A papermaking wastewater treatment system

Abstract

The utility model relates to a kind of papermaking wastewater treatment systems, oxidation pond is connected with preliminary processing mechanism by detection pipeline, detection mechanism is set on detection pipeline, and detection mechanism is used to detect the COD concentration of wastewater in detection pipeline;First dosing box is connected with oxidation pond by pipeline, and first dosing box is used to provide ferrous sulfate solution to oxidation pond;First metering pump is set on the pipeline between first dosing box and oxidation pond;Second dosing box is connected with oxidation pond by pipeline;Second metering pump is set on the pipeline between second dosing box and oxidation pond, and second dosing box is used to provide hydrogen peroxide solution to oxidation pond;Third dosing box is connected with oxidation pond by pipeline;Third metering pump is set on the pipeline between third dosing box and oxidation pond, and third dosing box is used to provide polymeric ferric aluminum chloride solution to oxidation pond;Control mechanism is used to receive the detection signal of detection mechanism, and the start or close of first metering pump, second metering pump and third metering pump is controlled.

Description

Technical Field

[0001] This utility model relates to the field of papermaking wastewater treatment technology, and in particular to a papermaking wastewater treatment system. Background Technology

[0002] Waste paper, straw, and wood pulp are commonly used as raw materials in papermaking. The pulping and papermaking process generally consists of pulping, washing, bleaching, and papermaking steps. Pulping in the papermaking industry includes alkaline pulping, chemimechanical pulping, and mechanical pulping. Papermaking generates wastewater, and direct discharge of this wastewater will pollute the environment and is detrimental to environmental protection.

[0003] Currently, the workshop mainly uses the Fenton reaction method to reduce the COD concentration in wastewater in order to ensure that the wastewater meets the discharge standards. This method uses "ferrous sulfate and hydrogen peroxide" as Fenton reagents. Due to the high unit price of hydrogen peroxide and the large amount of Fenton reagent used, the unit price of wastewater treatment is high, resulting in high costs. Utility Model Content

[0004] Therefore, a papermaking wastewater treatment system is needed to address the current practice of using Fenton reaction to reduce COD concentration in wastewater and ensure that the wastewater meets discharge standards. This method uses ferrous sulfate and hydrogen peroxide as Fenton reagents. However, due to the high price of hydrogen peroxide and the large amount of Fenton reagent required, the unit price of wastewater treatment is high, resulting in high costs.

[0005] To achieve the above objectives, the inventors provide a papermaking wastewater treatment system, comprising:

[0006] A preliminary treatment unit is used to perform preliminary treatment on wastewater from the paper mill.

[0007] An oxidation tank, which is connected to the preliminary treatment unit via a detection pipeline.

[0008] A final settling tank, which is connected to the oxidation tank via a pipeline;

[0009] A detection mechanism is installed on the detection pipeline and is used to detect the COD concentration of wastewater in the detection pipeline;

[0010] A first dosing tank is connected to the oxidation tank via a pipeline, and the first dosing tank is used to provide ferrous sulfate solution to the oxidation tank;

[0011] A first metering pump is installed on the pipeline between the first dosing tank and the oxidation tank;

[0012] The second dosing tank is connected to the oxidation tank via a pipeline;

[0013] The second metering pump is installed on the pipeline between the second dosing tank and the oxidation tank. The second dosing tank is used to provide hydrogen peroxide solution to the oxidation tank.

[0014] The third dosing tank is connected to the oxidation tank via a pipeline;

[0015] The third metering pump is installed on the pipeline between the third dosing tank and the oxidation tank. The third dosing tank is used to supply polyaluminum ferric chloride solution to the oxidation tank.

[0016] The system includes a detection mechanism electrically connected to the control mechanism, a first metering pump electrically connected to the control mechanism, a second metering pump electrically connected to the control mechanism, and a third metering pump electrically connected to the control mechanism. The control mechanism is used to receive and process the detection signals from the detection mechanism and to control the start-up or shutdown of the first metering pump, the second metering pump, and the third metering pump.

[0017] As a preferred structure of this utility model, the papermaking wastewater treatment system further includes a first level gauge, a second level gauge, and a third level gauge;

[0018] The first level gauge is installed inside the first dosing tank, and the first level gauge is electrically connected to the control mechanism;

[0019] The second level gauge is installed inside the second dosing tank, and the second level gauge is electrically connected to the control mechanism;

[0020] The third liquid level gauge is installed inside the third dosing tank, and the third liquid level gauge is electrically connected to the control mechanism;

[0021] The control mechanism is used to receive and process the detection signals of the first level gauge, the second level gauge and the third level gauge, and to control the start or stop of the first metering pump, the second metering pump and the third metering pump.

[0022] As a preferred structure of this utility model, the papermaking wastewater treatment system further includes an alarm mechanism, which is electrically connected to the control mechanism. The alarm mechanism is used to issue an alarm, and the control mechanism is also used to control the activation or deactivation of the alarm mechanism.

[0023] As a preferred structure of this utility model, a first ball valve is provided on the pipeline between the first dosing tank and the first metering pump;

[0024] A second ball valve is installed on the pipeline between the second dosing tank and the second metering pump;

[0025] A third ball valve is installed on the pipeline between the third dosing tank and the third metering pump.

[0026] As a preferred structure of this utility model, a first filter component is provided on the pipeline between the first dosing tank and the first metering pump;

[0027] A second filter component is installed on the pipeline between the second dosing tank and the second metering pump;

[0028] A third filter component is provided on the pipeline between the third dosing tank and the third metering pump.

[0029] As a preferred structure of this utility model, the preliminary treatment mechanism includes a water collection tank and an acidification tank, and the acidification tank and the water collection tank are connected by pipelines.

[0030] As a preferred structure of this utility model, the preliminary treatment mechanism further includes an anaerobic tank, which is connected to the acidification tank via a pipeline, and the oxidation tank is connected to the anaerobic tank via a detection pipeline.

[0031] As a preferred structure of this utility model, the papermaking wastewater treatment system further includes a deep treatment mechanism, which is connected to the oxidation tank via a pipeline, and the final sedimentation tank is connected to the deep treatment mechanism via a pipeline.

[0032] As a preferred structure of this utility model, the deep treatment mechanism includes a coagulation reaction tank, a coagulation sedimentation tank, a Fenton reaction tank, and a Fenton sedimentation tank.

[0033] The coagulation reaction tank and the oxidation tank are connected by pipelines;

[0034] The coagulation sedimentation tank and the coagulation reaction tank are connected by pipelines;

[0035] The Fenton reaction tank and the coagulation sedimentation tank are connected by pipelines;

[0036] The Fenton sedimentation tank is connected to the Fenton reaction tank via a pipeline, and the final sedimentation tank is connected to the Fenton sedimentation tank via a pipeline.

[0037] As a preferred embodiment of this invention, the detection mechanism is a COD monitor.

[0038] The advantages of the above technical solution, compared with existing technologies, are as follows: In this papermaking wastewater treatment system, wastewater from the papermaking workshop first enters the preliminary treatment unit. This unit pre-treats the wastewater, removing some suspended impurities, adjusting its properties, and reducing the organic load. This alleviates the treatment pressure on the subsequent oxidation tank and improves the overall operating efficiency and treatment effect of the wastewater treatment system. After treatment in the preliminary treatment unit, the wastewater enters the oxidation tank through a detection pipeline. The detection unit on the pipeline monitors the COD concentration of the wastewater in real time and transmits the signal to the control unit. After processing the signal, the control unit controls the start or stop of the first, second, and third metering pumps based on the detected COD concentration. Specifically, when the detected COD concentration is lower than a preset value, the control unit starts the third metering pump and stops the first and second metering pumps, delivering an appropriate amount of polyaluminum ferric chloride solution from the third dosing tank to the oxidation tank, where a reaction occurs. When the COD concentration in the wastewater is low, replacing the ferrous sulfate solution and hydrogen peroxide solution in the first and second dosing tanks with polyaluminum ferric chloride solution in the third dosing tank reduces water treatment costs. Precise control of reagent dosage also lowers treatment costs and effectively reduces the COD concentration in the wastewater, ensuring that the wastewater meets discharge standards. This solves the problem of high costs associated with the existing Fenton process for treating papermaking wastewater, demonstrating significant economic and environmental benefits. When the detected COD concentration exceeds a preset value, the control mechanism starts the first and second metering pumps and shuts down the third metering pump, delivering appropriate amounts of ferrous sulfate solution and hydrogen peroxide solution from the first and second dosing tanks to the oxidation tank. The reaction in the oxidation tank effectively reduces the COD concentration in the wastewater, ensuring that the wastewater meets discharge standards.

[0039] The above description of the utility model is merely an overview of the technical solution of this application. In order to enable those skilled in the art to better understand the technical solution of this application and to implement it based on the description and drawings, and to make the above-mentioned objectives and other objectives, features and advantages of this application easier to understand, the following description is provided in conjunction with the specific embodiments and drawings of this application. Attached Figure Description

[0040] The accompanying drawings are only used to illustrate the principles, implementation methods, applications, features, and effects of specific embodiments of this application and other related content, and should not be considered as limitations on this application.

[0041] In the accompanying drawings of the instruction manual:

[0042] Figure 1 This is a schematic diagram of the papermaking wastewater treatment system described in a specific implementation method;

[0043] Figure 2This is a circuit connection diagram of the papermaking wastewater treatment system described in a specific embodiment;

[0044] Figure 3 This is a schematic diagram showing the connection between the first dosing tank and the oxidation tank in a specific implementation method;

[0045] Figure 4 This is a schematic diagram showing the connection between the second dosing tank and the oxidation tank in a specific implementation method;

[0046] Figure 5 This is a schematic diagram showing the connection between the third dosing tank and the oxidation tank in a specific implementation method.

[0047] The reference numerals used in the above figures are explained as follows:

[0048] 1. Catchment pool,

[0049] 2. Acidification tank,

[0050] 3. Anaerobic tank; 31. Testing pipeline; 32. Testing equipment.

[0051] 4. Oxidation tank; 41. First dosing tank; 42. First metering pump; 43. Second dosing tank; 44. Second metering pump; 45. Third dosing tank; 46. Third metering pump; 47. First level gauge; 48. Second level gauge; 49. Third level gauge; 410. First ball valve; 411. Second ball valve; 412. Third ball valve; 413. First filter element; 414. Second filter element; 415. Third filter element.

[0052] 5. Coagulation reaction tank,

[0053] 6. Coagulation sedimentation tank,

[0054] 7. Fenton reaction tank,

[0055] 8. Fenton sedimentation tank,

[0056] 9. Final settling tank,

[0057] 10. Control mechanism

[0058] 11. Alarm system. Detailed Implementation

[0059] To illustrate the possible application scenarios, technical principles, implementable specific solutions, and achievable objectives and effects of this application in detail, the following description, in conjunction with the listed specific embodiments and accompanying drawings, provides a detailed explanation. The embodiments described herein are merely illustrative of the technical solutions of this application and are therefore intended to limit the scope of protection of this application.

[0060] In this document, the term "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The term "embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment, nor does it specifically limit its independence or connection with other embodiments. In principle, in this application, as long as there are no technical contradictions or conflicts, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.

[0061] Unless otherwise defined, the technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the use of related terms herein is merely for the purpose of describing particular embodiments and is not intended to limit this application.

[0062] In the description of this application, the term "and / or" is used to describe the logical relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A exists, B exists, and A and B exist simultaneously. Additionally, the character " / " in this document generally indicates that the preceding and following objects have an "or" logical relationship.

[0063] In this application, 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 actual quantity, hierarchy or order relationship between these entities or operations.

[0064] Unless otherwise specified, the use of terms such as “comprising,” “including,” “having,” or other similar expressions in this application is intended to cover non-exclusive inclusion, which does not exclude the presence of additional elements in a process, method, or product that includes the stated elements, such that a process, method, or product that includes a list of elements may include not only those defined elements but also other elements not expressly listed, or elements inherent to such a process, method, or product.

[0065] Similar to the understanding in the Examination Guidelines, in this application, expressions such as "greater than," "less than," and "exceeding" are understood to exclude the stated number; expressions such as "above," "below," and "within" are understood to include the stated number. Furthermore, in the description of the embodiments in this application, "multiple" means two or more (including two), and similar expressions related to "multiple" are also understood in this way, such as "multiple groups" and "multiple times," unless otherwise explicitly specified.

[0066] In the description of the embodiments of this application, the space-related expressions used, such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "vertical," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," indicate the orientation or positional relationship based on the orientation or positional relationship shown in the specific embodiments or drawings. These expressions are only for the convenience of describing the specific embodiments of this application or for the reader's understanding, and do not indicate or imply that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application. Furthermore, in this context, it should be understood that when it is mentioned that an element is connected "on" or "below" another element, it can be directly connected not only to the other element "on" or "below," but also indirectly connected to the other element "on" or "below" through an intermediate element.

[0067] Unless otherwise expressly specified or limited, the terms "installation," "connection," "linking," "fixing," and "setting," as used in the description of the embodiments of this application, should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two components or the interaction between two components. For those skilled in the art to which this application pertains, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0068] Please see Figures 1 to 5 This embodiment relates to a papermaking wastewater treatment system, including:

[0069] The preliminary treatment unit is used to perform preliminary treatment on the wastewater from the papermaking workshop. The preliminary treatment unit is a structure that performs initial stage treatment on the wastewater discharged from the papermaking workshop. By pre-treating the wastewater through the preliminary treatment unit, some suspended impurities in the wastewater can be removed, the properties of the wastewater can be adjusted and the organic load can be reduced, thereby reducing the treatment pressure on subsequent treatment units such as oxidation pond 4 and improving the operating efficiency and treatment effect of the entire wastewater treatment system.

[0070] Oxidation tank 4, connected to the preliminary treatment unit via detection pipeline 31, receives the pre-treated wastewater. Oxidation, through a biological reaction process, transforms organic pollutants into harmless substances, while simultaneously achieving energy recovery and water reuse. In this process, organic matter in the wastewater is decomposed into smaller organic molecules, which are then sequentially oxidized and degraded by microorganisms into carbon dioxide and water. These are then converted into energy through redox reactions, achieving nitrogen and phosphorus removal. Oxidation tank 4 provides a site for deep oxidation treatment of wastewater, effectively removing organic matter and reducing COD concentration, laying the foundation for subsequent treatment and achieving compliant discharge.

[0071] The final settling tank 9 is connected to the oxidation tank 4 via pipeline; the final settling tank 9 is the tank where sedimentation treatment takes place in the wastewater process. In the final settling tank 9, suspended particles and other impurities in the wastewater settle to the bottom, separating the water from the impurities. The final settling tank 9 can completely remove suspended impurities from the treated wastewater, making the effluent clear and ensuring that the treated wastewater meets the discharge standards.

[0072] A detection mechanism 32 is installed on the detection pipeline 31. The detection mechanism 32 is used to detect the COD concentration of the wastewater within the detection pipeline 31. The detection mechanism 32 is a COD monitor, which detects the COD concentration of the wastewater within the detection pipeline 31 and transmits the detection signal to the control mechanism 10. The COD monitor can monitor the COD concentration of the wastewater in real time and accurately, providing a basis for the control mechanism 10 to control the dosage of chemicals, achieving precise dosing, avoiding reagent waste, and ensuring treatment effectiveness. In this embodiment, COD (Chemical Oxygen Demand) refers to the amount of oxygen consumed when reducing substances (mainly organic matter, but also including inorganic substances such as nitrites, sulfides, and ferrous salts) in water are oxidized by a strong oxidant under certain conditions. It is usually expressed as the equivalent oxygen mass concentration (mg / L).

[0073] The first dosing tank 41 is connected to the oxidation tank 4 via a pipeline. The first dosing tank 41 is used to provide ferrous sulfate solution to the oxidation tank 4. The first dosing tank 41 is used to store ferrous sulfate solution. The first dosing tank 41 is specifically used to store ferrous sulfate solution, which facilitates the management and addition of ferrous sulfate solution.

[0074] The first metering pump 42 is installed on the pipeline between the first dosing tank 41 and the oxidation tank 4; the first metering pump 42 can accurately control the amount of ferrous sulfate solution added, avoiding waste and increased costs due to excessive addition, or affecting the treatment effect due to insufficient addition, thereby achieving precise dosing and reducing treatment costs.

[0075] The second dosing tank 43 is connected to the oxidation tank 4 via a pipeline; wherein

[0076] The second dosing tank 43 is used to store hydrogen peroxide solution. The second dosing tank 43 is specifically used to store hydrogen peroxide solution, which facilitates the management and addition of hydrogen peroxide solution.

[0077] The second metering pump 44 is installed on the pipeline between the second dosing tank 43 and the oxidation tank 4. The second dosing tank 43 is used to provide hydrogen peroxide solution to the oxidation tank 4. The second metering pump 44 can accurately control the amount of hydrogen peroxide solution added, avoiding waste and increased costs due to excessive addition, or affecting the treatment effect due to insufficient addition, thereby achieving precise dosing and reducing treatment costs.

[0078] The third dosing tank 45 is connected to the oxidation tank 4 via a pipeline. The third dosing tank 45 is specifically used to store polyaluminum ferric chloride solution, facilitating its management and addition. Polyaluminum ferric chloride (PAFC) is a novel composite inorganic polymeric flocculant that combines the advantages of polyaluminum chloride (PAC) and polyferric sulfate (PFS). It exhibits strong flocculation ability and significant adsorption, bridging, and trapping effects on suspended particles and colloidal substances in water, forming large, dense flocs with rapid settling speed. During water treatment, PAFC releases high-valence polynuclear complex ions upon dissolving in water. Through charge neutralization (counteracting the negative charge of colloidal particles in water), adsorption bridging (connecting fine particles into large flocs), and trapping and sweeping (the flocs encapsulate suspended impurities during settling), pollutants in the water are agglomerated into larger flocs, which are ultimately removed through sedimentation or filtration, thus achieving water purification. It should be noted that the cost of polyaluminum ferric chloride solution is significantly lower than that of ferrous sulfate solution and hydrogen peroxide solution.

[0079] The third metering pump 46 is installed on the pipeline between the third dosing tank 45 and the oxidation tank 4. The third dosing tank 45 is used to provide polyaluminum ferric chloride solution to the oxidation tank 4. The third metering pump 46 can accurately control the amount of polyaluminum ferric chloride solution added, avoiding waste and increased costs due to excessive addition, or affecting the treatment effect due to insufficient addition, thereby achieving precise dosing and reducing treatment costs.

[0080] The system includes a control mechanism 10. The detection mechanism 32, the first metering pump 42, the second metering pump 44, and the third metering pump 46 are electrically connected to the control mechanism 10. The control mechanism 10 receives and processes the detection signals from the detection mechanism 32 and controls the start-up or shutdown of the first metering pump 42, the second metering pump 44, and the third metering pump 46. The control mechanism 10 controls and coordinates the entire wastewater treatment system. It automates the dosing process, precisely adjusting reagent dosage based on the actual wastewater conditions, avoiding errors from manual control and reagent waste, reducing treatment costs, and ensuring the stability of wastewater treatment results. The control mechanism 10 includes a PLC controller, a display screen, and multiple operation buttons, all electrically connected to the PLC controller.

[0081] Specifically, in the papermaking wastewater treatment system of this embodiment, the wastewater from the papermaking workshop first enters the preliminary treatment unit. This unit pre-treats the wastewater, removing some suspended impurities, adjusting its properties, and reducing the organic load. This alleviates the treatment pressure on the subsequent oxidation tank 4, improving the overall operating efficiency and treatment effect of the wastewater treatment system. After treatment by the preliminary treatment unit, the wastewater enters the oxidation tank 4 through the detection pipeline 31. The detection unit 32 on the detection pipeline 31 monitors the COD concentration of the wastewater in real time and transmits the signal to the control unit 10. After identification and processing, the control unit 10 controls the start or stop of the first metering pump 42, the second metering pump 44, and the third metering pump 46 based on the detected COD concentration. When the detected COD concentration is lower than a preset value, the control unit 10 controls the third metering pump 46 to start and controls the first metering pump 42 and the second metering pump 44 to stop, delivering an appropriate amount of polyaluminum ferric chloride solution from the third dosing tank 45 to the oxidation tank 4, where a reaction occurs. When the COD concentration in the wastewater is low, the ferrous sulfate solution and hydrogen peroxide solution in the first dosing tank 41 and the second dosing tank 43 are replaced with polyaluminum ferric chloride solution in the third dosing tank 45 to reduce water treatment costs. Precise control of reagent dosage also reduces treatment costs and effectively lowers the COD concentration in the wastewater, ensuring that the wastewater meets discharge standards. This solves the problem of high costs in existing Fenton processes for treating papermaking wastewater, demonstrating significant economic and environmental benefits. When the detected COD concentration exceeds a preset value, the control mechanism 10 starts the first metering pump 42 and the second metering pump 44 and shuts down the third metering pump 46, delivering appropriate amounts of ferrous sulfate solution and hydrogen peroxide solution from the first dosing tank 41 and the second dosing tank 43 to the oxidation tank 4. A reaction occurs in the oxidation tank 4 to effectively reduce the COD concentration in the wastewater, ensuring that the wastewater meets discharge standards. It should be noted that the preset value in this embodiment is 90 mg / L, but this preset value can be set according to actual conditions.

[0082] Optionally, in some embodiments, such as Figures 1 to 5As shown, the papermaking wastewater treatment system further includes a first level gauge 47, a second level gauge 48, and a third level gauge 49; the first level gauge 47 is disposed in the first dosing tank 41 and is electrically connected to the control mechanism 10; the second level gauge 48 is disposed in the second dosing tank 43 and is electrically connected to the control mechanism 10; the third level gauge 49 is disposed in the third dosing tank 45 and is electrically connected to the control mechanism 10; the control mechanism 10 is used to receive and process the detection signals of the first level gauge 47, the second level gauge 48, and the third level gauge 49, and to control the start or stop of the first metering pump 42, the second metering pump 44, and the third metering pump 46.

[0083] Specifically, the first level gauge 47, the second level gauge 48, and the third level gauge 49 are used to detect the liquid levels in the first dosing tank 41, the second dosing tank 43, and the third dosing tank 45, respectively, and transmit the liquid level signals to the control mechanism 10. After receiving the signals, the control mechanism 10 can control the start or stop of the corresponding first metering pump 42, second metering pump 44, and third metering pump 46 according to the liquid level. Among them, the first level gauge 47, the second level gauge 48, and the third level gauge 49 can monitor the solution storage in the first dosing tank 41, the second dosing tank 43, and the third dosing tank 45 in real time. When the liquid level is too low, the control mechanism 10 can promptly issue a signal to remind the operator to add solution, so as to avoid affecting the wastewater treatment process due to insufficient solution and ensure the continuous and stable operation of the system.

[0084] Optionally, in some embodiments, such as Figures 1 to 5 As shown, the papermaking wastewater treatment system also includes an alarm mechanism 11, which is electrically connected to the control mechanism 10. The alarm mechanism 11 is used to issue an alarm, and the control mechanism 10 is also used to control the activation or deactivation of the alarm mechanism 11. Specifically, when the control mechanism 10 receives low-level signals from the first level gauge 47, the second level gauge 48, and the third level gauge 49, it activates the alarm mechanism 11 to issue an alarm, reminding the operator to handle the situation promptly. The alarm mechanism 11 can promptly report low-level conditions in the first dosing tank 41, the second dosing tank 43, and the third dosing tank 45, allowing operators to quickly become aware and take appropriate measures to add solution, avoiding any impact on wastewater treatment efficiency or system malfunction due to delayed handling, thus improving the system's reliability and safety. The alarm mechanism 11 is an audible and visual alarm.

[0085] Optionally, in some embodiments, such as Figures 1 to 5As shown, a first ball valve 410 is installed on the pipeline between the first dosing tank 41 and the first metering pump 42; a second ball valve 411 is installed on the pipeline between the second dosing tank 43 and the second metering pump 44; and a third ball valve 412 is installed on the pipeline between the third dosing tank 45 and the third metering pump 46. A ball valve is a valve that opens and closes by rotating a ball 90° around the axis of the valve stem. The first ball valve 410, the second ball valve 411, and the third ball valve 412 are used to control the on / off state of their respective pipelines.

[0086] Among them, the ball valve has the characteristics of simple structure, rapid opening and closing, and good sealing performance. By controlling the opening and closing of the first ball valve 410, the second ball valve 411 and the third ball valve 412, the dosing pipeline can be easily inspected or the start and stop of dosing can be controlled, which improves the flexibility and maintainability of the system.

[0087] Optionally, in some embodiments, such as Figures 1 to 5 As shown, a first filter element 413 is installed on the pipeline between the first dosing tank 41 and the first metering pump 42; a second filter element 414 is installed on the pipeline between the second dosing tank 43 and the second metering pump 44; and a third filter element 415 is installed on the pipeline between the third dosing tank 45 and the third metering pump 46. The first filter element 413, the second filter element 414, and the third filter element 415 are used to filter impurities from the solution in their respective pipelines. These elements remove impurities from the solution, preventing them from entering the metering pump, avoiding blockage and damage, and ensuring the normal operation of all system components and the wastewater treatment effect. All three filter elements are filter screens.

[0088] Optionally, in some embodiments, such as Figures 1 to 5 As shown, the preliminary treatment facility includes a collection tank 1, an acidification tank 2, and an anaerobic tank 3. The acidification tank 2 is connected to the collection tank 1 via a pipeline, the anaerobic tank 3 is connected to the acidification tank 2 via a pipeline, and the oxidation tank 4 is connected to the anaerobic tank 3 via a detection pipeline 31. The main function of the collection tank 1 is to collect wastewater discharged from the paper mill, achieving centralized wastewater management and preventing secondary pollution caused by indiscriminate wastewater flow. The acidification tank 2 adjusts the pH value of the wastewater, keeping it within a suitable acid-base range for subsequent anaerobic treatment, and also decomposes some organic matter. The anaerobic tank 3 utilizes anaerobic microorganisms to decompose some large organic molecules in the wastewater into smaller molecules, reducing the organic load of the wastewater.

[0089] Optionally, in some embodiments, such as Figures 1 to 5As shown, the papermaking wastewater treatment system also includes a deep treatment mechanism, which is connected to the oxidation tank 4 via pipelines, and the final sedimentation tank 9 is also connected to the deep treatment mechanism via pipelines. The deep treatment mechanism further treats the wastewater after oxidation. This further treatment of the wastewater from the oxidation tank 4 more thoroughly removes organic matter and suspended impurities, further reduces COD concentration, ensures that the final discharged wastewater fully meets standards, and improves the quality of wastewater treatment.

[0090] Specifically, in this embodiment, such as Figures 1 to 5 As shown, the deep treatment mechanism includes a coagulation reaction tank 5, a coagulation sedimentation tank 6, a Fenton reaction tank 7, and a Fenton sedimentation tank 8; the coagulation reaction tank 5 is connected to the oxidation tank 4 via a pipeline; the coagulation sedimentation tank 6 is connected to the coagulation reaction tank 5 via a pipeline; the Fenton reaction tank 7 is connected to the coagulation sedimentation tank 6 via a pipeline; the Fenton sedimentation tank 8 is connected to the Fenton reaction tank 7 via a pipeline; and the final sedimentation tank 9 is connected to the Fenton sedimentation tank 8 via a pipeline.

[0091] The coagulation reactor 5 is a device used for wastewater treatment, its main function being to coagulate pollutants in the water. Coagulation refers to the process of agglomerating suspended particulate matter in water into larger particles through physical or chemical methods, making them easier to separate, filter, or biodegrade. The function of the coagulation reactor 5 is to disperse pollutants in the water into the reactor, then add coagulants and mixing equipment to mix and stir them, thereby causing them to agglomerate and facilitate subsequent treatment steps.

[0092] The coagulation sedimentation tank 6 is a physical purification tank. Its function is to remove suspended particulate matter in sewage through coagulation and sedimentation, thereby reducing sewage turbidity and organic matter concentration and achieving pretreatment effect.

[0093] The Fenton reactor 7 is an environmental engineering device used to treat organic pollutants in water. The Fenton reactor 7 uses the Fenton reaction to decompose and oxidize organic compounds, converting them into relatively harmless substances, thereby reducing the degree of pollution in the water.

[0094] The Fenton sedimentation tank 8 removes suspended solids from the water through natural sedimentation or coagulation sedimentation. The effluent from the Fenton reaction tank 7 flows by gravity to the Fenton sedimentation tank 8, where it is adjusted to neutral by adding alkali and then an appropriate amount of polyacrylamide is added for flocculation and sedimentation. It should be noted that the structure of the advanced treatment mechanism in this embodiment is not limited to this; those skilled in the art can select other suitable advanced treatment mechanisms based on the teachings of this embodiment.

[0095] Specifically, wastewater from the paper mill first enters the preliminary treatment unit, where it is collected in the collection tank 1, regulated in the acidification tank 2, and treated in the anaerobic tank 3 before entering the oxidation tank 4 through the detection pipeline 31. A COD monitor on the detection pipeline 31 continuously monitors the COD concentration of the wastewater and transmits the signal to the control unit 10. Based on the detected COD concentration, the control unit 10 controls the start or stop of the first metering pump 42, the second metering pump 44, and the third metering pump 46, causing the first dosing tank 41, the second dosing tank 43, and the third dosing tank 45 to respectively add appropriate amounts of ferrous sulfate solution, hydrogen peroxide solution, and polyaluminum ferric chloride solution to the oxidation tank 4, where a reaction occurs. When the detected COD concentration is lower than a preset value, the control unit 10 controls the start of the third metering pump 46 and the stop of the first and second metering pumps 44, delivering an appropriate amount of polyaluminum ferric chloride solution from the third dosing tank 45 to the oxidation tank 4, where a reaction occurs. When the COD concentration in the wastewater is low, the ferrous sulfate solution and hydrogen peroxide solution in the first dosing tank 41 and the second dosing tank 43 are replaced with polyaluminum ferric chloride solution in the third dosing tank 45 to reduce water treatment costs. Precise control of reagent dosage also reduces treatment costs and effectively lowers the COD concentration in the wastewater, ensuring that the wastewater meets discharge standards. This solves the problem of high costs in existing Fenton processes for treating papermaking wastewater, demonstrating significant economic and environmental benefits. When the detected COD concentration exceeds a preset value, the control mechanism 10 starts the first metering pump 42 and the second metering pump 44 and shuts down the third metering pump 46, delivering appropriate amounts of ferrous sulfate solution and hydrogen peroxide solution from the first dosing tank 41 and the second dosing tank 43 to the oxidation tank 4. A reaction occurs in the oxidation tank 4 to effectively reduce the COD concentration in the wastewater, ensuring that the wastewater meets discharge standards.

[0096] Wastewater treated in oxidation tank 4 enters the advanced treatment unit, and after being treated in sequence in coagulation reaction tank 5, coagulation sedimentation tank 6, Fenton reaction tank 7 and Fenton sedimentation tank 8, it enters final sedimentation tank 9 for final sedimentation.

[0097] Throughout the process, each level gauge monitors the solution level in the dosing tank in real time. When the level is too low, the control mechanism 10 controls the alarm mechanism 11 to issue an alarm. The first ball valve 410, the second ball valve 411, and the third ball valve 412 can control the opening and closing of the pipeline as needed. The first filter component 413, the second filter component 414, and the third filter component 415 filter the solution to ensure stable system operation. This not only effectively reduces the COD concentration in wastewater and ensures that the wastewater meets discharge standards, but also reduces treatment costs by precisely controlling reagent dosage and reducing waste. It solves the problem of high cost in the existing Fenton process for treating papermaking wastewater, and has significant economic and environmental benefits.

[0098] Finally, it should be noted that although the above embodiments have been described in the text and drawings of this application, this should not limit the scope of patent protection of this application. Any technical solutions that are based on the essential concept of this application and utilize the content described in the text and drawings of this application, resulting in equivalent structural or procedural substitutions or modifications, as well as the direct or indirect application of the technical solutions of the above embodiments to other related technical fields, are all included within the scope of patent protection of this application.

Claims

1. A papermaking wastewater treatment system, characterized in that, include: A preliminary treatment unit is used to perform preliminary treatment on wastewater from the paper mill. An oxidation tank, which is connected to the preliminary treatment unit via a detection pipeline. A final settling tank, which is connected to the oxidation tank via a pipeline; A detection mechanism is installed on the detection pipeline and is used to detect the COD concentration of wastewater in the detection pipeline; A first dosing tank is connected to the oxidation tank via a pipeline, and the first dosing tank is used to provide ferrous sulfate solution to the oxidation tank; A first metering pump is installed on the pipeline between the first dosing tank and the oxidation tank; The second dosing tank is connected to the oxidation tank via a pipeline; The second metering pump is installed on the pipeline between the second dosing tank and the oxidation tank. The second dosing tank is used to provide hydrogen peroxide solution to the oxidation tank. The third dosing tank is connected to the oxidation tank via a pipeline; The third metering pump is installed on the pipeline between the third dosing tank and the oxidation tank. The third dosing tank is used to supply polyaluminum ferric chloride solution to the oxidation tank. The system includes a detection mechanism electrically connected to the control mechanism, a first metering pump electrically connected to the control mechanism, a second metering pump electrically connected to the control mechanism, and a third metering pump electrically connected to the control mechanism. The control mechanism is used to receive and process the detection signals from the detection mechanism and to control the start-up or shutdown of the first metering pump, the second metering pump, and the third metering pump.

2. The papermaking wastewater treatment system according to claim 1, characterized in that: The papermaking wastewater treatment system also includes a first level gauge, a second level gauge, and a third level gauge; The first level gauge is installed inside the first dosing tank, and the first level gauge is electrically connected to the control mechanism; The second level gauge is installed inside the second dosing tank, and the second level gauge is electrically connected to the control mechanism; The third liquid level gauge is installed inside the third dosing tank, and the third liquid level gauge is electrically connected to the control mechanism; The control mechanism is used to receive and process the detection signals of the first level gauge, the second level gauge and the third level gauge, and to control the start or stop of the first metering pump, the second metering pump and the third metering pump.

3. The papermaking wastewater treatment system according to claim 2, characterized in that: The papermaking wastewater treatment system also includes an alarm mechanism, which is electrically connected to the control mechanism. The alarm mechanism is used to issue an alarm, and the control mechanism is also used to control the activation or deactivation of the alarm mechanism.

4. The papermaking wastewater treatment system according to claim 1, characterized in that: A first ball valve is installed on the pipeline between the first dosing tank and the first metering pump; A second ball valve is installed on the pipeline between the second dosing tank and the second metering pump; A third ball valve is installed on the pipeline between the third dosing tank and the third metering pump.

5. The papermaking wastewater treatment system according to claim 1 or 4, characterized in that: A first filter component is provided on the pipeline between the first dosing tank and the first metering pump; A second filter component is installed on the pipeline between the second dosing tank and the second metering pump; A third filter component is provided on the pipeline between the third dosing tank and the third metering pump.

6. The papermaking wastewater treatment system according to claim 1, characterized in that: The preliminary treatment unit includes a water collection tank and an acidification tank, and the acidification tank and the water collection tank are connected by pipelines.

7. The papermaking wastewater treatment system according to claim 6, characterized in that: The preliminary treatment unit also includes an anaerobic tank, which is connected to the acidification tank via a pipeline, and the oxidation tank is connected to the anaerobic tank via a detection pipeline.

8. The papermaking wastewater treatment system according to claim 1 or 7, characterized in that: The papermaking wastewater treatment system also includes a deep treatment mechanism, which is connected to the oxidation tank via a pipeline, and the final sedimentation tank is connected to the deep treatment mechanism via a pipeline.

9. The papermaking wastewater treatment system according to claim 8, characterized in that: The advanced treatment system includes a coagulation reaction tank, a coagulation sedimentation tank, a Fenton reaction tank, and a Fenton sedimentation tank. The coagulation reaction tank and the oxidation tank are connected by pipelines; The coagulation sedimentation tank and the coagulation reaction tank are connected by pipelines; The Fenton reaction tank and the coagulation sedimentation tank are connected by pipelines; The Fenton sedimentation tank is connected to the Fenton reaction tank via a pipeline, and the final sedimentation tank is connected to the Fenton sedimentation tank via a pipeline.

10. The papermaking wastewater treatment system according to claim 1, characterized in that: The testing institution is a COD monitor.

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