Multi-stage treatment device for detergent preparation wastewater
By using a floating defoaming drum defoamer in a multi-stage treatment device for wastewater from detergent preparation, the problem of foam generation in wastewater treatment from detergent preparation was solved, achieving efficient mechanical defoaming, reducing costs and avoiding chemical pollution.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- QINGDAO KANGLU BIOTECHNOLOGY CO LTD
- Filing Date
- 2026-04-24
- Publication Date
- 2026-06-16
AI Technical Summary
Wastewater from cleaning agent preparation generates a large amount of foam during treatment. Existing defoaming technologies are costly and ineffective, chemical treatment causes secondary pollution, and mechanical treatment is complex and has high maintenance costs.
Design a multi-stage treatment device for cleaning agent preparation wastewater, including an equalization tank, a physical treatment tank, a chemical treatment tank, and a secondary sedimentation tank. A floating defoaming drum defoamer is installed in the tank, which uses the flow of wastewater to drive the drum to roll for physical defoaming, avoiding additional power drive and complex liquid level adaptation mechanism.
It achieves mechanical defoaming without the need for chemical defoamers, reducing treatment costs, avoiding secondary pollution, and providing significant defoaming effect, ensuring treatment efficiency and environmental safety.
Smart Images
Figure CN122212418A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of wastewater treatment technology, and in particular to a multi-stage treatment device for wastewater from cleaning agent preparation. Background Technology
[0002] The preparation of cleaning agents generates a large amount of wastewater. Unlike other wastewater, this wastewater contains a high concentration of anionic surfactants. During physical or chemical treatment in various treatment tanks, it easily produces a large amount of stable foam. This foam overflows from the tank tops, polluting the operating environment and treatment equipment, creating slippery floors and safety hazards, and reducing treatment efficiency. Therefore, timely foam removal is crucial during the treatment of cleaning agent preparation wastewater.
[0003] In existing defoaming technologies, some methods involve adding defoamers as a chemical treatment. However, this chemical treatment introduces new pollution (from the defoamer), leading to increased processing steps and a sharp rise in costs. Existing technologies also include mechanical treatment methods that break up foam using a rotating scraper. However, this method typically requires additional components to drive the scraper and a control system. Furthermore, the scraper needs to be adaptable to different liquid levels in the tank, resulting in higher manufacturing and maintenance costs, and poorer defoaming effectiveness. Summary of the Invention
[0004] This invention provides a multi-stage treatment device for wastewater from cleaning agent preparation, which can effectively solve the problems in the background art.
[0005] The present invention provides a multi-stage treatment device for cleaning agent preparation wastewater, comprising an equalization tank, a physical treatment tank, a chemical treatment tank and a secondary sedimentation tank arranged sequentially along the wastewater treatment direction; Equalization tanks are used for aeration and mixing of wastewater; Physical treatment tanks are used to remove solid impurities from wastewater; The chemical treatment tank is arranged in sequence along the wastewater treatment direction, including a demulsification zone, a coagulation zone, and a flocculation zone. The demulsification zone is used to break the emulsion structure of the wastewater, the coagulation zone is used for the destabilization and coagulation of organic matter, and the flocculation zone is used for the growth of micro flocs. Secondary sedimentation tanks are used for separating mud and water in treated wastewater; It also has a sludge pond for collecting sludge; It is also equipped with a dosing system for adding chemicals to the chemical treatment tank; At least one defoamer shall be installed in the equalization tank, physical treatment tank and chemical treatment tank; The defoamer includes a defoaming roller that floats on the liquid surface.
[0006] Furthermore, the bottoms of the equalization tank, physical treatment tank, and secondary sedimentation tank are all conical or curved structures.
[0007] Furthermore, an inlet pipe is installed at the top center of the secondary sedimentation tank, and a conical or flat reflector is installed at the lower end of the inlet pipe.
[0008] Furthermore, the sludge tank is equipped with a stirrer and a sludge lift pump to send the concentrated sludge to the filter press for dewatering and return the supernatant to the equalization tank.
[0009] Furthermore, the defoamer includes multiple defoaming units arranged vertically, each defoaming unit including a defoaming roller and two flow channels symmetrically arranged above and below the defoaming roller; The defoaming roller is located in the middle section of the flow channel; An inlet is formed between one end of the two flow channels; an outlet is formed between the other ends of the two flow channels. The maximum cross-sectional diameter of the defoaming roller is greater than the width of the inlet and outlet.
[0010] Furthermore, within each defoaming unit, a first structural plate is provided above and below the defoaming roller, and the two closest first structural plates between two adjacent defoaming units are fixed on a second structural plate, the second structural plate having a C-shaped cross-section.
[0011] Furthermore, each first structural piece has multiple first deformation sections and second deformation sections alternately arranged at the end near the inlet; Each first structural piece is provided with a first connecting plate, a second connecting plate, and a third connecting plate forming a tubular structure at one end near the outlet. The first deformation section is connected to the first connecting plate; the second deformation section is connected to the third connecting plate.
[0012] Furthermore, the defoamer also includes a mounting plate, on which all defoaming units are fixedly mounted; The mounting plate has multiple through holes aligned with the outlet, and a downward-extending guide plate is installed at each through hole.
[0013] Furthermore, the lowest point of the diversion plate is lower than the lowest point of the defoaming roller.
[0014] Furthermore, the outer surface of the defoaming roller is provided with an uneven defoaming structure.
[0015] The technical solution of this invention can achieve the following technical effects: This invention incorporates a defoamer with a floating defoaming roller in each of the equalization tank, physical treatment tank, and chemical treatment tank. The defoamer relies on the natural flow of wastewater to drive the roller's rotation, physically breaking down foam through the pressure between the roller and the liquid surface. This eliminates the need for additional power or complex liquid level adjustment mechanisms, resulting in a simple structure and significantly reduced wastewater treatment costs. Furthermore, this defoamer utilizes entirely mechanical defoaming, avoiding secondary pollution problems associated with chemical defoamers and eliminating the need for additional subsequent treatment processes, further reducing wastewater treatment costs. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 A schematic diagram of a multi-stage treatment device for wastewater from cleaning agent preparation; Figure 2 A schematic diagram of the structure at the installation location of the defoamer; Figure 3 A structural schematic diagram of the defoamer installation location from another perspective; Figure 4 This is a cross-sectional view of the defoamer; Figure 5 This is a schematic diagram of the structure of the first structural piece; Figure 6 A bending diagram illustrating the fabrication of the first structural piece; Figure 7 This is a schematic diagram of the defoaming roller.
[0018] Reference numerals: 1. Equalization tank; 2. Physical treatment tank; 3. Chemical treatment tank; 4. Secondary sedimentation tank; 5. Sludge tank; 6. Feeding system; 7. Defoamer; 71. Defoaming roller; 72. First structural plate; 72a. First deformation section; 72b. Second deformation section; 72c. First connecting plate; 72d. Second connecting plate; 72e. Third connecting plate; 73. Second structural plate; 74. Mounting plate; 74a. Drainage plate. Detailed Implementation
[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.
[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0021] This invention relates to a multi-stage treatment device for wastewater from cleaning agent preparation, such as... Figure 1 As shown, the system includes an equalization tank 1, a physical treatment tank 2, a chemical treatment tank 3, and a secondary sedimentation tank 4 arranged sequentially along the wastewater treatment direction. The specific structure and function of each treatment tank are as follows: The equalization tank 1 is used for wastewater aeration and mixing. The equalization tank 1 adopts a rectangular reinforced concrete structure or a carbon steel corrosion-resistant box structure. A sealed cover plate is installed on the top of the equalization tank 1, with a maintenance manhole and observation window on the cover plate. Perforated aeration pipes are installed at the bottom of the equalization tank 1, and electric valves and gas flow meters are installed on the aeration pipes to achieve automatic control of intermittent aeration. An automatic defoamer dripping device is also installed above the equalization tank 1. This device includes a defoamer storage tank, a metering pump, and a foam sensor. When the foam sensor detects that the foam height exceeds a set threshold, the metering pump automatically starts to drip polyether defoamer into the tank.
[0022] Physical treatment tank 2 primarily removes solid impurities from wastewater through physical screening. Physical treatment tank 2 is a shallow rectangular flotation tank with a body made of corrosion-resistant carbon steel or stainless steel. An inlet pipe leading to the bottom of physical treatment tank 2 ensures that wastewater reaches the bottom directly upon entering, effectively reducing the generation of impact foam. Solid impurities are then trapped at the bottom of physical treatment tank 2 by a physical filtration system and discharged. The filtered upper layer of wastewater is then sent to chemical treatment tank 3.
[0023] Chemical treatment tank 3 is arranged sequentially along the wastewater treatment direction, comprising a demulsification zone, a coagulation zone, and a flocculation zone. These zones are isolated from each other but connected by baffles. The functions of each zone within chemical treatment tank 3 are as follows: Demulsification zone: Add acid (dilute sulfuric acid or dilute hydrochloric acid) to this zone to adjust the pH of the wastewater to 3-4, thereby breaking the emulsification structure of the surfactant and causing the dissolved organic matter to precipitate out into a suspended state. If necessary, add a stirrer to this zone for stirring, so that the demulsification reaction can proceed evenly and quickly. Coagulation zone: Add polyaluminum chloride (PAC) to this zone and stir rapidly to destabilize and coagulate the demulsified organic matter; Flocculation zone: Polyacrylamide (PAM) is added to this zone and stirred slowly to allow the tiny flocs to grow into dense, large particles of impurities. The wastewater containing these large particles is then directly introduced into the secondary sedimentation tank.
[0024] Secondary sedimentation tank 4 is used for sludge-water separation of treated wastewater. The bottom of secondary sedimentation tank 4 is equipped with a sludge discharge pipe to discharge the settled sludge into a sludge tank; the upper part of secondary sedimentation tank 4 is equipped with an overflow weir, which is a sawtooth triangular weir, so that the qualified supernatant flows out of secondary sedimentation tank 4 by overflow, and then the overflow supernatant can be discharged or reused.
[0025] The wastewater treatment unit is also equipped with a sludge tank 5, which is used to collect sludge generated from the equalization tank 1, the physical treatment tank 2 and the secondary sedimentation tank 4. The sludge tank 5 is equipped with a stirrer and a sludge lift pump to send the concentrated sludge to the filter press for dewatering, and the supernatant is returned to the equalization tank.
[0026] The wastewater treatment device is also equipped with a dosing system 6, which includes multiple reagent storage tanks and metering pumps for dosing the corresponding reagents into each of the three areas of the chemical treatment pool.
[0027] During wastewater transportation and treatment, timely defoaming is necessary to prevent foam overflow. This device includes at least one defoamer 7 in each of the equalization tank 1, physical treatment tank 2, and chemical treatment tank 3 to eliminate foam in each tank. The main structure of the defoamer 7 includes a defoaming roller 71, made of lightweight plastic, balsa wood, etc., allowing it to float on the liquid surface. The defoaming roller 71 needs to be confined within a certain space. When wastewater flows, this confined space prevents the defoaming roller 71 from being washed away; instead, the flowing wastewater causes the defoaming roller 71 to roll on the water surface. As it rolls, the defoaming roller 71 delivers foam between itself and the liquid surface, where the pressure from the roller breaks the foam, thus achieving the defoaming function. The defoaming roller 71 can be hollow or solid.
[0028] Preferably, the bottoms of the equalization tank 1, the physical treatment tank 2, and the secondary sedimentation tank 4 are all conical or curved. Solid impurities are generated during the treatment process in these tanks. The conical or curved bottoms allow the solid impurities to concentrate in the middle of the tank bottom under gravity, making it easier to discharge the sludge from the tank.
[0029] Preferably, an inlet pipe is installed at the top center of the secondary sedimentation tank 4, so that the secondary sedimentation tank 4 forms a central water inlet. A conical or flat reflector plate is installed at the lower end of the inlet pipe, with a cone angle of 120°~150° and a diameter of 1.5~2 times the diameter of the central pipe. When the treated wastewater enters the secondary sedimentation tank 4, the reflector plate changes the direction of the inlet water flow, so that the water flow presents a downward and outward diffusion flow state, reducing the disturbance to the sediment in the middle of the tank.
[0030] Preferably, a stirrer and a sludge lift pump are installed in the sludge tank 5. The stirrer operates intermittently to prevent sludge caking. The sludge lift pump sends the concentrated sludge to a filter press for dewatering and returns the supernatant to the equalization tank 1 to prevent untreated wastewater from being carried out with the concentrated sludge.
[0031] In environments with low foam levels, the simplest way to install the defoaming roller 71 is to install a vertical slider in each treatment tank, and then rotate and install a single defoaming roller 71 (or several defoaming rollers 71 distributed at the same height) on the slider. This ensures that the defoaming roller 71 can rotate and move up and down, allowing it to move with changes in the liquid level and always remain on the liquid surface. However, in cases involving wastewater generated from the preparation of cleaning agents, due to the large amount of foam, the foam will overflow from the top of the defoaming roller 71 and cross over it, resulting in poor defoaming effect.
[0032] Therefore, this application has made a new design for the defoamer 7 for this specific application, such as... Figures 2-4 As shown, the defoamer 7 includes multiple defoaming units arranged vertically. Each defoaming unit includes a defoaming roller 71 and two flow channels symmetrically arranged above and below the defoaming roller 71.
[0033] An inlet is formed between one end of the two flow channels; an outlet is formed between the other ends of the two flow channels; the maximum cross-sectional diameter of the defoaming roller 71 is greater than the width of the inlet and outlet, thus creating a space in the middle section of the flow channel in which the defoaming roller 71 cannot escape. The defoaming roller 71 is located in this inescapable space in the middle section of the flow channel. Both the inlet and outlet have a structure that gradually expands from the outside to the inside.
[0034] The principle of the above-mentioned defoamer 7 structure is as follows: Figure 4 As shown, when the liquid level does not reach the corresponding defoaming unit (e.g.) Figure 4 The defoaming unit in the upper middle section), the defoaming roller 71 blocks the flow channel in the lower part of the defoaming unit. When a lot of foam enters the defoaming unit, it will only enter the upper flow channel. However, because the upper flow channel has a large bend, it can effectively block the foam on one side of the inlet, thereby limiting the foam from running to the other side of the defoamer 7. In this way, even if the foam is very high, it can be blocked by the upper defoaming unit.
[0035] When the liquid level reaches the corresponding defoaming unit (e.g.) Figure 4 The defoaming unit is located in the lower middle section. Water flows into the defoaming unit through the inlet. After the defoaming roller 71 floats up, the flow channel at the bottom of the defoaming unit opens. When the water flows through the flow channel at the bottom, it will drive the defoaming roller 71 to rotate, thereby squeezing the foam to achieve the defoaming function. As the defoaming roller 71 floats up, the foam that was previously stored in the upper flow channel will also be squeezed. Furthermore, due to the rotation of the defoaming roller 71, the foam can also be quickly drawn into the bottom of the defoaming roller 71 for squeezing, thus achieving rapid defoaming.
[0036] The upper and lower flow channels of the defoaming unit can be manufactured in various ways, such as traditional milling and drawing processes. However, these manufacturing processes are costly. Therefore, this defoamer 7 has undergone the following optimized design: Within each defoaming unit, a first structural piece 72 is provided above and below the defoaming roller 71. The two closest first structural pieces 72 between two adjacent defoaming units are fixed to a second structural piece 73, the second structural piece 73 having a C-shaped cross-section. Both the first structural piece 72 and the second structural piece 73 can be obtained by stamping and bending a metal sheet, thus greatly reducing manufacturing costs.
[0037] Due to the impact of the water flow, if the two ends of the second structural piece 73 are simply bent to form a bend, the end of the second structural piece 73 near the outlet is prone to shaking under the impact of the water flow. This shaking will splash the water surface and form new foam. To avoid this problem, this device has modified the first structural piece 72 as follows: Figures 5-6 Optimized design: Each first structural piece 72 has multiple alternating first deformation sections 72a and second deformation sections 72b near the inlet end, and the first deformation sections 72a and second deformation sections 72b are all mounted on the second structural piece 73. Each first structural piece 72 is provided with a first connecting plate 72c, a second connecting plate 72d and a third connecting plate 72e forming a tubular structure at one end near the outlet. The tubular structure is usually triangular. The first deformation section 72a is connected to the first connecting plate 72c; the second deformation section 72b is connected to the third connecting plate 72e.
[0038] The above structure, while ensuring that the first structural piece 72 can be formed into a single unit through stamping and bending, adds a tubular structure to the first structural piece 72. The tubular structure is connected to the first deformation section 72a and the second deformation section 72b on both sides. When water flows and impacts the tubular structure, the impact pressure on the first deformation section 72a and the second deformation section 72b will be different, resulting in different deformation trends and degrees. Since the water flow is a low-impact, low-frequency impact, these different deformation trends are unlikely to generate high-frequency resonant sloshing, thus avoiding new foam generated by sloshing and splashing on the water surface. Furthermore, this structure can reduce the material used in the first structural piece 72, thereby reducing the overall structural weight of the defoamer 7.
[0039] To prevent the defoamed water from generating new foam due to turbulence when exiting the defoamer 7, it is preferable to also install a mounting plate 74 inside the defoamer 7, on which all defoaming units are fixedly mounted. The mounting plate 74 has multiple through holes aligned with the outlet, and downward-extending guide plates 74a are installed at these through holes. This way, when the water flows out of the outlet, it is guided and confined by the guide plates 74a to quickly enter below the liquid surface, thus preventing the generation of new foam. Preferably, the lowest point of each guide plate 74a is lower than the lowest point of the defoaming roller 71 of the corresponding defoaming unit. With this structure, the guide plates 74a extend directly below the liquid surface, thereby helping the water flow quickly enter the subsequent foam-free liquid.
[0040] The defoamer 7 can be directly fixed inside each treatment tank by means of screw fixing or welding; or it can be installed in a trough-shaped structure inside the treatment tank, and the two sides of the defoamer 7 can be placed into the trough-shaped structure to achieve detachable installation of the defoamer 7, so as to facilitate personnel to install and remove the defoamer 7 for cleaning.
[0041] Preferably, the outer surface of the defoaming roller 71 has an uneven defoaming structure, such as knurling, small cone, or square cone structure, etc. Figure 7 As shown, this allows more foam to be drawn into the extrusion position during operation of the defoaming roller 71, and the foam surface can be quickly broken during extrusion, thereby effectively improving defoaming efficiency. However, this may result in excessive friction between the outer surface of the defoaming roller 71 and the sidewall of the confining space, making rotation difficult. In this case, multiple abutment rings can be provided on the outer surface of the defoaming roller 71. The diameter of the abutment rings is larger than the uneven defoaming structure, and the outer surface of the abutment rings is smooth. This ensures that the contact surface with the sidewall of the confining space is smooth and will not affect the rotation of the defoaming roller 71.
[0042] Taking the treatment of wastewater generated from the production of a certain cleaning agent as an example, the effect of the present invention will be further explained: The daily treatment capacity of the wastewater is 10 tons, and the influent water quality is: COD is about 12000 mg / L, anionic surfactant (LAS) is about 800 mg / L, pH is about 9.5, dynamic foam is easily generated, and the foam height is >30 cm when continuously treated (continuously added to the tank for 1 hour).
[0043] After using this treatment device, the foam condition in each pool is as follows: 1. Equalization tank treatment: Wastewater enters the equalization tank, where perforated aeration pipes provide intermittent aeration (30 minutes every 2 hours). A foam sensor with a threshold of 20cm is set; when the foam height exceeds 20cm, polyether defoamer (approximately 50mg / L) is automatically added. Testing shows that the foam height on the water surface in the equalization tank is consistently controlled within 3cm, with no foam overflow. The effluent then enters the physical treatment tank.
[0044] 2. Physical treatment tank treatment: The incoming water is buffered through the guide channel and enters the tank smoothly without generating any impact foam. During the filtration process, a small amount of foam appears on the surface of the tank, which is basically eliminated by the defoamer. The water surface in the conditioning tank is almost foam-free, and most of the liquid level can be directly observed.
[0045] 3. Chemical treatment tank treatment: Demulsification zone: Add dilute sulfuric acid to adjust the pH to 3.5, react with a low-shear stirrer (70 rpm) for 25 minutes to demulsify and precipitate surfactants. The top of this zone is covered by a spray pipe that is activated every 30 minutes to keep the liquid surface free of foam. Coagulation zone: Add PAC 300mg / L, stir at low shear (150rpm) for 10min; Flocculation Zone: Add PAM 5mg / L, stir at low shear (35rpm) for 10min, and continuously micro-spray from the top spray pipe in this zone (flow rate 0.5m). 3 / h).
[0046] The defoamers in the three reaction zones (250mm above the liquid surface and 400mm submerged) effectively prevent foam from entering the outlet. The effluent COD is reduced to approximately 2500mg / L, LAS to approximately 100mg / L, and the removal rate is approximately 87.5%. The effluent then enters the secondary sedimentation tank.
[0047] 4. Secondary sedimentation tank treatment: Settled sludge is discharged into a sludge tank with a return ratio of 80%. The top auxiliary spray pipe is activated only when foaming occurs (only twice during operation). The supernatant has a COD of approximately 2000 mg / L and a LAS of approximately 100 mg / L, meeting the pretreatment standards and ready for subsequent fine treatment steps.
[0048] 5. Sludge tanks and reuse: The sludge tank collects scum and sludge, which are then dewatered by a screw press. The resulting sludge cake has a moisture content of approximately 80% and is transported off-site for disposal. The filtrate is returned to the equalization tank. The clean water reuse pump delivers the effluent from the secondary sedimentation tank to each spray defoaming pipe for recycling.
[0049] After 60 days of continuous operation, there was no foam overflow in any of the pools, the operating environment was clean, and the system operated stably.
[0050] Although this application has been described in conjunction with specific features and embodiments, it is obvious that various modifications and combinations can be made thereto without departing from the spirit and scope of this application. Accordingly, this specification and drawings are merely exemplary illustrations of the application as defined herein, and are to be considered as covering any and all modifications, variations, combinations, or equivalents within the scope of this application. Clearly, those skilled in the art can make various alterations and modifications to this application without departing from its scope. Thus, if such modifications and modifications fall within the scope of this application and its equivalents, this application intends to include such modifications and modifications.
Claims
1. A multi-stage treatment device for wastewater from cleaning agent preparation, characterized in that, It includes an equalization tank (1), a physical treatment tank (2), a chemical treatment tank (3), and a secondary sedimentation tank (4) arranged sequentially along the wastewater treatment direction; The equalization tank (1) is used for aeration and mixing of wastewater; The physical treatment tank (2) is used to remove solid impurities from the wastewater; The chemical treatment tank (3) is provided with a demulsification zone, a coagulation zone and a flocculation zone in sequence along the wastewater treatment direction. The demulsification zone is used to destroy the emulsified structure of the wastewater, the coagulation zone is used for destabilizing and coagulating organic matter, and the flocculation zone is used for the growth of micro flocs. The secondary sedimentation tank (4) is used to separate mud and water in the treated wastewater; A sludge pond (5) is also provided for collecting sludge; A dosing system (6) is also provided for dosing agents into the chemical treatment tank (3); At least one defoamer (7) is provided in the conditioning tank (1), the physical treatment tank (2) and the chemical treatment tank (3); The defoamer (7) includes a defoaming roller (71) that floats on the liquid surface.
2. The multi-stage treatment device for cleaning agent preparation wastewater according to claim 1, characterized in that, The bottoms of the equalization tank (1), the physical treatment tank (2), and the secondary sedimentation tank (4) are all conical or curved.
3. The multi-stage treatment device for cleaning agent preparation wastewater according to claim 1, characterized in that, The secondary sedimentation tank (4) is equipped with an inlet pipe at the top center, and a conical or flat reflector is installed at the lower end of the inlet pipe.
4. The multi-stage treatment device for cleaning agent preparation wastewater according to claim 1, characterized in that, The sludge tank (5) is equipped with a stirrer and a sludge lifting pump to send the concentrated sludge to the filter press for dewatering and return the supernatant to the equalization tank (1).
5. The multi-stage treatment device for cleaning agent preparation wastewater according to claim 1, characterized in that, The defoamer (7) includes a plurality of defoaming units arranged vertically, each of the defoaming units including a defoaming roller (71) and two flow channels symmetrically arranged above and below the defoaming roller (71); The defoaming roller (71) is located in the middle section of the flow channel; An inlet is formed between one end of the two flow channels; an outlet is formed between the other ends of the two flow channels. The maximum cross-sectional diameter of the defoaming roller (71) is greater than the width of the inlet and the outlet.
6. The multi-stage treatment device for cleaning agent preparation wastewater according to claim 5, characterized in that, In each of the defoaming units, a first structural piece (72) is provided above and below the defoaming roller (71), and the two closest first structural pieces (72) between two adjacent defoaming units are fixed on a second structural piece (73), the second structural piece (73) having a C-shaped cross section.
7. The multi-stage treatment device for cleaning agent preparation wastewater according to claim 6, characterized in that, Each of the first structural pieces (72) has a plurality of first deformation segments (72a) and second deformation segments (72b) alternately arranged at one end near the inlet; Each of the first structural pieces (72) has a first connecting plate (72c), a second connecting plate (72d), and a third connecting plate (72e) forming a tubular structure at one end near the outlet. The first deformable segment (72a) is connected to the first connecting plate (72c); the second deformable segment (72b) is connected to the third connecting plate (72e).
8. The multi-stage treatment device for cleaning agent preparation wastewater according to claim 5, characterized in that, The defoamer (7) also includes a mounting plate (74), and all the defoaming units are fixedly mounted on the mounting plate (74); The mounting plate (74) is provided with a plurality of through holes aligned with the outlet, and a downwardly extending guide plate (74a) is provided at the through holes.
9. The multi-stage treatment device for cleaning agent preparation wastewater according to claim 8, characterized in that, The lowest end of the diversion plate (74a) is lower than the lowest end of the defoaming roller (71).
10. The multi-stage treatment device for cleaning agent preparation wastewater according to claim 1, characterized in that, The outer surface of the defoaming roller (71) is provided with an uneven defoaming structure.