A high nitrogen and phosphorus-containing wastewater treatment system

Abstract

A kind of high nitrogen-containing phosphorus wastewater treatment system, including pH adjusting pool, primary reaction pool, sedimentation tank, secondary reaction pool, air floatation tank, filter tank, electrochemical reaction tank and clear water tank in series in proper order;The electrochemical reaction tank includes electrochemical device, electrochemical device is assembled by multiple independent box, it is arranged in a row in the form of '' one '' character, the cavity in each box forms a reaction chamber, and the connecting side of adjacent box is equipped with communicating port, after sealing connection of adjacent box, communicating port of adjacent box is interconnected, and exchange membrane is installed between the communicating port of adjacent box.This utility model directly degrades organic pollutants by electrode reaction, long-term operation cost is lower than traditional technology, achieves the simultaneous recycling of nitrogen and phosphorus, and helps to realize the sustainable development and resource recovery of wastewater treatment.

Description

Technical Field

[0001] This utility model relates to a wastewater treatment technology system, specifically a wastewater treatment system for high nitrogen and phosphorus content wastewater. Background Technology

[0002] With the unprecedented speed of agricultural, industrial, and urbanization processes, the demand for water resources in various sectors is increasing daily, while the discharge of nitrogen and phosphorus-containing wastewater is also rising sharply. In agriculture, the excessive use of chemical fertilizers has resulted in farmland runoff carrying large amounts of nitrogen and phosphorus. In the process of industrialization, many industrial enterprises generate wastewater rich in nitrogen and phosphorus during production, which is discharged directly without effective treatment. Rapid urbanization and high population concentration have led to a significant increase in the discharge of domestic sewage, which also contains considerable amounts of nitrogen and phosphorus.

[0003] The continuous discharge of such massive amounts of nitrogen and phosphorus-containing wastewater into natural water bodies has exacerbated the problem of eutrophication. The consequences of eutrophication severely impact the balance of aquatic ecosystems. Algae thrive in eutrophic waters, leading to overgrowth and widespread algal blooms or red tides. These algae not only consume large amounts of dissolved oxygen but also block sunlight, hindering photosynthesis in aquatic plants and disrupting the food chain structure of the entire aquatic ecosystem. Large numbers of fish die due to oxygen depletion and food chain disruption, resulting in a sharp decline in aquatic biodiversity. More critically, eutrophic waters seriously threaten the sustainable use of water resources, impacting the safety of drinking water sources and posing a significant challenge to ecological security.

[0004] Given the aforementioned severe situation, the development of efficient nitrogen and phosphorus-containing wastewater treatment technologies is urgently needed, as it is of vital practical significance for maintaining ecological balance and ensuring a sustainable water supply.

[0005] However, some current technologies for treating nitrogen- and phosphorus-containing wastewater have numerous drawbacks. For example, the traditional wastewater treatment method used in patent CN208980466U, while capable of removing nitrogen and phosphorus from wastewater to some extent, often suffers from low treatment efficiency. Due to its complex and lengthy process, treating the same volume of wastewater requires a significant amount of time, making it difficult to meet the ever-increasing demand for wastewater treatment. Simultaneously, treatment costs remain high, requiring substantial investment in everything from the chemical reagents needed to equipment operation and maintenance. Furthermore, the operation is extremely complex, demanding high levels of expertise from operators, increasing labor costs and operational difficulty. In addition, these traditional methods often generate large amounts of chemical sludge during wastewater treatment. This chemical sludge contains various complex chemical components, posing significant challenges to its subsequent treatment and disposal. It not only requires specialized treatment facilities and technologies but may also cause secondary pollution to the environment. In summary, existing wastewater treatment methods have significant shortcomings in treating nitrogen- and phosphorus-containing wastewater, and there is an urgent need for a more efficient, energy-saving, environmentally friendly wastewater treatment technology that can achieve simultaneous nitrogen and phosphorus recovery. Utility Model Content

[0006] This invention proposes a wastewater treatment system for high-nitrogen and phosphorus-containing wastewater, aiming to achieve rapid treatment of wastewater through a high-concentration nitrogen and phosphorus industrial wastewater treatment system, while simultaneously utilizing an electrochemical device to achieve the simultaneous recovery and reuse of nitrogen and phosphorus. The specific details are as follows:

[0007] A high-nitrogen and high-phosphorus wastewater treatment system includes a pH adjustment tank, a primary reaction tank, a sedimentation tank, a secondary reaction tank, an air flotation tank, a filtration tank, an electrochemical reaction tank, and a clear water tank connected in series. The electrochemical reaction tank includes an electrochemical device, which is composed of multiple independent boxes arranged in a straight line. Each box has a chamber forming a reaction chamber. The connecting side of adjacent boxes is provided with a communication port. After the adjacent boxes are connected, the communication ports of the adjacent boxes are interconnected. An exchange membrane is installed between the communication ports of the adjacent boxes.

[0008] In this embodiment, five boxes are provided. From left to right, a cation exchange membrane, an anion exchange membrane, a cation exchange membrane, and a gas permeation membrane are sequentially sealed between the connecting ports of adjacent boxes, so that the boxes form an anode chamber, an acid production chamber, a desalination chamber, a cathode chamber, and an absorption chamber from left to right. An anode plate is provided in the anode chamber, a cathode plate is provided in the cathode chamber, a water inlet is provided in the cathode chamber, a water outlet is provided in the desalination chamber, a first exhaust port is provided at the top of the cathode chamber, and a second exhaust port is provided at the top of the anode chamber.

[0009] In this embodiment, a flange is provided on the connecting side of the box, and adjacent boxes are connected to each other through the flange.

[0010] In this embodiment, an acid-base dosing device is installed at the reagent inlet of the pH adjustment tank; an automatic dosing device is installed at the reagent inlet of the primary reaction tank and the secondary reaction tank; and an activated carbon filtration device is installed in the filtration tank.

[0011] In this embodiment, a grid and a microporous filter membrane are sequentially installed on the wastewater inlet of the pH adjustment tank.

[0012] In this embodiment, the automatic dosing device includes a coagulant dosing device and a flocculant dosing device.

[0013] In this embodiment, the flotation tank is equipped with a flotation device.

[0014] In this embodiment, a stirring system is provided in the pH adjustment tank, the primary reaction tank, the secondary reaction tank, and the flotation tank.

[0015] In this embodiment, the filter element in the activated carbon filtration device is provided with an activated carbon filter and a quartz sand support layer in sequence from the inlet to the outlet.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. The electrochemical device of this application adopts a modular structure, in which the chambers in each box form a reaction chamber. After the adjacent boxes are sealed and connected, the solutions in the adjacent boxes can selectively permeate through the exchange membrane to achieve electrolysis. The modular structure facilitates the cleaning of precipitates generated during the reaction in the reaction chamber and facilitates the transportation and installation of the device.

[0018] 2. This application utilizes a pre-treatment process involving a pH adjustment tank, a primary reaction tank, a sedimentation tank, a secondary reaction tank, an air flotation tank, and a filtration tank to pretreat nitrogen- and phosphorus-containing wastewater. This removes large inorganic particles, heavy metals, and other impurities, reducing the competitive adsorption and treatment difficulty of subsequent electrochemical devices. It can efficiently treat wastewater and recover nitrogen and phosphorus elements. Moreover, the electrochemical process requires little or no chemical reagents, saving costs. Furthermore, the use of electrochemical devices offers several advantages: firstly, the electrochemical reaction is fast, achieving the expected treatment effect in a short time; secondly, high-salt and heavy-metal wastewater generates large amounts of nitrogen and phosphorus during the electrochemical process, which this application can further recover from. Compared to traditional methods, its shift from "treating pollutants" to "recovering resources" aligns better with the needs of a circular economy and sustainable development.

[0019] In summary, this invention directly degrades organic pollutants through electrode reactions, has lower long-term operating costs than traditional technologies, and achieves simultaneous recovery and utilization of nitrogen and phosphorus, which contributes to the sustainable development of wastewater treatment and resource recycling. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall process of this utility model;

[0021] Figure 2 This is a schematic diagram of the internal structure of the electrochemical device of this utility model;

[0022] Figure 3 This is a schematic diagram of the external structure of the electrochemical device of this utility model;

[0023] Figure 4 This is a schematic diagram of the flange of the electrochemical device of this utility model;

[0024] In the diagram: 1. Power supply; 2. Wire; 3. Cation exchange membrane; 4. Anode plate; 5. Anion exchange membrane; 6. Anode chamber; 7. Acid production chamber; 8. Desalination chamber; 9. Cathode chamber; 10. Absorption chamber; 11. Cathode plate; 12. Gas permeation membrane; 13. Inlet; 14. Outlet; 15. First vent; 16. Second vent; 17. Flange. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present utility model, and not all of them. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0026] like Figures 1 to 4 As shown, a high-nitrogen and phosphorus wastewater treatment system includes a pH adjustment tank, a primary reaction tank, a sedimentation tank, a secondary reaction tank, a flotation tank, a filtration tank, an electrochemical reaction tank, and a clear water tank connected in series. The pH adjustment tank is equipped with an acid / alkali dosing device at its reagent inlet. The primary and secondary reaction tanks are equipped with automatic dosing devices at their reagent inlets. The filtration tank contains an activated carbon filtration device. The wastewater inlet of the pH adjustment tank is equipped with a grid and a microporous membrane arranged sequentially along the water flow direction. The automatic dosing device includes a coagulant dosing device and a flocculant dosing device. The flotation tank contains a flotation device, and the pH adjustment tank, primary reaction tank, secondary reaction tank, and flotation tank are all equipped with a stirring system.

[0027] like Figure 2 , 3As shown in Figure 4, the electrochemical reaction cell includes an electrochemical device, which consists of five independent boxes arranged in a straight line. Each box contains a chamber forming a reaction chamber. Connecting ports are provided on the connecting sides of adjacent boxes. After the adjacent boxes are sealed together, their connecting ports are interconnected. Exchange membranes are installed between the connecting ports of adjacent boxes. These exchange membranes include a cation exchange membrane 3, an anion exchange membrane 5, and a gas permeation membrane 12. In this embodiment, cation exchange membranes are sequentially sealed between the connecting ports of adjacent boxes from left to right. The ion exchange membrane 3, anion exchange membrane 5, cation exchange membrane 3, and gas permeation membrane 12 form, from left to right, an anode chamber 6, an acid production chamber 7, a desalination chamber 8, a cathode chamber 9, and an absorption chamber 10. An anode plate 4 is installed in the anode chamber 6, and a cathode plate 11 is installed in the cathode chamber 9. The anode plate 4 and cathode plate 11 are connected to the positive and negative terminals of the power supply 1 via wires 2, respectively. The desalination chamber 8 has an outlet 14, and the cathode chamber 9 has an inlet 13. A first exhaust port 15 is located at the top of the cathode chamber 9, and a second exhaust port 16 is located at the top of the anode chamber 6. Specifically, the dimensions of the anode chamber, acid production chamber, desalination chamber, cathode chamber, and absorption chamber are all length (1–1.5 meters) × width (1–1.5 meters) × height (0.4–1.0 meters). In this embodiment, the anode plate is made of titanium plate, platinum plate or porous carbon material, and the outer surface of the anode plate is coated with iridium oxide layer, ruthenium oxide layer or cerium oxide layer. The cathode plate is made of stainless steel mesh or carbon-based material. Since the anode plate and cathode plate adopt the above-mentioned stable electrodes, the device can simultaneously realize N / P recovery, which greatly improves efficiency and reduces energy consumption.

[0028] like Figure 4 As shown, a flange 17 is provided on the connecting side of the box body. The flange 17 has multiple through holes. The flanges 17 of adjacent boxes are connected to each other by screws installed in the through holes. Sealing rings can also be provided on the connecting surfaces of adjacent boxes to improve the sealing effect.

[0029] Embodiments of this utility model:

[0030] Nitrogen- and phosphorus-containing wastewater is filtered through a screen and a microporous membrane before being introduced into a pH adjustment tank. The screen and microporous membrane are used to trap colloidal particles and suspended particulates in the wastewater. In the pH adjustment tank, a stirring system is activated to ensure uniform mixing of the wastewater. Based on the real-time reading of the pH meter, appropriate chemicals are added using an acid-base dosing device. In this embodiment, the chemicals refer to acid-base neutralizing agents, including sulfuric acid, hydrochloric acid, calcium hydroxide, calcium hydroxide, or sodium carbonate, etc., to adjust the pH value of the wastewater to an optimal value, usually neutral or slightly alkaline, to facilitate subsequent sedimentation and biological reactions. The adjusted wastewater is then introduced into a primary reaction tank, where a stirring system is activated to maintain uniform mixing. Flocculants and coagulants are added using an automatic dosing device to promote the sedimentation or biodegradation of pollutants. In this embodiment, polyaluminum chloride (PAC) and polyferric sulfate (PFS) are used as coagulants, and polyacrylamide (PAM) is used as a flocculant. The pH value and temperature in the reaction tank are monitored in real time to ensure suitable biological reaction conditions. Wastewater from the primary reaction tank is introduced into a sedimentation tank, and the sludge recovery system is activated to collect and transfer the sediment. The liquid level and sludge concentration in the sedimentation tank are monitored in real time to ensure effective settling and prevent sludge overflow. The supernatant from the sedimentation tank is introduced into the secondary reaction tank, and the stirring system in the secondary reaction tank is activated to maintain uniform mixing of the wastewater. Additional flocculants and coagulants are added through an automatic dosing device to further promote the sedimentation or biodegradation of pollutants. The pH and temperature in the reaction tank are monitored in real time to ensure suitable biological reaction conditions.

[0031] Wastewater from the secondary reaction tank is introduced into the dissolved air flotation (DAF) tank. In the DAF tank, the DAF machine and stirring system are activated to release microbubbles, which adsorb tiny suspended solids and grease. The foam and sludge collection in the DAF tank are monitored to ensure effective pollutant removal. The effluent from the DAF tank is then introduced into a filtration tank. In the filtration tank, the filtration system is activated to remove pollutants through an activated carbon filter.

[0032] The effluent from the filter tank is introduced into the electrochemical device through inlet 13. The wastewater first enters the cathode chamber 9, then the electrochemical device is started and connected to power supply 1. Parameters are adjusted according to the characteristics of the wastewater and the treatment objectives, and voltage 2 is regulated. On the anode plate 4, pollutants in the wastewater undergo an oxidation reaction, generating electrons that are released into the circuit. The cation exchange membrane 3 allows cations to pass through while blocking anions and undissolved substances, maintaining charge balance between chambers. On the cathode plate 11, electrons are received, leading to a reduction reaction involving the deposition of metal ions or the reduction of organic matter. The anion exchange membrane 5 allows anions to pass through while blocking cations and undissolved substances. The gas permeation membrane 12 allows ammonia permeation. The treated wastewater is discharged through outlet 14 on the desalination chamber 8. High concentrations of wastewater generated in the absorption chamber 10... The waste is discharged through the first exhaust port 15; the anode of the electrochemical device is dissolved in situ. or Phosphate precipitate is generated in the cathode chamber, achieving the purpose of phosphorus resource recovery; Phosphate is introduced into nitrogen recovery tank and phosphorus recovery tank for treatment, respectively.

[0033] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A wastewater treatment system for high nitrogen and phosphorus content, characterized in that, It includes a pH adjustment tank, a primary reaction tank, a sedimentation tank, a secondary reaction tank, an air flotation tank, a filtration tank, an electrochemical reaction tank, and a clear water tank connected in series. The electrochemical reaction tank includes an electrochemical device, which is composed of multiple independent boxes arranged in a straight line. Each box has a chamber that forms a reaction chamber. The connecting side of adjacent boxes is provided with a communication port. After the adjacent boxes are sealed and connected, the communication ports of the adjacent boxes are interconnected. An exchange membrane is installed between the communication ports of the adjacent boxes.

2. The high-nitrogen and phosphorus wastewater treatment system according to claim 1, characterized in that, The chamber is provided with five compartments. From left to right, a cation exchange membrane, an anion exchange membrane, a cation exchange membrane, and a gas permeation membrane are sequentially sealed between the connecting ports of adjacent compartments, so that the compartments form an anode chamber, an acid production chamber, a desalination chamber, a cathode chamber, and an absorption chamber from left to right. An anode plate is provided in the anode chamber, a cathode plate is provided in the cathode chamber, a water inlet is provided in the cathode chamber, a water outlet is provided in the desalination chamber, a first exhaust port is provided at the top of the cathode chamber, and a second exhaust port is provided at the top of the anode chamber.

3. The high-nitrogen and phosphorus wastewater treatment system according to claim 1, characterized in that, The box body is provided with a flange on the connecting side, and adjacent boxes are connected to each other through the flange.

4. The high-nitrogen and phosphorus wastewater treatment system according to any one of claims 1 to 3, characterized in that, The pH adjustment tank is equipped with an acid-base dosing device at the reagent inlet; the primary and secondary reaction tanks are equipped with automatic dosing devices at the reagent inlets; and the filtration tank is equipped with an activated carbon filtration device.

5. The high-nitrogen and phosphorus wastewater treatment system according to claim 4, characterized in that, The wastewater inlet of the pH adjustment tank is equipped with a grid and a microporous filter membrane in sequence.

6. The high-nitrogen and phosphorus wastewater treatment system according to claim 4, characterized in that, The automatic dosing device includes a coagulant dosing device and a flocculant dosing device.

7. The high-nitrogen and phosphorus wastewater treatment system according to claim 4, characterized in that, The flotation tank is equipped with a flotation device.

8. The high-nitrogen and phosphorus wastewater treatment system according to claim 4, characterized in that, The pH adjustment tank, primary reaction tank, secondary reaction tank, and flotation tank are all equipped with stirring systems.

9. A high-nitrogen and phosphorus wastewater treatment system according to claim 4, characterized in that, The filter element in the activated carbon filtration device consists of an activated carbon filter and a quartz sand support layer arranged sequentially from the inlet to the outlet.

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