Electrochemical treatment device for high-salt wastewater difficult to biochemically degrade

Abstract

The utility model relates to an electrochemical treatment device for high-salt wastewater difficult to biochemically degrade. The electrochemical treatment device comprises a reaction box body, a gas-water module, a supporting piece, an electrode plate and a partition plate, wastewater to be treated enters through the water inlet in one side of the reaction area of the reaction box body, the liquid level of the wastewater rises slowly, the wastewater is stirred through air generated by the air-water module, inlet water can be mixed uniformly, meanwhile, the introduced air can fully dilute gas generated by subsequent electrochemistry, the concentration of harmful gas is reduced, and the treatment effect is improved. The water flow continues to upwards penetrate through the supporting piece, the wastewater flows and is electrolyzed between the electrode plates at the top of the supporting piece, and the reacted water flow overflows to a water storage area on the side and flows out through a water outlet of the reaction box body. And pollutants in the wastewater can be effectively treated at low cost.

Description

Technical Field

[0001] This application relates to the field of wastewater treatment, and in particular to an electrochemical treatment device for high-salt, recalcitrant wastewater. Background Technology

[0002] High-salinity wastewater is frequently generated in industrial production processes such as chemical plants and the extraction and processing of oil and natural gas. This type of wastewater contains a variety of substances, including salt, oil, heavy metals, and organic matter. The organic pollutants in high-salinity wastewater pose a significant environmental hazard. If biological treatment is used, the high concentration of salt inhibits microorganisms, requiring the cultivation and acclimatization of salt-tolerant microorganisms to ensure stable operation of the biological treatment process. Furthermore, the high salt concentration can easily lead to insufficient microbial activity or even microbial death, often resulting in poor effluent quality and excessive levels of COD, ammonia nitrogen, and total nitrogen.

[0003] Among commonly used advanced oxidation technologies, wet oxidation and ozone catalysis can reduce pollutant levels in high-salinity wastewater, but both suffer from high operating costs and poor removal efficiency. Utility Model Content

[0004] In view of this, this application proposes an electrochemical treatment device for high-salt, recalcitrant wastewater, which can treat pollutants in wastewater in a low-cost and effective manner.

[0005] According to one aspect of this application, an electrochemical treatment device for high-salt, recalcitrant wastewater is provided, comprising: a reaction chamber, a gas-water module, a support component, an electrode plate module, and a partition.

[0006] The reaction chamber is a hollow box structure. The partition is longitudinally arranged inside the reaction chamber, dividing the reaction chamber into a reaction zone and a water storage zone. The water inlet of the reaction chamber is located on one side of the reaction zone, and the water outlet of the reaction chamber is located on the other side of the water storage zone. The gas-water module, the support member, and the electrode plate module are all arranged in the reaction zone. The support member is laid horizontally in the reaction zone, and the top and bottom of the support member are connected. The gas-water module is arranged in the bottom space of the support member, and the electrode plate module is arranged in the top of the support member.

[0007] In one possible implementation, the air-water module includes: an aeration duct, a filter plate, a filter tube, and a filter head; the filter plate is horizontally arranged inside the reaction chamber, the filter head is inserted at the top of the filter tube, the filter tube is arranged at the bottom of the filter head, and the filter tube and the filter head pass through the filter plate, so that the top and bottom of the filter plate are connected; the aeration duct is horizontally laid at the bottom of the filter tube, one end of the aeration duct is adapted to be connected to the air supply end, and the aeration duct has air holes for gas overflow.

[0008] In one possible implementation, the filter tube is vertically arranged, with its bottom inlet end corresponding to the air hole, and the outlet end of the filter head is located at the top of the filter plate.

[0009] In one possible implementation, the number of filter heads and filter tubes is the same, and multiple filter heads are provided, with a preset distance between each filter head.

[0010] In one possible implementation, the bottom of the reaction zone is inclined, and the bottom of the reaction tank near the inlet is higher than the bottom of the reaction tank near the outlet.

[0011] In one possible implementation, there are multiple electrode plate modules, and a baffle is provided between each electrode plate module.

[0012] In one possible implementation, a power wire is provided on the top of the electrode plate module, the power wire being adapted for electrical connection with a power source.

[0013] In one possible implementation, the reaction chamber includes a reaction tank and a sealed enclosure, the sealed enclosure being fastened to the top of the reaction tank, the top projection of the sealed enclosure being able to cover the top projection of the reaction tank.

[0014] In one possible implementation, both the inlet and the outlet are located on the reaction tank, which is also provided with a circulating water inlet and a circulating water outlet. The circulating water inlet is located at a corresponding position in the reaction zone, and the circulating water outlet is located at a corresponding position in the water storage zone. The circulating water inlet and the circulating water outlet are connected by a pipeline.

[0015] In one possible implementation, the sealed enclosure is provided with a positive pressure vent and an air outlet, the positive pressure vent being located on one side of the reaction zone and the air outlet being located on one side of the water storage zone, and the positive pressure vent and the air outlet being connected to each other.

[0016] The beneficial effects of this application are as follows: The wastewater to be treated enters through the inlet on one side of the reaction zone of the reaction tank. The wastewater level rises slowly in the reaction zone, and the air generated by the air-water module agitates the wastewater, which can mix the influent. At the same time, the air introduced will also fully dilute the gas generated by subsequent electrochemistry, reducing the concentration of harmful substances. The water continues to flow upward through the support, and the wastewater flows between the electrode plates at the top of the support for electrolysis. The water after the reaction overflows to the water storage area on the side and flows out through the outlet of the reaction tank. According to the electrochemical treatment device for high-salt and difficult-to-biodegrade wastewater of this application, pollutants in wastewater can be treated in a low-cost and effective manner.

[0017] Other features and aspects of this application will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0018] The accompanying drawings, which are included in and form part of this specification, illustrate exemplary embodiments, features, and aspects of this application together with the specification and serve to explain the principles of this application.

[0019] Figure 1 This is a front perspective view of an electrochemical treatment apparatus for high-salt, recalcitrant wastewater according to an embodiment of this application;

[0020] Figure 2 This is a side sectional view of an electrochemical treatment apparatus for high-salt, recalcitrant wastewater according to an embodiment of this application;

[0021] Figure 3 This document illustrates a flowchart of a treatment method for an electrochemical treatment apparatus for high-salt, recalcitrant wastewater, according to an embodiment of this application. Detailed Implementation

[0022] Various exemplary embodiments, features, and aspects of this application will now be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings denote elements that have the same or similar functions. Although various aspects of the embodiments are shown in the drawings, they are not necessarily drawn to scale unless specifically indicated otherwise.

[0023] It should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "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 accompanying drawings. They are used only for the convenience of describing this application or to simplify the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0025] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.

[0026] Furthermore, to better illustrate this application, numerous specific details are provided in the following detailed embodiments. Those skilled in the art should understand that this application can be implemented without certain specific details. In some instances, methods, means, components, and circuits well-known to those skilled in the art have not been described in detail in order to highlight the main points of this application.

[0027] like Figure 1-2 As shown, the electrochemical treatment device for high-salt, recalcitrant wastewater includes: a reaction chamber 1, a gas-water module, a support 10, an electrode plate module 7, and a partition 16.

[0028] The reaction chamber 1 is a hollow chamber structure. The partition 16 is longitudinally arranged inside the reaction chamber 1, dividing the reaction chamber 1 into a reaction zone and a water storage zone. The water inlet 13 of the reaction chamber 1 is located on one side of the reaction zone, and the water outlet 9 of the reaction chamber 1 is located on the other side of the water storage zone. The gas-water module, the support 10, and the electrode plate module 7 are all arranged in the reaction zone. The support 10 is laid horizontally in the reaction zone, and the top and bottom of the support 10 are connected. The gas-water module is arranged in the bottom space of the support 10, and the electrode plate module 7 is arranged in the top of the support 10.

[0029] The reaction tank 1 consists of a reaction pool at the bottom and a sealed cover at the top. The pretreated high-salt wastewater flows into the reaction tank 1 through the inlet 13, and the water level rises slowly. Due to the obstruction of the filter plate 17, the water can only flow into the area above the filter plate 17 through the filter pipe 11. The water flows through the filter pipe 11 and the filter head 18, and then flows evenly into the aeration area above the filter plate 17 through the filter head 18. An aeration duct 12 is laid below the filter plate 17, and multiple air holes are opened on the filter plate 17. When the water flows into the aeration area, the air passing through the air holes will agitate the water flow and further mix the water. At the same time, the air introduced will also fully dilute the gas generated by subsequent electrochemistry, reducing the concentration of harmful gases. The water flow continues to rise and enters the electrode area at the top of the support member 10 through the water inlet between the support members 10. In the electrode area, electrode plate modules 7 of the same size and spacing are distributed. The electrode plate modules 7 are energized through the power wire 6 at the top of the electrode plate modules 7, so that the wastewater can flow between the electrode plate modules 7 for electrolysis. The electrode plate modules 7 are separated by baffles 8 to ensure that the electrode plate modules 7 do not interfere with each other.

[0030] The overflow of water flow through the baffle 8 flows to the water storage area, and through the circulating water outlet 15 provided on the reaction box body 1 corresponding to the water storage area, part of the water flow can be introduced into the circulating water inlet 14 beside the water inlet 13 through the circulating water pump, so that the wastewater can be fully treated multiple times. An outlet 9 is also provided on the reaction box body 1 corresponding to the water storage area, and the installation height of the outlet 9 is higher than that of the circulating water outlet 15. The outlet 9 is used to discharge the highly saline wastewater that has been fully treated and enter the subsequent treatment.

[0031] The closed cover on the top of the reaction tank can prevent the gas generated by the electrochemical reaction from flowing into the surrounding environment. A power cable pipe interface 3 and an on-line detector probe inlet 2 are provided above the closed cover, and positive pressure ventilation ports 4 and air outlets 5 are provided at both ends. Probes such as a thermometer, a pH meter, and a gas concentration detector can be inserted into the on-line detector probe inlet 2 for detecting the parameter changes in the reaction box body 1 in real time for timely adjustment; strong wind blows out at the positive pressure ventilation port 4, and the gases generated by the electrochemical reaction below, such as hydrogen and chlorine, are fully diluted by aeration through the aeration head and then quickly blown out to the air outlet 5 by the strong wind at the positive pressure ventilation port 4 to prevent the concentration of the mixed gases from being too high and having the risk of explosion.

[0032] The area between the filter plate 17 and the support member 10 is the aeration area, and the area on the top of the support plate where the motor module is provided is the electrode area.

[0033] In a possible implementation manner, the air-water module includes: an aeration air duct 12, a filter plate 17, a filter pipe 11, and a filter head 18; the filter plate 17 is horizontally arranged in the reaction box body 1, the filter head 18 is inserted at the top of the filter pipe 11, the filter pipe 11 is arranged at the bottom of the filter head 18, and the filter pipe 11 and the filter head 18 penetrate through the filter plate 17, so that the top and the bottom of the filter plate 17 are connected and arranged; the aeration air duct 12 is horizontally laid at the bottom of the filter pipe 11, one end of the aeration air duct 12 is suitable for connecting to the air supply end, and air holes are opened on the aeration air duct 12 for the overflow of gas.

[0034] The filter plate 17 is provided with installation holes, the bottom of the filter head 18 passes through the installation holes and is fixedly connected to the filter pipe 11 at the bottom by threads, and the size of the installation holes matches the size of the filter head 18, so that water flow will not enter the upper aeration area through the gap between the installation holes and the filter head 18.

[0035] The top view of the aeration air duct 12 has a "mountain" - shaped structure, provided with a horizontal pipe and several vertical pipes. The horizontal pipe is uniformly laid along the length or width direction of the reaction area, and the air holes are opened on the vertical pipes of the aeration air duct 12.

[0036] In a possible implementation manner, the filter pipe 11 is vertically arranged, and the inlet end at its bottom is arranged corresponding to the air holes, and the outlet end of the filter head 18 is arranged on the top of the filter plate 17.

[0037] In one possible implementation, the number of filter heads 18 and filter tubes 11 is the same, and multiple filter heads 18 are provided, with each filter head 18 not placed adjacent to another.

[0038] In one possible implementation, the bottom of the reaction zone is inclined, with the bottom of the reaction tank near the inlet 13 being higher than the bottom of the reaction tank near the outlet 9.

[0039] In one possible implementation, there are multiple electrode plate modules 7, and each electrode plate module 7 is provided with a baffle 8. The distance between the electrode plate module 7 and the adjacent baffle 8 is equal, so as to ensure that the reaction degree after the water flow electrode area is basically the same.

[0040] In one possible implementation, a power wire 6 is provided on the top of the electrode plate module 7, which is suitable for electrical connection with a power source.

[0041] In one possible implementation, the reaction chamber 1 includes a reaction pool and a sealed enclosure, the sealed enclosure being fastened to the top of the reaction pool, the top projection of the sealed enclosure being able to cover the top projection of the reaction pool.

[0042] In one possible implementation, both the inlet 13 and the outlet 9 are located on the reaction tank. The reaction tank is also equipped with a circulating water inlet 14 and a circulating water outlet 15. The circulating water inlet 14 is located at the corresponding position in the reaction zone, and the circulating water outlet 15 is located at the corresponding position in the water storage zone. The circulating water inlet 14 and the circulating water outlet 15 are connected by a pipeline.

[0043] In one possible implementation, the sealed enclosure is provided with a positive pressure vent 4 and an air outlet 5. The positive pressure vent 4 is located on one side of the reaction zone, and the air outlet 5 is located on one side of the water storage zone. The positive pressure vent 4 and the air outlet 5 are connected to each other.

[0044] Alternatively, in one feasible approach, the support member 10 is a rod-shaped structure, and multiple members are arranged side by side along the length or width of the reaction zone. It is sufficient that the support member 10 can support the electrode plate module 7 and the baffle 8 and allow water to flow through.

[0045] like Figure 3 As shown, the electrochemical treatment method for high-salt, recalcitrant wastewater described in this application involves pretreatment to remove fluoride ions and oily substances, followed by the introduction of the high-salt, recalcitrant wastewater into the electrochemical treatment device to remove pollutants such as COD, ammonia nitrogen, and total nitrogen from the high-salt wastewater, enabling the high-salt, recalcitrant wastewater to be discharged stably or proceed to the next stage of treatment.

[0046] The main reaction mechanisms in electrochemical processes are direct oxidation and indirect oxidation. Direct oxidation involves the reaction of H₂O and OH⁻ in solution. -In anodic discharge, adsorbed hydroxyl radicals are formed. These radicals then react with organic matter and ammonia nitrogen in high-salinity wastewater to produce carbon dioxide and nitrogen gas, which are then discharged. Indirect oxidation, on the other hand, generates strong oxidants such as hypochlorite and ozone through reactions between electrodes. These substances, when thoroughly mixed in the water, oxidize pollutants such as organic matter and ammonia nitrogen, producing carbon dioxide and nitrogen gas. The main chemical reactions are as follows:

[0047] 2NH3 + 6·OH = N2↑ + 6H2O

[0048] R+·OH=CO2↑+H2O+inorganic ions

[0049] SO4 2- -2e - +H₂O=SO₄ 2- +2H +

[0050] 2CI - -2e - =Cl2↑

[0051] Cl₂ + H₂O = HCl + HClO

[0052] 2NH4 + +3HCIO=N2↑+3H2O+5H + +3Cl -

[0053] 4OH - -4e - = 2H₂O + O₂↑

[0054] HS - →S+H + +2e -

[0055] 2S + 3H₂O → S₂O₃ 2- +6H + +4e -

[0056] 2HS - →S2 2- +2H + +2e -

[0057] S2 2- →S+2e -

[0058] 3HS - →S3 2- +3H + +4e -

[0059] HS - +4H₂O→SO₄ 2- +9H + +8e -

[0060] S2O3 2- +O 2 →SO4 2-

[0061] Electrochemical oxidation has the dual function of catalyzing chemical reactions and electron migration, resulting in high reaction efficiency and the ability to remove pollutants to the extreme. The electrochemical oxidation process does not require the addition of chemical reagents, meets emission requirements, and within a suitable concentration range, its equipment investment is lower than that of technologies such as wet oxidation.

[0062] Example 1: The high-salinity wastewater from a chemical plant had the following characteristics: COD 766 mg / L, pH 6.34, and conductivity 106.2 mS / cm. After treatment for 3 hours using the electrochemical device described in this application, the wastewater quality was as follows: COD 48 mg / L, pH 8.87, and conductivity 102.2 mS / cm.

[0063] Example 2: The waste alkaline solution from a chemical plant had the following characteristics: COD 6500 mg / L, sulfide 700 mg / L, pH 13.34, and conductivity 91.0 mS / cm. After treatment for 6 hours using the electrochemical device described in this application, the water quality was as follows: COD 1055 mg / L, sulfide 0 mg / L, pH 13.27, and conductivity 88.4 mS / cm.

[0064] Example 3: The caprolactam wastewater from a chemical plant had the following characteristics: COD 89 mg / L, pH 7.31, and conductivity 11.58 ms / cm. After treatment for 30 minutes using the electrochemical device described in this application, the wastewater quality was as follows: COD 22 mg / L, pH 8.03, and conductivity 11.32 ms / cm.

[0065] This application effectively reduces various pollutant indicators in high-salinity wastewater, solving the problem of difficult degradation of pollutants such as COD, ammonia nitrogen, and total nitrogen. By introducing a filter head for water distribution, the influent to the reaction device is made more uniform, thereby improving reaction efficiency. The addition of an aeration and positive pressure ventilation system increases the flow rate of the treated water, while small air bubbles provide a certain degree of scrubbing effect on the reaction plates, preventing scale buildup and extending plate lifespan. Furthermore, the waste gas generated during the electrochemical treatment process is fully diluted and discharged, ensuring the safety and stability of the electrochemical process. The electrochemical treatment device involved in this method has advantages such as high reaction efficiency, stable pollutant removal effect, and low secondary pollution.

[0066] It should be noted that although this application has been used as an example to describe an electrochemical treatment device for high-salt, recalcitrant wastewater, those skilled in the art will understand that this application is not limited thereto. In fact, users can flexibly set various parameters according to their personal preferences and / or actual application scenarios, as long as the design is reasonable.

[0067] In this way, the wastewater to be treated enters through the inlet on one side of the reaction zone of the reaction tank. The wastewater level rises slowly, and the air generated by the air-water module agitates the wastewater, which can mix the influent. At the same time, the air introduced will also fully dilute the gas generated by subsequent electrochemistry, reducing the concentration of harmful substances. The water continues to flow upward through the support, and the wastewater flows between the electrode plates at the top of the support for electrolysis. The reacted water overflows to the side storage area and flows out through the outlet of the reaction tank. According to the electrochemical treatment device for high-salt and difficult-to-biodegrade wastewater of this application, pollutants in wastewater can be treated in a low-cost and effective manner.

[0068] The various embodiments of this application have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. An electrochemical treatment device for high-salt, recalcitrant wastewater, characterized in that, include: The reaction chamber, gas-water module, support components, electrode plate module, and partition plate; The reaction chamber is a hollow box structure. The partition is arranged longitudinally inside the reaction chamber. The reaction chamber is divided into a reaction zone and a water storage zone. The water inlet of the reaction chamber is located on one side of the reaction zone, and the water outlet of the reaction chamber is located on one side of the water storage zone. The gas-water module, the support member, and the electrode plate module are all disposed within the reaction zone. The support member is laid horizontally within the reaction zone, with its top and bottom connected. The gas-water module is disposed within the bottom space of the support member, and the electrode plate module is disposed at the top of the support member.

2. The electrochemical treatment device for high-salt, recalcitrant wastewater according to claim 1, characterized in that, The air-water module includes: aeration pipe, filter plate, filter tube and filter head; The filter plate is horizontally arranged inside the reaction chamber, the filter head is inserted at the top of the filter tube, the filter tube is arranged at the bottom of the filter head, and the filter tube and the filter head pass through the filter plate, so that the top and bottom of the filter plate are connected. The aeration pipe is laid horizontally at the bottom of the filter tube. One end of the aeration pipe is suitable for connecting to the air supply end. The aeration pipe has air holes for gas overflow.

3. The electrochemical treatment device for high-salt, recalcitrant wastewater according to claim 2, characterized in that, The filter tube is set vertically, and its bottom inlet end is set corresponding to the air hole. The outlet end of the filter head is set at the top of the filter plate.

4. The electrochemical treatment device for high-salt, recalcitrant wastewater according to claim 3, characterized in that, The number of filter heads and filter tubes is the same, and multiple filter heads are provided, with a preset distance between each filter head.

5. The electrochemical treatment device for high-salt, recalcitrant wastewater according to claim 4, characterized in that, The bottom of the reaction zone is inclined, and the bottom of the reaction tank near the inlet is higher than the bottom of the reaction tank near the outlet.

6. The electrochemical treatment apparatus for high-salinity, recalcitrant wastewater according to any one of claims 1-4, characterized in that, There are multiple electrode plate modules, and each electrode plate module is provided with a baffle.

7. The electrochemical treatment device for high-salt, recalcitrant wastewater according to claim 6, characterized in that, The top of the electrode plate module is provided with a power wire, which is suitable for electrical connection with a power source.

8. The electrochemical treatment device for high-salinity, recalcitrant wastewater according to any one of claims 1-4, characterized in that, The reaction chamber includes a reaction tank and a sealed cover. The sealed cover is fastened to the top of the reaction tank, and the top projection of the sealed cover can cover the top projection of the reaction tank.

9. The electrochemical treatment device for high-salt, recalcitrant wastewater according to claim 8, characterized in that, Both the inlet and the outlet are located on the reaction tank. The reaction tank is also provided with a circulating water inlet and a circulating water outlet. The circulating water inlet is located at a corresponding position in the reaction zone, and the circulating water outlet is located at a corresponding position in the water storage zone. The circulating water inlet and the circulating water outlet are connected by a pipeline.

10. The electrochemical treatment device for high-salinity, recalcitrant wastewater according to claim 8, characterized in that, The sealed enclosure is provided with a positive pressure vent and an air outlet. The positive pressure vent is located on one side of the reaction zone, and the air outlet is located on one side of the water storage zone. The positive pressure vent and the air outlet are connected to each other.

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