An electronic electroplating wastewater treatment and reuse system and method

Abstract

The present application relates to electroplating wastewater treatment field, especially to a kind of electronic electroplating wastewater treatment reuse system and method.A kind of electronic electroplating wastewater treatment reuse system, including reaction tank and pH adjusting mechanism, the reaction tank is used to accommodate wastewater, the pH adjusting mechanism is set to reaction tank top, the pH adjusting mechanism is used to adjust the pH of wastewater according to demand, further including: several pH sensors, for measuring the pH of wastewater in reaction tank, and generate pH data, the reaction tank is divided into several regions from top to bottom, and each region is provided with at least one pH sensor;Data processing module: the data processing module is used to receive the pH data of each region, and the pH difference data of adjacent two subareas is calculated.A kind of electronic electroplating wastewater treatment reuse method, including the following steps: S1: wastewater is input into reaction tank……Solve the problem of inaccurate reagent dosage when adjusting the pH of cyanide-containing chromium electroplating wastewater.

Description

Technical Field

[0001] This invention relates to the field of electroplating wastewater treatment, and in particular to an electronic electroplating wastewater treatment and reuse system and method. Background Technology

[0002] The main pollutants in electroplating wastewater are metal ions, followed by acids, alkalis, oxides and oil residues from the pretreatment of the substrate, and organic matter generated from the use of surfactants and organic materials. However, the primary pollutants in electroplating are heavy metal ions, acids, alkalis, and organic matter. Wastewater containing heavy metals mainly comes from the electroplating and passivation processes, and is generally acidic. Its composition is related to the plating metal (common plating metals include chromium, zinc, nickel, cadmium, copper, and silver). Wastewater containing these metals is generated during the cleaning of plated parts. Cyanide-containing wastewater comes from the cleaning stage of cyanide electroplating. The cleaning wastewater after degreasing is alkaline, while the wastewater from the cyanide removal process is acidic, mainly containing sulfuric acid, hydrochloric acid, hydrofluoric acid, etc., as shown in the attached image. Figure 1 The diagram illustrates the process flow for conventional electroplating wastewater treatment.

[0003] The invention patent with application number 201610516273.0 discloses a treatment process for cyanide and chromium-containing electroplating wastewater, characterized by the following steps: (1) passing the cyanide and chromium-containing electroplating wastewater through an iron-carbon micro-electrolysis reactor; (2) adjusting the pH to 9-11, then adding sodium hypochlorite, reacting for 10-60 minutes, then controlling the pH value to 4-6, reacting for 10-60 minutes, then adding flocculant for flocculation treatment, and then performing precipitation treatment; (3) adjusting the pH value to 10-12, then adding sodium hypochlorite to make the oxidation-reduction potential of the treated wastewater above 350mV, reacting for 30-60 minutes; then adding activated carbon, reacting for 10-60 minutes; (4) adding flocculant, and then precipitating; This invention can remove harmful substances from wastewater, especially removing ferricyanide complexes that are difficult to remove by conventional methods, and adsorbing heavy metals, ensuring that the various indicators of the cyanide and chromium-containing electroplating wastewater meet the standards after treatment.

[0004] Taking the treatment of mixed cyanide-chromium plating wastewater as an example, the wastewater first needs to have cyanide removed under alkaline conditions within a specific range. Then, under acidic conditions within a specific range, hexavalent chromium is reduced to trivalent chromium, which is less toxic. Finally, the wastewater is adjusted to alkaline conditions again, and flocculants are added to complete the sedimentation. When treating large volumes of wastewater, acid or alkali is added to adjust the pH value. However, the pH value measured in the wastewater is lagging, lacking dynamic assessment. Therefore, the amount of acid or alkali added is unclear, potentially leading to over-addition and substandard wastewater discharge. A technology is needed to dynamically control the pH value of mixed cyanide-chromium plating wastewater based on the wastewater treatment steps. Summary of the Invention

[0005] This invention provides a system and method for treating and reusing electronic electroplating wastewater, which can solve the problem of inaccurate reagent dosage when adjusting the pH value of cyanide-chromium electroplating wastewater.

[0006] To solve the above-mentioned technical problems, this application provides the following technical solution:

[0007] An electronic electroplating wastewater treatment and reuse system includes a reaction tank and a pH adjustment mechanism. The reaction tank is used to contain wastewater, and the pH adjustment mechanism is located above the reaction tank. The pH adjustment mechanism is used to adjust the pH value of the wastewater as needed. The system also includes:

[0008] Several pH sensors are used to measure the pH value of the wastewater in the reaction tank and generate pH data. The reaction tank is divided into several areas from top to bottom, and each area is equipped with at least one pH sensor.

[0009] Data processing module: The data processing module is used to receive pH value data for each region and calculate the pH value difference between two adjacent zones;

[0010] The pH adjustment mechanism includes an acid adjustment channel and an alkali adjustment channel. The acid adjustment channel is used to add acid to the reaction tank to adjust the pH value of the wastewater, and the alkali adjustment channel is used to add alkali to the reaction tank to adjust the pH value of the wastewater. Both the acid adjustment channel and the alkali adjustment channel are equipped with electronic water valves. The electronic water valves are used to control the opening and closing of the acid adjustment channel and the alkali adjustment channel to add acid and alkali to the wastewater tank, as well as the rate of addition of acid or alkali, when receiving control commands from the data processing module. The electronic water valves have several settings to adjust the instantaneous flow rate of adding acid or alkali.

[0011] The reagent addition channel is used to add sodium sulfite and flocculant to the wastewater when the pH value of the wastewater reaches a preset value;

[0012] The data processing module issues corresponding control commands based on the pH value of each zone and the pH difference between adjacent zones. If the pH value of the second-to-last zone from top to bottom does not reach the preset value, the data processing module controls the electronic water valve to add acid or alkali at the fastest speed. If the pH value of the second-to-last zone reaches the preset value, and the pH difference between the bottom two adjacent zones does not reach the threshold, the data processing module controls the electronic water valve to add acid or alkali at the slowest speed. When the pH difference between the bottom two zones reaches the threshold, the data processing module controls the electronic water valve to close, and at the same time, the data processing module controls the reagent addition channel to add reagent to the wastewater.

[0013] Basic principle and beneficial effects: There are multiple pH sensors, which are set in each section of the reaction tank from top to bottom. The pH adjustment mechanism is set at the top of the reaction tank and is used to adjust the pH value in the tank according to the needs. That is, the original hexavalent chromium is reduced to trivalent chromium, and then the trivalent chromium is converted into chromium hydroxide flocculent precipitate. Sodium sulfite and flocculant are added to make the flocculent precipitate aggregate into large particles for easy filtration.

[0014] Since the reaction tank, as a wastewater treatment tank, typically has a large capacity, when adding acid or alkali to adjust the pH, the upper layer solution may have already reached the preset pH value, but the pH value of the lower layer solution may not have changed. This solution intelligently manages the valves of the alkali and acid adjustment channels. Using data measured by pH sensors at multiple locations, it dynamically adjusts the pH value of various parts of the reaction tank, controlling the addition rate and dosage of alkali and acid to save time and reduce manual labor costs. Furthermore, the intelligent control method makes the control more precise, reducing dosage errors during manual addition, saving raw materials and time, and solving the problem of inaccurate reagent dosage when adjusting the pH value of cyanide-chromium electroplating wastewater.

[0015] Furthermore, the reaction tank is divided into an upper region, a middle region, and a lower region.

[0016] Beneficial effects: The reaction tank is divided into three equal parts from top to bottom according to its height: the upper, middle and lower regions. Data is collected at multiple points, providing more data samples for convenient later analysis. The three-layered region prevents data sample concentration and reflects the pH details of each part of the reaction tank as much as possible, providing a basis for subsequent pH adjustment by adding acid or alkali.

[0017] Furthermore, the data processing module receives pH data measured by pH sensors in the upper, middle, and lower layers, respectively, and calculates the first difference between the pH data in the upper and middle layers, and the second difference between the pH data in the middle and lower layers. The electronic water valve has several speed settings, including high-speed, medium-speed, and low-speed. When the pH value in the upper layer does not reach the preset pH value, or when the pH value in the upper layer reaches the preset pH value but the first difference does not reach the first threshold, the data processing module issues a high-speed continuous feeding command, and the electronic water valve controls the corresponding acid adjustment. The acid or alkali adjustment channel continuously adds acid or alkali to the reaction tank at high speed. When the pH value in the middle layer region does not reach the preset pH value, the first difference data exceeds the first threshold, and the second difference data does not reach the second threshold, the data processing module issues a medium-speed continuous feeding command. The electronic water valve controls the corresponding acid or alkali adjustment channel to continuously add acid or alkali to the reaction tank at medium speed. When the pH value in the middle layer region reaches the preset pH value and the second difference data does not reach the second threshold, the data processing module issues a low-speed continuous feeding command. The electronic water valve controls the corresponding acid or alkali adjustment channel to continuously add acid or alkali to the reaction tank at low speed. When the second difference data reaches the second threshold, the electronic valve is closed.

[0018] Beneficial effects: Data-driven evaluation and control, based on the pH difference between each layer, determines the rate of adding acid or alkali, saving time and making the dosage more precise.

[0019] Furthermore, it also includes an inlet pipe and an outlet pipe, both of which are connected to the reaction tank. The inlet pipe is used to input wastewater into the reaction tank, and the outlet pipe is used to discharge the supernatant after adding flocculant into the reaction tank.

[0020] Beneficial effects: The establishment of inlet and outlet pipes makes wastewater treatment a process line, namely input, treatment, and output, realizing intelligent and process-oriented management.

[0021] Furthermore, it also includes an ion exchange column, which is located inside the drain pipe near the reaction tank. The ion exchange resin inside the ion exchange column can be a strong acid or a weak acid cation exchange resin, used to remove metal cations from the supernatant.

[0022] Beneficial effects: It absorbs metal ions in the supernatant, reducing the metal ion content in the discharged supernatant and meeting emission standards.

[0023] Furthermore, an electric three-way diversion regulating valve is installed at the outlet of the water outlet pipe. The outlet of the water outlet pipe is connected to the inlet of the electric three-way diversion regulating valve. One outlet of the electric three-way diversion regulating valve is connected to a dedicated sewage pipe, and the other outlet of the electric three-way diversion regulating valve is connected to the reaction tank. A metal ion detection mechanism is also installed in the water outlet pipe between the ion exchange column and the electric three-way diversion regulating valve to detect the metal ion content in the supernatant. If the metal ion content does not exceed the preset value, the electric three-way diversion regulating valve opens the outlet connected to the dedicated sewage pipe. If the metal ion content exceeds the preset value, the electric three-way diversion regulating valve opens the outlet connected to the reaction tank.

[0024] Beneficial effects: If the metal ion content in the supernatant to be discharged exceeds the standard, it will be returned to the reaction tank; if the content is within the standard range, it will be discharged into a dedicated sewage pipe, and the treatment will be completed.

[0025] Furthermore, it also includes a stirring mechanism, which is disposed within the reaction tank.

[0026] Beneficial effects: It makes the reaction in the reaction tank more complete and accelerates the reaction efficiency.

[0027] A method for treating and reusing electronic electroplating wastewater includes the following steps:

[0028] S1: Input wastewater into the reaction tank;

[0029] S2: Removes cyanide from wastewater and reduces hexavalent chromium to trivalent chromium;

[0030] S3: Add sodium sulfite and flocculant to the wastewater to produce precipitate;

[0031] S4: Pass the supernatant through an ion exchange column to remove metal ions from the supernatant;

[0032] S5: Detect the metal ion content in the supernatant after passing through the ion exchange column, and determine whether the treated supernatant should be sent to a dedicated sewage discharge channel or returned to the reaction tank based on the detection results.

[0033] Furthermore, the precipitate generated in step S3 is filtered under pressure at 2-4 MPa, and the filtrate is returned to the reaction tank for recycling.

[0034] Furthermore, the flocculant is one of polyacrylamide, PAC, and PFC. Attached Figure Description

[0035] Figure 1 A schematic diagram of an electronic electroplating wastewater treatment and reuse system;

[0036] Figure 2A flowchart illustrating the steps of a method for treating and reusing electronic electroplating wastewater;

[0037] Figure 3 This is a schematic diagram of the permeation treatment tank in Example 2;

[0038] Figure 4 A schematic diagram of the reaction chamber in Example 2.

[0039] The diagram in the instruction manual is labeled as follows: osmosis treatment tank 100, third anode 101, third cathode 102, DC power supply 103, bipolar membrane 104, anion exchange membrane 105, cation exchange membrane 106, alkali outlet 1071, acid outlet 1072, and reflux outlet 1073. Detailed Implementation

[0040] The following detailed description illustrates the specific implementation method:

[0041] Example 1 is attached. Figure 1 As shown,

[0042] An electronic electroplating wastewater treatment and reuse system includes a reaction tank and a pH adjustment mechanism. The reaction tank is divided into three zones from top to bottom: an upper zone, a middle zone, and a lower zone. The height of each zone is one-third of the total height of the reaction tank after deducting the sedimentation height, ensuring that the sedimentation height during subsequent reactions does not submerge the pH sensor subsequently installed in the lower zone. The reaction tank is used to contain wastewater. The pH adjustment mechanism is located above the reaction tank and is used to adjust the pH value of the wastewater as needed. The system also includes:

[0043] Three pH sensors are used to measure the pH value of the wastewater in the reaction tank and generate pH data. At least one pH sensor is installed in each area; the upper area is placed in the upper left, the middle area in the middle, and the lower area in the lower right. The pH sensor is an online pH meter P535.

[0044] Data Processing Module: The data processing module uses an i3 12110f CPU and related components to complete data processing and issue relevant instructions. The module receives pH data measured by pH sensors in the upper, middle, and lower layers, respectively, and calculates the first difference between the upper and middle layer pH data, and the second difference between the middle and lower layer pH data.

[0045] The pH adjustment mechanism includes an acid adjustment channel and an alkali adjustment channel. The acid adjustment channel is used to add acid to the reaction tank to adjust the pH value of the wastewater, and the alkali adjustment channel is used to add alkali to the reaction tank to adjust the pH value of the wastewater. Both the acid and alkali adjustment channels are equipped with electronic water valves. The electronic water valves are used to control the opening and closing of the acid and alkali adjustment channels to add acid and alkali to the wastewater tank and the speed of adding acid or alkali when receiving control commands from the data processing module. The electronic water valves have several settings to adjust the instantaneous flow rate of adding acid or alkali. The electronic water valves have several settings including high speed, medium speed and low speed. In this embodiment, the degree of valve opening is used as the speed evaluation standard, that is, the electronic water valve is 100% open as high speed, the electronic water valve is 60% open as medium speed, and the electronic water valve is 20% open as low speed.

[0046] In this embodiment, the first and second difference data are selected as 0.3. The preset value of the pH value of the wastewater under acidic or alkaline reaction conditions is the average value of the selectable range. Taking the preset value of 2.5 when the selectable range of pH is 2-3 (wastewater pH is reduced by adding acid under alkaline conditions) as an example, if the pH value of the upper layer does not reach 2.5, acid is added at high speed; if the pH value of the upper layer reaches 2.5 but the pH value of the middle layer does not reach 2.8, acid is added at medium speed to reduce the pH value of the wastewater; if the pH value of the middle layer reaches 2.5 but the pH value of the bottom layer does not reach 2.8, acid is added at low speed to reduce the pH value of the wastewater; if the pH value of the bottom layer reaches 2.8, the acid adding valve is closed, indicating that the pH value of the wastewater has been successfully adjusted. The system also includes a stirring mechanism, which is set in the reaction tank. The stirring mechanism is used to rotate when adding acid or alkali to adjust the pH value or when adding reagents, to accelerate the fusion of wastewater with the added acid, alkali or reagents and improve the reaction fusion efficiency.

[0047] The reagent addition channel is used to add sodium sulfite when the pH of the wastewater is between 8.2 and 10.4. If the pH of the wastewater is outside this range, the pH adjustment mechanism first adjusts the pH to within the range. When the preset value is reached, if the pH in the lower layer reaches 9.0 (wastewater adjusted from acidic to alkaline) or 9.6 (wastewater pH reduced from strongly alkaline), the pH adjustment is successful. Then, sodium sulfite is added at a concentration eight times the total cyanide concentration (obtained through sampling tests) for aeration. After the reaction, the pH of the wastewater is adjusted to 2-3, meaning that under acidic conditions, sodium sulfite reduces hexavalent chromium in the wastewater to trivalent chromium. After reduction, flocculant polyacrylamide is added to precipitate chromium ions as a compound. The precipitation time is 2 hours, and the precipitate is then recovered by pressure filtration.

[0048] It also includes an inlet pipe and an outlet pipe, both of which are connected to the reaction tank. The inlet pipe is used to input wastewater into the reaction tank, and the outlet pipe is used to discharge the supernatant after adding flocculant into the reaction tank.

[0049] It also includes an ion exchange column, which is located inside the drain pipe near the reaction tank. The ion exchange resin inside the ion exchange column can be a strong acid or a weak acid cation exchange resin, used to remove metal cations from the supernatant.

[0050] The outlet of the water outlet pipe is equipped with an electric three-way diversion regulating valve. The outlet of the water outlet pipe is connected to the inlet of the electric three-way diversion regulating valve. One outlet of the electric three-way diversion regulating valve is connected to a dedicated sewage pipe, and the other outlet of the electric three-way diversion regulating valve is connected to the reaction tank. A metal ion detection mechanism is also installed in the water outlet pipe between the ion exchange column and the electric three-way diversion regulating valve to detect the metal ion content in the supernatant. If the metal ion content does not exceed the preset value, the electric three-way diversion regulating valve opens the outlet connected to the dedicated sewage pipe. If the metal ion content exceeds the preset value, the electric three-way diversion regulating valve opens the outlet connected to the reaction tank.

[0051] A method for treating and reusing electronic electroplating wastewater includes the following steps:

[0052] S1: Input wastewater into the reaction tank;

[0053] S2: Removes cyanide from wastewater and reduces hexavalent chromium to trivalent chromium;

[0054] S3: Add sodium sulfite and flocculant to the wastewater to produce precipitate; the precipitate is filtered at 2-4 MPa, the filtrate is returned to the reaction tank, and the precipitate is recycled.

[0055] S4: Pass the supernatant through an ion exchange column to remove metal ions from the supernatant;

[0056] S5: Detect the metal ion content in the supernatant after passing through the ion exchange column, and determine whether the treated supernatant should be sent to a dedicated sewage discharge channel or returned to the reaction tank based on the detection results.

[0057] Example 2

[0058] The difference between Example 2 and Example 1 is as follows: (See attached) Figure 3As shown, the permeation treatment tank 100 is divided into an anode chamber, a first reaction chamber, a second reaction chamber, and a metal ion chamber by a sequentially arranged anode, an anion exchange membrane 105, a bipolar membrane 104, a cation exchange membrane 106, an anion exchange membrane 105, and a cathode. The anode and the second cathode are electrically connected to the positive and negative terminals of a DC power supply 103, respectively. The bipolar membrane 104 is composed of an anion exchange layer and a cation exchange layer. The first reaction chamber has an alkali outlet 1071, and the second reaction chamber has an acid outlet 1072.

[0059] Reaction chamber: as attached Figure 4 As shown, the reaction tank has three holes at both ends, two of which are connected to the alkali drain port 1071 and acid drain port 1072 on the first reaction chamber, respectively. Several venting holes are also provided above the reaction tank. The reflux port 1073 on the reaction tank is connected to the reflux ports 1073 of the first and second reaction chambers via pipes. The reflux port 1073 on the reaction tank is also connected to the inlet pipe, allowing the solution to enter the reaction pool for subsequent reactions. Valves are installed on all pipes. At the start of pretreatment, wastewater is introduced into the first and second reaction chambers respectively. When the metal ion content reaches the national emission standard, the solution in the reaction tank is introduced into the reaction pool through the inlet pipe for subsequent treatment.

[0060] To treat wastewater containing a large amount of carbonate ions and prevent the generation of carbon dioxide gas in the second reaction chamber, which could cause membrane burn-in of the bipolar membrane 104, the following method is adopted: H2O between the anion and cation membrane composite layers of the bipolar membrane 104 dissociates into H+ and OH-, which pass through the anion and cation membranes respectively, serving as H+ and OH- ion sources. Hydrogen ions permeate through the cation membrane layer of the bipolar membrane 104 into the second reaction tank. Metal ions, under the influence of an electric field, enter the metal ion chamber. Initially, the pH value of the second reaction tank is adjusted so that the reaction between carbonate and hydrogen ions only produces bicarbonate ions. The compound formed by the bicarbonate ions is then introduced into the reaction tank through the acid outlet 1072. Hydroxide ions permeate through the anion membrane of the bipolar membrane 104 into the first reaction tank, while metal ions... Under the influence of an electric field, the solution enters the anode chamber, where metal ions are separated. The solution in the first reaction tank is alkaline. The liquid in the first reaction chamber is connected to the second reaction chamber through the alkali drain port 1071. The liquid in the first reaction chamber reacts fully with the liquid in the second reaction chamber, generating carbon dioxide which is discharged, thus removing carbonate ions. The solution then flows back to the first and second reaction chambers through the holes on the reaction tank. The solution is now alkaline and returns to the second reaction tank, further consuming newly generated hydrogen ions and preventing the formation of carbon dioxide in the second reaction chamber, which could burn the bipolar membrane 104. Furthermore, there is no need to add new alkaline substances to the second reaction chamber to adjust the pH, reducing the use of alkaline substances. The permeation treatment tank 100 and the reaction tank are used to remove carbonate ions from the wastewater and simultaneously perform the initial separation of metal and non-metal ions in the wastewater. Once the metal ion content drops to the national standard, the liquid in the first and second reaction chambers is discharged through the reaction tank to the reaction tank for further treatment, further reducing the metal ion content in the wastewater.

[0061] The above are merely embodiments of the present invention. The invention is not limited to the fields covered by these embodiments. Commonly known structures and characteristics in the solutions are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are able to access all existing technologies in that field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can, under the guidance of this application, improve and implement this solution in combination with their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention. These should also be considered within the scope of protection of the present invention, and will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. An electronic electroplating wastewater treatment and reuse system, comprising a reaction tank and a pH adjustment mechanism, wherein the reaction tank is used to contain wastewater, and the pH adjustment mechanism is disposed above the reaction tank, and the pH adjustment mechanism is used to adjust the pH value of the wastewater as needed, characterized in that, Also includes: Several pH sensors are used to measure the pH value of the wastewater in the reaction tank and generate pH data. The reaction tank is divided into several areas from top to bottom, and each area is equipped with at least one pH sensor. Data processing module: The data processing module is used to receive pH value data for each region and calculate the pH value difference between two adjacent zones; The pH adjustment mechanism includes an acid adjustment channel and an alkali adjustment channel. The acid adjustment channel is used to add acid to the reaction tank to adjust the pH value of the wastewater, and the alkali adjustment channel is used to add alkali to the reaction tank to adjust the pH value of the wastewater. Both the acid adjustment channel and the alkali adjustment channel are equipped with electronic water valves. The electronic water valves are used to control the opening and closing of the acid adjustment channel and the alkali adjustment channel to add acid and alkali to the wastewater tank, as well as the rate of addition of acid or alkali, when receiving control commands from the data processing module. The electronic water valves have several settings to adjust the instantaneous flow rate of adding acid or alkali. The reagent addition channel is used to add sodium sulfite and flocculant to the wastewater when the pH value of the wastewater reaches a preset value; The data processing module issues corresponding control commands based on the pH value of each zone and the pH difference between adjacent zones. If the pH value of the second-to-last zone from top to bottom does not reach the preset value, the data processing module controls the electronic water valve to add acid or alkali at the fastest speed. If the pH value of the second-to-last zone reaches the preset value, and the pH difference between the bottom two adjacent zones does not reach the threshold, the data processing module controls the electronic water valve to add acid or alkali at the slowest speed. When the pH difference between the bottom two zones reaches the threshold, the data processing module controls the electronic water valve to close, and at the same time, the data processing module controls the reagent addition channel to add reagents to the wastewater. The reaction tank is divided into an upper region, a middle region, and a lower region; The data processing module receives pH data measured by pH sensors in the upper, middle, and lower layers, respectively. It calculates the first difference between the upper and middle layer pH data, and the second difference between the middle and lower layer pH data. The electronic water valve has several speed settings, including high-speed, medium-speed, and low-speed. When the pH value in the upper layer does not reach the preset pH value, or when the pH value in the upper layer reaches the preset pH value but the first difference does not reach the first threshold, the data processing module issues a high-speed continuous feeding command. The electronic water valve then controls the corresponding acid adjustment channel. The acid or alkali adjustment channel continuously adds acid or alkali to the reaction tank at high speed. If the pH value in the middle layer region does not reach the preset pH value, the first difference data exceeds the first threshold, and the second difference data does not reach the second threshold, the data processing module issues a medium-speed continuous feeding command. The electronic water valve controls the corresponding acid or alkali adjustment channel to continuously add acid or alkali to the reaction tank at medium speed. When the pH value in the middle layer region reaches the preset pH value and the second difference data does not reach the second threshold, the data processing module issues a low-speed continuous feeding command. The electronic water valve controls the corresponding acid or alkali adjustment channel to continuously add acid or alkali to the reaction tank at low speed. When the second difference data reaches the second threshold, the electronic valve is closed.

2. The electronic electroplating wastewater treatment and reuse system according to claim 1, characterized in that: It also includes an inlet pipe and an outlet pipe, both of which are connected to the reaction tank. The inlet pipe is used to input wastewater into the reaction tank, and the outlet pipe is used to discharge the supernatant after adding flocculant into the reaction tank.

3. The electronic electroplating wastewater treatment and reuse system according to claim 2, characterized in that: It also includes an ion exchange column, which is located in the outlet pipe near the reaction tank. The ion exchange resin in the ion exchange column can be a strong acid or a weak acid cation exchange resin, used to remove metal cations from the supernatant.

4. The electronic electroplating wastewater treatment and reuse system according to claim 3, characterized in that: The outlet of the liquid outlet pipe is equipped with an electric three-way diversion regulating valve. The outlet of the liquid outlet pipe is connected to the inlet of the electric three-way diversion regulating valve. One outlet of the electric three-way diversion regulating valve is connected to a dedicated sewage pipe, and the other outlet of the electric three-way diversion regulating valve is connected to the reaction tank. A metal ion detection mechanism is also installed in the liquid outlet pipe between the ion exchange column and the electric three-way diversion regulating valve to detect the metal ion content in the supernatant. If the metal ion content does not exceed the preset value, the electric three-way diversion regulating valve opens the outlet connected to the dedicated sewage pipe. If the metal ion content exceeds the preset value, the electric three-way diversion regulating valve opens the outlet connected to the reaction tank.

5. The electronic electroplating wastewater treatment and reuse system according to claim 1, characterized in that: It also includes a stirring mechanism, which is disposed within the reaction tank.

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