of course, it is not necessary for any product implementing the present invention to achieve all the above-mentioned advantages simultaneously. Description of the Drawings

[0021] Figure 1 is a schematic structural diagram of the present invention; Figure 2 is a schematic internal structure diagram of the stripping tower of the present invention; Figure 3 is of the present invention Figure 2 front projection view; Figure 4 is an assembly drawing of the lifting mechanism and the packing bed of the present invention; Figure 5 is of the present inventionFigure 4 Exploded view; Figure 6 This is the exploded view of the movable bed of the present invention; Figure 7 This is the present invention Figure 6 Enlarged view of Area A; Figure 8 This is the state diagram of the packing pressing the movable bed into an umbrella-shaped structure in the present invention; Figure 9 This is the schematic diagram of the position of the convex ridge in the present invention; Figure 10 This is another perspective view of the stripping tower in Embodiment 1 of the present invention; Figure 11 This is the present invention Figure 10 Schematic diagram of the exposed driving structure; Figure 12 This is the assembly drawing of the lifting mechanism and the packing bed in Embodiment 2 of the present invention; Figure 13 This is the present invention Figure 12 Enlarged view of Area B; Figure 14 This is the present invention Figure 12 Partial orthographic projection view.

[0022] In the figure, 100, pH adjustment tank; 1, circulation buffer tank; 11, waste water inlet; 12, purified water outlet; 2, circulation pump; 3, convex ridge; 4, tower body; 41, air inlet; 42, manhole; 43, exhaust port; 44, conical head; 45, external joint; 46, drain port; 5, packing bed; 51, fixed bed; 52, movable bed; 521, mesh bed plate; 522, spoke; 523, center ball; 524, slider; 525, assembly groove; 526, pin shaft; 527, assembly head; 6, liquid level sensor; 7, lifting mechanism; 71, driving structure; 72, lifting rod; 721, spiral groove; 722, straight groove; 723, top plate; 73, driving shaft; 74, driving bevel gear; 75, driven bevel gear; 76, winding wheel; 77, spring; 78, I-beam; 79, lifting rope; 8, water distributor; 81, main pipe; 82, primary branch pipe; 83, secondary branch pipe; 84, nozzle; 9, support ridge; 10, water eliminator. Detailed implementation manners

[0023] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0024] In the description of the present invention, it should be understood that the terms "opening", "upper", "lower", "thickness", "top", "middle", "length", "inner", "periphery", etc. indicating orientation or positional relationship are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the components or elements 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.

[0025] The following will describe Figures 1 - 14 the wastewater treatment device and method for the production of N-ethylpiperazine provided by the embodiments of the present invention.

[0026] Embodiment 1. For this embodiment, please refer to Figures 1 - 11 .

[0027] The embodiments of the present invention provide a wastewater treatment device for the production of N-ethylpiperazine, including a pH adjustment tank 100 and a stripping tower arranged in sequence. The pH adjustment tank 100 is used to adjust the pH of the wastewater so that the pH of the wastewater entering the stripping tower reaches the stripping value. Among them, the stripping tower includes: a tower body 4. An air inlet 41 is arranged below one side of the tower body 4 for introducing gas. A drain outlet 46 is arranged below the other side of the tower body 4. A conical head 44 is arranged at the top of the tower body 4. A water separator 10 is installed at the lower end inside the conical head 44. An exhaust port 43 is arranged at the upper end of the conical head 44.

[0028] And, a packing bed 5 is arranged inside the tower body 4. In this embodiment, as shown in Figure 2 and Figure 3 , three layers of packing beds 5 are arranged. A water distributor 8 is arranged above each packing bed 5. After alkalizing the wastewater (the pH of the wastewater needs to be greater than 10), it is distributed from top to bottom onto the packing bed 5 through the water distributor 8. The gas passes through the packing bed 5 from bottom to top. The gas and the liquid react inside the packing. The generated ammonia gas ascends and is discharged from the exhaust port 43 after being dewatered by the water separator 10. The discharged ammonia gas needs to be further treated before it can be discharged.

[0029] Preferably, a manhole 42 is also arranged in the area of the tower body 4 opposite to the packing bed 5.

[0030] Combined with Figures 3 - 6 as shown, the above-mentioned packing bed 5 is different from that in the prior art. The packing bed 5 includes a fixed bed 51 that is relatively stationary with respect to the tower body 4 and at least one movable bed 52 located above the fixed bed 51. The packing is placed on the upper surfaces of the fixed bed 51 and the movable bed 52, that is, the space between the fixed bed 51 and the movable bed 52 is filled with packing, and there is also packing above the movable bed 52, so as to be able to form a state where a single packing bed 5 has multiple layers of packing, that is, the packing on a single packing bed 5 is arranged in layers.

[0031] The reason for arranging them in layers is that once the flooding phenomenon occurs during use, the packings of each layer can be separated, thereby expanding the axial gap of each layer of packing in the tower body 4, and also reducing the pressure drop of the packing, so that the liquid can flow through the packing quickly, avoiding the situation that the equipment cannot continue to operate due to the flooding phenomenon.

[0032] Preferably, the packing in this embodiment is small-sized packing balls or Pall rings.

[0033] For this purpose, a lifting mechanism 7 is also provided. The detector is located on the inner wall of the tower body 4, and the position of the detector is higher than the uppermost movable bed 52 of the packing bed 5. The lifting mechanism 7 is arranged on the tower body 4 and is used to lift the movable bed 52, expand the axial gap of the packing, reduce the pressure drop of the packing, and enable the liquid that has flooded to flow downward through the packing.

[0034] Preferably, the detector is a liquid level sensor 6.

[0035] During use, once the detector detects that the flooding phenomenon has occurred above the corresponding packing bed 5, the controller controls the lifting mechanism 7 to work at this time, thereby adjusting the axial position of the movable bed 52, changing the axial spacing of each layer of packing, and making the packing sparse axially, ensuring that the liquid can flow downward and the gas can flow upward.

[0036] Therefore, the wastewater treatment device for N-ethylpiperazine production provided by the embodiment of the present invention can detect the occurrence of the flooding phenomenon, and can quickly solve the problem of flooding, avoiding the situation that the equipment cannot continue to work due to flooding.

[0037] Preferably, the above-mentioned lifting mechanism 7 can maintain the height of the movable bed 52 for a fixed duration after lifting. For example, if the flooding phenomenon can be solved by maintaining for 5 minutes, the movable bed 52 is maintained at the lifted height for 5 minutes after being lifted. The specific maintenance time is determined by the diameter of the tower body 4.

[0038] Preferably, a support ridge 9 is provided on the inner wall of the tower body 4 to fix the fixed bed 51 on the support ridge 9.

[0039] Combined with Figures 3 - 7As shown in the figure, in this embodiment, two movable beds 52 are provided for each packing bed 5, and these two movable beds 52 are arranged side by side vertically. The lifting mechanism 7 includes a lifting rod 72, and the lower end of the lifting rod 72 is rotationally assembled at the center of the movable bed 52, that is, the lifting rod 72 is in a rotatable state. The above-mentioned movable bed 52 includes a central sphere 523 concentric with the tower body 4. A through hole is opened at the center of the central sphere 523, and a slider 524 is arranged in the through hole. The lifting rod 72 is located in the through hole, and a spiral groove 721 adapted to the slider 524 is arranged on the lifting rod 72. When the lifting rod 72 rotates, the spiral groove 721 can push the slider 524 to move along the axial direction of the tower body 4, so that the two movable beds 52 move along the axial direction of the tower body 4, separating the packing layers.

[0040] Preferably, the spiral height of the spiral groove 721 above the same lifting rod 72 is greater than the spiral height of the spiral groove 721 below, so that the upward travel distance of an upper movable bed 52 pushed by an upper spiral groove 721 is greater than the upward travel distance of a lower movable bed 52 pushed by a lower spiral groove 721, realizing the separation of the bed layers on the same packing bed 5.

[0041] Furthermore, the above-mentioned lifting mechanism 7 further includes a driving shaft 73. The driving shaft 73 is arranged above the packing bed 5 along the radial direction of the tower body 4, and a driving structure 71 for driving the driving shaft 73 to rotate is arranged outside the tower body 4. The driving structure 71 is composed of a motor and a gear. A driving bevel gear 74 is installed on the driving shaft 73, and a driven bevel gear 75 is installed at the upper end of the lifting rod 72, thereby realizing the rotation of the lifting rod 72.

[0042] Preferably, an external joint 45 is arranged in the area of the side wall of the tower body 4 opposite to the driving shaft 73. The driving shaft 73 passes through the external joint 45. In addition, a plug is required to be arranged in the external joint 45 to block the external joint 45, and the driving shaft 73 passes through the plug.

[0043] As Figures 4 - 7 shown in the figure, in the above solution, the purpose of adjusting the axial clearance of the packing in the tower body 4 is achieved. However, it can only temporarily axially separate the packing. After the flooding problem is solved, each movable bed 52 still needs to be reset downward. After the reset, in order to reduce the probability of re-occurrence of flooding, it is best to rearrange the packing on the movable bed 52, so as to avoid the situation of repeated flooding caused by the excessive packing density due to the packing pressure drop. For this reason, the movable bed 52 here further includes spokes 522 and a mesh bed plate 521.

[0044] Specifically, the spokes 522 are radially rotatably mounted on the central sphere 523 through the pin shafts 526. Six spokes 522 are provided in the figure. One end of the spoke 522 close to the central sphere 523 is fixedly provided with an assembly head 527. An assembly groove 525 is opened on the outer side of the central sphere 523. The assembly head 527 is fixed on the pin shaft 526. Both ends of the pin shaft 526 are inserted into the side wall inside the assembly groove 525, and a torsion spring is arranged between the pin shaft 526 and the side wall of the assembly groove 525. In this embodiment, the spoke 522 can have a certain degree of freedom along the circumferential direction of the pin shaft 526. Preferably, the position of the spoke 522 is limited to be able to rotate 2° upward and 2° downward, that is, the overall degree of freedom of the spoke 522 is 4°.

[0045] In addition, the mesh bed plate 521 is of a fan-shaped structure, so that gas and liquid can pass through. The mesh bed plate 521 is located between two spokes 522, and one side of the mesh bed plate 521 is fixedly connected to an adjacent spoke 522. A convex ridge 3 is provided on the inner wall of the tower body 4 at a position corresponding to the rising section of the movable bed 52, as Figure 9 ; Preferably, the convex ridge 3 is of an annular structure.

[0046] In this embodiment, when the lifting rod 72 rotates and lifts the movable bed 52 upward, the mesh bed plate 521 and the spokes 522 pass over the convex ridge 3. When passing over the convex ridge 3, the spokes 522 and the mesh bed plate 521 are pushed, so that the two deflect downward. When passing over the convex ridge 3, due to the resetting action of the torsion spring, the original states of the spokes 522 and the mesh bed plate 521 are restored. As the spokes 522 and the mesh bed plate 521 pass over multiple convex ridges 3, the mesh bed plate 521 and the spokes 522 can form a vibrating state, and this vibration can make the packing vibrate, so that the gap of the packing along the radial direction of the tower body 4 is adjusted, avoiding the subsequent continuous flooding situation.

[0047] Therefore, the embodiment of the present invention can vibrate when the packing moves axially, the gap of the packing along the radial direction of the tower body 4 is adjusted, and the subsequent continuous flooding situation is avoided.

[0048] Substantially, due to the weight of the packing on the mesh bed plate 521, the mesh bed plate 521 and the spokes 522 are in a slightly downward deflected state when not in the lifted state, that is, the entire movable bed 52 is substantially an umbrella-shaped structure, as Figure 8 ; In order to prevent the mesh bed plate 521 and the spokes 522 from being overly deflected downward by the pressure of the packing in the natural state, substantially the convex ridge 3 can also play a role in supporting the edges of the mesh bed plate 521 and the spokes 522.

[0049] Referring to Figures 2 - 5 As shown, in order to make the alkalized wastewater evenly spray on the packing bed 5, a water distributor 8 is provided above the packing bed 5. The height of the water distributor 8 is greater than the height of the detector, and the height of the water distributor 8 is greater than the rising height of the movable bed 52.

[0050] Specifically, the water distributor 8 includes a main pipe 81, first-level branch pipes 82 located on both sides above the packing bed 5, second-level branch pipes 83 located on both sides of the first-level branch pipes 82, and spray heads 84 located below the first-level branch pipes 82 and the second-level branch pipes 83. A waste water inlet 11 is provided on the main pipe 81 for the alkaline waste liquid to enter the water distributor 8.

[0051] Preferably, the two second-level branch pipes 83 pass through the tower body 4 through external joints 45. The main pipe 81 is located outside the tower body 4 and is connected to the first-level branch pipes 82. In addition, a plug needs to be provided inside the external joint 45 to block the external joint 45, and the first-level branch pipes 82 pass through the plug.

[0052] Combined Figure 10 and Figure 11 As shown, furthermore, a drain port 46 is provided below one side of the tower body 4 for discharging the reacted water. During actual use, in order to better treat the waste water, a circulation buffer tank 1 is generally provided. The circulation buffer tank 1 is connected to the drain port 46. A circulation pump 2 is also connected to the circulation buffer tank 1. The water outlet of the circulation pump 2 is connected to the main pipe 81, so that the water discharged from the drain port 46 can be re-distributed by the water distributor 8 into the packing bed 5 through the circulation pump 2. A purified water outlet 12 is also provided above the circulation buffer tank 1.

[0053] During use (operation), the gas enters from the air inlet 41, the alkalized waste water enters the water distributor 8 from the waste water inlet 11, and is evenly distributed on the packing bed 5 by the water distributor 8. The gas and the liquid react in the packing to generate ammonia. The air and ammonia are dewatered by the water separator 10 and discharged from the exhaust port 43. The treated water enters the recirculation buffer tank 1 and is lifted to the water distributor 8 again by the circulation pump 2. The purified water outlet 12 is used to discharge the purified water with a higher liquid level in the circulation buffer tank 1.

[0054] After the water distributor 8 distributes water, once a flooding phenomenon occurs above the packing bed 5, the detector can detect it. At this time, the controller controls the driving structure 71 to work, so as to drive the lifting rod 72 to rotate through the driving shaft 73, the driving bevel gear 74, and the driven bevel gear 75. When the lifting rod 72 rotates, the spiral groove 721 can push the slider 524 to move along the axial direction of the tower body 4, so that the two movable beds 52 move along the axial direction of the tower body 4, separating the packing layers. After the movable bed 52 reaches the set height, it maintains this height for a period of time, and the controller controls the lifting rod 72 to rotate in the reverse direction again, so that the movable bed 52 returns downward. During the up and down movement of the movable bed 52, the ridge 3 can cause the movable bed 52 to vibrate, thereby rearranging the packing.

[0055] Embodiment 2, this embodiment refers to Figures 12 - 14 .

[0056] The difference between this embodiment and the first embodiment is that the lower end of the lifting rod 72 is fixed to the lower central ball 523, the upper end of the lifting rod 72 passes through the upper central ball 523, and can slide relative to the upper central ball 523. The upper end of the lifting rod 72 is fixedly provided with a top plate 723, and a certain height is reserved between the top plate 723 and the upper central ball 523.

[0057] After the upper central ball 523 is lifted to the height of the top plate 723, the lower central ball 523 can be lifted through the lifting rod 72, so that the distance between the lower movable bed 52 and the fixed bed 51 can be adjusted, and the distance between the lower movable bed 52 and the upper movable bed 52 can also be adjusted.

[0058] Specifically, the lifting mechanism 7 further includes an I-beam 78, the I-beam 78 is fixedly arranged above the tower body 4, and the I-beam 78 is located above the packing bed 5. Springs 77 are arranged between the I-beam 78 and the upper central ball 523, and springs 77 are arranged between the upper central ball 523 and the lower central ball 523. The two springs 77 here are used to rebound when the lower part of the lifting rod 72 no longer lifts the movable bed 52, so that the movable bed 52 is reset downward.

[0059] And in order to realize the rising and falling of the lifting rod 72, the lifting mechanism 7 further includes a driving shaft 73. The driving shaft 73 is located above the packing bed 5 and is arranged along the diameter direction of the tower body 4. A winding wheel 76 is provided in the area of the driving shaft 73 opposite to the central ball 523. A suspension rope 79 is connected between the winding wheel 76 and the upper central ball 523. When the driving shaft 73 rotates, the winding wheel 76 can wind or unwind the suspension rope 79. When the winding wheel 76 rotates forward, the suspension rope 79 is wound, and thus one upper movable bed 52 is first lifted upward. When one upper central ball 523 reaches the position of the top plate 723 upward, the top plate 723 can be dragged upward, and thus the lower movable bed 52 is driven to move upward through the lifting rod 72.

[0060] Preferably, a straight groove 722 is opened at a position near the upper part of the lifting rod 72, and a slider 524 is arranged in one upper central ball 523 for guiding the movement of one upper central ball 523.

[0061] In use (during operation), it is similar to the first embodiment, except that after the detector detects the flooding phenomenon, the controller controls the driving structure 71 to operate, so that the driving shaft 73 drives the reel 76 to rotate. The rotation of the reel 76 can wind up the lifting rope 79, so that the lifting rope 79 can lift an upper movable bed 52 upward and compress an upper spring 77, and stretch a lower spring 77. When an upper central ball 523 reaches the position of the top plate 723 upward, it can drag the top plate 723 to move upward, so that the lower movable bed 52 is driven to move upward by the lifting rod 72. After reaching the specified position, due to the sparse arrangement of the packing, the flooding problem can be solved.

[0062] In a second aspect, the present invention also provides a wastewater treatment method for N-ethylpiperazine production, which uses the above-mentioned wastewater treatment device for N-ethylpiperazine production to treat, and it includes the following steps: Step 1: Add alkali to the wastewater in the pH adjustment tank 100 to make the pH of the wastewater > 10; Step 2: Pass the alkalized wastewater into the above-mentioned stripping tower for stripping to remove NH3 in the wastewater; Step 3: Sequentially pass the liquid obtained in Step 2 into the pH neutralization tank, sedimentation tank and biological treatment tower, and finally drain the water. Neutralize the residual alkali (OH - ) in the wastewater after stripping in the pH neutralization tank. Add a flocculant in the sedimentation tank to remove colloidal organic matter (such as some undegraded ethylpiperazine polymers) and suspended solids. The biological treatment tower treats dissolved organic matter (such as residual ethylpiperazine, intermediate product acetic acid, amines) and residual ammonia nitrogen (NH4 remaining after stripping + , usually < 100 mg / L).

[0063] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device.

[0064] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and variations can be made according to the content of this specification. These embodiments are selected and specifically described in this specification to better explain the principles and practical applications of the present invention, so that those skilled in the art can well understand and utilize the present invention. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. A wastewater treatment device for the production of N-ethylpiperazine, characterized in that, It includes a pH adjustment tank (100) and a stripping tower arranged in sequence. The pH adjustment tank (100) is used to adjust the pH of the wastewater so that the pH of the wastewater entering the stripping tower reaches the stripping value. Among them, the stripping tower includes: A tower body (4); A packing bed (5), the packing bed (5) is located inside the tower body (4), and the packing bed (5) includes a fixed bed (51) relatively stationary with the tower body (4) and at least one moving bed (52) located above the fixed bed (51). Packing is placed on the upper surfaces of the fixed bed (51) and the moving bed (52) to form a state where the packing in a single packing bed (5) is arranged in layers. A detector, the detector is located on the inner wall of the tower body (4), and the position of the detector is higher than the uppermost moving bed (52) of the packing bed (5), and is used to detect whether a flooding phenomenon occurs. A lifting mechanism (7), the lifting mechanism (7) is arranged on the tower body (4) and is used to lift the moving bed (52), expand the axial gap of the packing, reduce the pressure drop of the packing, and enable the flooded liquid to flow downward through the packing.

2. The wastewater treatment device for the production of N-ethylpiperazine according to claim 1, characterized in that: Each packing bed (5) includes two moving beds (52) arranged side by side up and down. The lifting mechanism (7) includes a lifting rod (72), and the action of the lifting rod (72) can change the distance between the two moving beds (52) relative to the fixed bed (51).

3. The wastewater treatment device for the production of N-ethylpiperazine according to claim 2, wherein: The lower end of the lifting rod (72) is rotationally assembled at the center of the moving bed (52); The moving bed (52) includes a central sphere (523) concentric with the tower body (4). A through hole is opened at the center of the central sphere (523), and a slider (524) is arranged in the through hole. A spiral groove (721) adapted to the slider (524) is arranged on the lifting rod (72); The spiral height of the spiral groove (721) above the same lifting rod (72) is greater than the spiral height of the spiral groove (721) below; The rotation of the lifting rod (72) can drive the two moving beds (52) to move axially along the tower body (4) through the spiral groove (721) and the slider (524).

4. The wastewater treatment device for the production of N-ethylpiperazine according to claim 2, wherein: The lower end of the lifting rod (72) is fixed on the lower central sphere (523). The upper end of the lifting rod (72) passes through the upper central sphere (523) and can slide relative to the upper central sphere (523). A top plate (723) is fixedly arranged at the upper end of the lifting rod (72), and a height is reserved between the top plate (723) and the upper central sphere (523); After the upper central sphere (523) is lifted to the height of the top plate (723), the lower central sphere (523) can be lifted through the lifting rod (72).

5. The wastewater treatment device for the production of N-ethylpiperazine according to claim 4, characterized in that: The lifting mechanism (7) further includes an I-beam (78). The I-beam (78) is fixedly arranged above the tower body (4), and the I-beam (78) is located above the packing bed (5). A spring (77) is arranged between the I-beam (78) and the upper central sphere (523), and a spring (77) is arranged between the upper central sphere (523) and the lower central sphere (523).

6. The wastewater treatment device for the production of N-ethylpiperazine according to claim 5, characterized in that: The lifting mechanism (7) further includes a driving shaft (73) which is located above the packing bed (5) and arranged along the diameter direction of the tower body (4). A winding wheel (76) is provided in the area of the driving shaft (73) opposite to the central sphere (523). A suspension rope (79) is connected between the winding wheel (76) and the upper central sphere (523). The rotation of the driving shaft (73) can wind or unwind the suspension rope (79) by the winding wheel (76).

7. A wastewater treatment device for the production of N-ethylpiperazine according to any one of claims 2-6, characterized in that: The moving bed (52) further includes: Spokes (522) which are radially arranged and rotatably mounted on the central sphere (523) through pin shafts (526). A torsion spring is arranged between the pin shafts (526) and the central sphere (523). A mesh bed plate (521) which is of a sector structure. The mesh bed plate (521) is located between two spokes (522), and one side of the mesh bed plate (521) is fixedly connected to an adjacent spoke (522). A ridge (3) is provided on the inner wall of the tower body (4) corresponding to the rising section of the moving bed (52). When the moving bed (52) moves axially along the tower body (4), the resistance of the ridge (3) can cause vibration to adjust the gap of the packing along the radial direction of the tower body (4).

8. The wastewater treatment device for the production of N-ethylpiperazine according to claim 7, characterized in that: A water distributor (8) is provided above the packing bed (5). The height of the water distributor (8) is greater than the height of the detector, and the height of the water distributor (8) is greater than the rising height of the moving bed (52). A drain port (47) is provided below one side of the tower body (4).

9. The wastewater treatment device for the production of N-ethylpiperazine according to claim 8, wherein: An air inlet (41) is provided below the other side of the tower body (4) away from the drain port (47). A water eliminator (10) is provided at the upper end inside the tower body (4), and an exhaust port (43) is provided above the water eliminator (10).

10. A wastewater treatment method for the production of N-ethylpiperazine, which is treated using the wastewater treatment device for the production of N-ethylpiperazine according to any one of claims 1-9, characterized in that, It includes the following steps: Step 1: Add alkali to the wastewater in the pH adjustment tank (100) to make the pH of the wastewater > 10. Step 2: Feed the alkalized wastewater into the stripping tower for stripping to remove NH3 in the wastewater. Step 3: Feed the liquid obtained in Step 2 into the pH neutralization tank, sedimentation tank and biological treatment tower in sequence, and finally drain the water.

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