A device and method for integrated enrichment and detection of heavy metal ions in wastewater

Abstract

The application discloses a kind of enrichment detection integration device and method of heavy metal ion in wastewater, including shell frame, steel structure top frame fixed on the top of shell frame and coagulation tank installed in the inside of shell frame, four mutually isolated cavities are provided in coagulation tank, cavity is used to accommodate equal amount of electroplating wastewater and corresponding heavy trapping agent;Left and right side cavities are arranged between the shell frame and the coagulation tank, two backflushing reagent storage assemblies are installed in left side cavity and right side cavity respectively, each backflushing reagent storage assembly is used to store a flocculating agent or coagulant aid.The application uses the cooperation of multiple-pipe dosing assembly and backflushing reagent storage assembly, and is automatically controlled by control box, realizes simultaneous, equal injection of flocculating agent or coagulant aid into each cavity of coagulation tank, solves the problem of time asynchronization caused by manual sequential dosing.

Description

Technical Field

[0001] This invention relates to the field of heavy metal ion detection technology in wastewater, specifically to an integrated device and method for the enrichment and detection of heavy metal ions in wastewater. Background Technology

[0002] When detecting the enrichment of heavy metal ions in electroplating wastewater, a multi-unit coagulation electric agitator is required. Different heavy metal chelating agents, such as sodium thiram, small molecule piperazine chelating agents, light red polymeric chelating agents, and yellowish-brown polymeric chelating agents, are added to each stirring chamber of the multi-unit coagulation electric agitator. After stirring, an equal volume of 2.5% polyaluminum chloride solution is added. After obvious colloidal suspension appears, a 0.1% polyacrylamide solution is added, and the stirring speed is adjusted to 50 to 80 rpm to avoid breaking up the flocs. Then, the supernatant of each group of water samples is taken, and the residual concentration of each heavy metal in the supernatant is detected to determine the treatment effect of different heavy metal chelating agents. The detection of residual concentration in the supernatant can be carried out in conjunction with an electrochemical workstation, using anodic stripping voltammetry to detect trace heavy metal ions in the supernatant of electroplating wastewater after flocculation and precipitation, so as to evaluate the heavy metal enrichment effect. In this heavy metal enrichment detection scheme for electroplating wastewater, the multi-unit electric coagulation mixer plays a core role in solution mixing and reaction-aided coagulation. Although a control experiment design has been implemented with differentiated settings for each group of heavy metal precipitating agents and equal addition of flocculants and coagulants, it still relies on manual addition of flocculants and coagulants by operators. Manual addition makes it difficult to ensure the synchronicity and consistency of the addition of each group of agents. Specifically, the detection requires that flocculants and coagulants be added to each mixing chamber at the same time and in equal amounts to eliminate the interference of differences in addition time and dosage on the flocculation and sedimentation effect. However, during manual operation, the... Personnel need to add chemicals to multiple stirring beakers sequentially. Even if the action is rapid, there will inevitably be a time difference between the addition of chemicals to some chambers and the reaction with the wastewater, while some chambers have not yet been added. This results in inconsistent reaction start times for each group, violating the single variable principle of the control experiment. Furthermore, manual measurement of chemicals relies on instruments such as graduated cylinders and pipettes, which are susceptible to deviations from theoretical values ​​due to operator skill and visual errors. This directly alters the colloid formation rate and floc formation effect, making it impossible to make cross-comparisons of the subsequent heavy metal concentration detection results in the supernatant. Summary of the Invention

[0003] The purpose of this invention is to provide an integrated device and method for the enrichment and detection of heavy metal ions in wastewater. Four backflushing storage units each contain a flocculant or coagulant aid. Different heavy metal ions are added one by one to the corresponding cavities of the coagulation tank and mixed by a multi-shaft coagulation and stirring assembly. The multi-pipe dosing assembly is then activated via a control box, simultaneously injecting equal amounts of the flocculant or coagulant aid from the corresponding backflushing storage units into each cavity of the coagulation tank. The multi-shaft coagulation and stirring assembly stirs at low speed and enriches the flocculated material to form flocs. After sedimentation, the supernatant of each group of water samples is collected. Trace heavy metal ions in the supernatant of the electroplating wastewater after flocculation and sedimentation are detected using an electrochemical workstation and anodic stripping voltammetry, thereby solving the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: an integrated device for enrichment and detection of heavy metal ions in wastewater, comprising an outer shell frame, a steel structure top frame fixed to the top of the outer shell frame, and a coagulation tank installed inside the outer shell frame. The coagulation tank is provided with four mutually isolated cavities, which are used to hold equal amounts of electroplating wastewater and corresponding heavy metal catching agents. The left and right side cavities are located between the outer frame and the coagulation tank. Two backflushing storage assemblies are installed in each of the left and right cavities. Each backflushing storage assembly is used to store a flocculant or coagulant aid. Four multi-pipe dosing assemblies are provided above the coagulation tank. The multi-pipe dosing assemblies are connected to the backflushing storage assemblies one by one. The multi-shaft coagulation and mixing assembly installed on the top frame of the steel structure is used to synchronously mix the liquid in the four cavities. The liquid drain pipe assembly and sewage drain pipe assembly are installed on the side walls of each cavity of the coagulation tank, and the control box is installed on the outer wall of one side of the outer casing. The output end of the control box is electrically connected to the input end of the multi-pipe dosing assembly and the multi-shaft coagulation mixing assembly.

[0005] Preferably, the backflushing storage assembly includes a storage tank fixedly installed in the cavity, a shut-off valve installed at the top port of the storage tank, and a drain pipe installed at the outlet end of the shut-off valve.

[0006] Preferably, a replenishing ball valve and a drain ball valve are respectively installed on the left and right outer walls of the storage tank, and a shut-off valve is installed at the bottom pipe opening of the storage tank.

[0007] Preferably, the multi-pipe dosing assembly includes a steel frame fixed at the top corner of the coagulation tank, a vertical pipeline centrifugal pump fixedly installed at the top of the steel frame, and a main switch valve installed at the outlet end of the vertical pipeline centrifugal pump. A right-angle pipe is installed at the outlet of the main switch valve, and a four-way branch pipe assembly parallel to the length direction of the coagulation tank is installed at the lower end of the right-angle pipe. Each outlet end of the four-way branch pipe assembly is equipped with an electromagnetic flow valve. The drain pipe is connected to the inlet of the vertical pipeline centrifugal pump through a flange.

[0008] Preferably, the four-way branch pipe assembly consists of a horizontal main pipe, two equal-diameter tees, and two end elbows. The horizontal main pipe is connected to a right-angle pipe. The electromagnetic flow valve is installed at the lower outlet position of the two equal-diameter tees and the two end elbows. A gap is provided between two adjacent horizontal main pipes in the X-axis direction.

[0009] Preferably, the drain pipe assembly and the sewage pipe assembly have the same structure, including a drain port provided on the side wall of the cavity, a switch valve sealed and installed in the drain port, and a pipe installed at the outlet end of the switch valve.

[0010] Preferably, the multi-shaft coagulation and stirring assembly includes four vertical shafts rotatably mounted on the top wall of the steel structure top frame via ball bearings, multiple Y-shaped stirring arms mounted radially at the lower ends of the vertical shafts at equal intervals, and three drive shafts horizontally rotating on the top wall of the steel structure top frame via vertical bearing seats. The drive shafts are located between two adjacent vertical shafts, with the vertical shafts passing through the gaps. Both ends of the drive shafts are fixed with bevel gear one, and a bevel gear two for meshing with bevel gear one is fixed at the upper position of the vertical shaft. A motor for driving one of the vertical shafts to rotate is installed on one side of the top of the steel structure top frame.

[0011] Preferably, the top wall of the steel structure top frame is fixed with a protective shell, and the bottom end of the protective shell is provided with a shaft hole for the vertical shaft to pass through.

[0012] Preferably, an electric heating component is installed at the lower part of the cavity of the coagulation box, and the output end of the electric heating component is electrically connected to the input end of the control box.

[0013] This invention also provides a method for the enrichment and detection of heavy metal ions in wastewater, using the aforementioned apparatus, comprising the following steps: S101: Take the electroplating wastewater to be tested and distribute it equally into the four cavities of the coagulation tank. The volume of wastewater in each cavity is the same. Add four different heavy metal chelating agents into the four cavities respectively, that is, each cavity corresponds to one heavy metal chelating agent, including sodium fumarate, small molecule piperazine chelating agent, light red polymer chelating agent and yellowish brown polymer chelating agent. Start the multi-shaft coagulation stirring assembly through the control box and set a high stirring speed to make the heavy metal chelating agent fully contact with the heavy metal ions in the wastewater and undergo a chelation reaction. Stirring continues for a predetermined time. S102: After stirring, the multi-pipe dosing assembly is started through the control box. One of the multi-pipe dosing assemblies simultaneously draws an equal amount of polyaluminum chloride solution from the backflushing storage assembly and injects it into the four cavities of the coagulation tank at the same time. During the injection process, all cavities receive the same dose and concentration of polyaluminum chloride solution, and the injection time is completely consistent. The multi-shaft coagulation stirring assembly continues to stir at a moderate speed so that the polyaluminum chloride can play a coagulation role and promote the formation of tiny colloidal suspensions from the chelated precipitates. S103: When obvious colloidal suspended matter appears in each cavity, another multi-pipe dosing assembly is turned on again through the control box. The multi-pipe dosing assembly draws an equal amount of 1 / 1000 concentration polyacrylamide solution from another corresponding backflushing storage assembly and injects it into the four cavities simultaneously. After the injection is completed, the operator adjusts the speed of the multi-shaft coagulation agitator to a low-speed agitation state of 50 revolutions per minute through the control box. After the low-speed agitation continues for the set time, the agitation is stopped, allowing the flocs in each cavity of the coagulation tank to settle. S104: The supernatant in each cavity of the coagulation tank is clearly separated from the bottom flocculated sludge layer. Open the drain pipe group, extract the supernatant sample and collect it in a clean sample bottle. Then open the sewage pipe group to discharge the flocculated sludge at the bottom of each cavity and perform subsequent treatment. Transfer the supernatant sample to the electrolytic cell of the electrochemical workstation. According to the requirements of the anodic stripping voltammetry, the staff adds an appropriate amount of supporting electrolyte to the supernatant sample and adjusts the pH value of the sample to a suitable range. Insert the working electrode, reference electrode and counter electrode into the electrolytic cell and connect the electrochemical workstation. The enrichment and removal effect of each heavy metal precipitator on heavy metal ions in electroplating wastewater is judged based on the detected residual concentration.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: The integrated device and method for enrichment and detection of heavy metal ions in wastewater is constructed with a structure that integrates an outer shell frame, a backwash storage unit, a coagulation tank, a multi-pipe dosing assembly, a steel top frame, and a multi-shaft coagulation and stirring assembly. The multi-pipe dosing assembly and the backwash storage unit work together. After different heavy metal precipitators are added to the corresponding cavities of the coagulation tank and mixed by the multi-shaft coagulation and stirring assembly, the multi-pipe dosing assembly is activated via a control box. The dosing unit simultaneously injects the flocculant or coagulant aid from the corresponding backflushing storage unit into each cavity of the coagulation tank in equal amounts. After the multi-shaft coagulation stirring unit stirs at low speed and enriches the flocs, the supernatant of each group of water samples is collected after sedimentation. The trace heavy metal ions in the supernatant of the electroplating wastewater after flocculation and sedimentation are detected by an electrochemical workstation and anodic stripping voltammetry. This allows the residual concentration data obtained by the electrochemical workstation in conjunction with anodic stripping voltammetry to truly and stably reflect the treatment effect of different heavy metal precipitants. The multi-tube dosing assembly and the backflushing reservoir assembly work together, and are automatically controlled by the control box, to simultaneously and equally inject flocculant or coagulant aid into each cavity of the coagulation tank. This solves the problem of asynchronous timing caused by manual sequential dosing. When all cavities of the coagulation tank receive the same dose of agent at the same instant, the entire process of floc formation, growth, and maturation in each cavity is strictly synchronized. After subsequent low-speed stirring and settling for the same duration, the settling degree of suspended particles and the compactness of floc structure in each group of supernatant are in the same physical state. Furthermore, the backflushing reservoir assembly pre-stores a fixed concentration of agent, and the multi-tube dosing assembly simultaneously distributes a quantitative amount of agent to each cavity, eliminating factors such as pipette reading errors, pipette tip residue, and operator technique fluctuations. There is no possibility of agent exchange between cavities, ensuring that each group of supernatant is only affected by its corresponding heavy precipitant. This ensures that the signal changes detected by subsequent anodic stripping voltammetry are entirely due to differences in the performance of the heavy precipitant, rather than errors introduced by the dosing operation. Attached Figure Description

[0015] Figure 1 This is a side view of the structure of the present invention; Figure 2 yes Figure 1 Sectional view at point AA; Figure 3 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 1 ; Figure 4 yes Figure 1 A three-dimensional structural cross-sectional view of point AA; Figure 5 This is a schematic diagram of the three-dimensional cross-sectional structure of the steel structure top frame and the outer shell frame after the multi-shaft concrete mixing assembly of the present invention has been removed. Figure 1 ; Figure 6 This is a three-dimensional structural diagram of the backflushing reservoir assembly and the multi-tube dosing assembly of the present invention; Figure 7 This is a schematic diagram of the three-dimensional cross-sectional structure of the steel structure top frame and the outer shell frame after the multi-shaft concrete mixing assembly of the present invention has been removed. Figure 2 ; Figure 8 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 2 ; Figure 9 This is a three-dimensional structural diagram of the steel structure top frame, multi-shaft concrete mixing assembly, and outer shell frame of the present invention in a separated state. Figure 10 This is a three-dimensional structural diagram of the multi-shaft coagulation and stirring assembly of the present invention.

[0016] In the diagram: 1. Outer frame; 101. Cavity; 2. Steel top frame; 3. Multi-shaft coagulation and mixing assembly; 301. Protective shell; 302. Motor; 303. Vertical shaft; 304. Y-shaped mixing arm; 305. Drive shaft; 306. Bevel gear one; 307. Bevel gear two; 4. Coagulation tank; 401. Cavity; 5. Backflushing storage assembly; 501. Storage tank; 502. Make-up ball valve; 503 504. Gate valve 1; 505. Drain pipe; 506. Gate valve 2; 507. Sewage ball valve; 6. Multi-pipe dosing assembly; 608. Steel frame; 609. Vertical pipeline centrifugal pump; 6000. Main switch valve; 6001. Right angle pipe; 602. Four-way branch pipe assembly; 603. Solenoid flow valve; 7. Drain pipe assembly; 8. Sewage pipe assembly; 9. Control box; 10. Electric heating assembly; 11. Gap section. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0018] Example 1, by Figures 1 to 4 The present invention includes an outer shell frame 1, a steel structure top frame 2 fixed to the top of the outer shell frame 1, and a coagulation tank 4 installed inside the outer shell frame 1. The coagulation tank 4 is provided with four mutually isolated cavities 401, which are used to hold equal amounts of electroplating wastewater and corresponding heavy precipitating agents. The left and right side cavities 101 are located between the outer frame 1 and the coagulation tank 4. Two backflushing storage components 5 are installed in each of the left and right cavities 101. Each backflushing storage component 5 is used to store a flocculant or coagulant aid. Four multi-pipe dosing components 6 are provided above the coagulation tank 4. The multi-pipe dosing components 6 are connected to the backflushing storage components 5 one by one. The multi-shaft coagulation agitator 3 is installed on the top frame of the steel structure 2. The multi-shaft coagulation agitator 3 is used to synchronously agitate the liquid in the four cavities 401. The drain pipe assembly 7 and the sewage pipe assembly 8 are installed on the side walls of each cavity 401 of the coagulation tank 4, and the control box 9 is installed on the outer wall of one side of the outer casing 1. The output end of the control box 9 is electrically connected to the input end of the multi-pipe dosing assembly 6 and the multi-shaft coagulation mixing assembly 3. An electric heating component 10 is installed at the lower position of the cavity 401 of the coagulation box 4. The output end of the electric heating component 10 is electrically connected to the input end of the control box 9. By configuring the electric heating component 10 in the coagulation box 4, the working temperature of the device can be further controlled by the electric heating component 10. When using an externally configured electrochemical workstation to detect the metal ion content in the supernatant, the operator sets the enrichment potential, enrichment time, settling time, and dissolution scan potential range in the control software, starts the detection program, and the working electrode reduces and enriches the trace heavy metal ions in the supernatant on the electrode surface under stirring conditions. Then, stirring is stopped and a positive potential scan is applied to record the dissolution current peak. The concentration of residual heavy metals in the supernatant is calculated by comparing the peak current with the standard curve or by the standard addition method. The above detection is performed sequentially on the supernatant of the four cavities corresponding to different heavy metal catching agents to obtain four sets of residual concentration data. Since the device has a total of four backflushing storage components 5, two of which pre-store flocculants and coagulants, and the remaining two backflushing storage components 5 can be prepared for operation in one and store pH adjusters in the other.

[0019] This embodiment provides a method for the enrichment and detection of heavy metal ions in wastewater, using the aforementioned apparatus, and includes the following steps: S101: Take the electroplating wastewater to be tested and distribute it in equal amounts into the four cavities 401 of the coagulation tank 4. The volume of wastewater in each cavity 401 is the same. Add four different heavy metal chelating agents into the four cavities 401 respectively, that is, each cavity 401 corresponds to one heavy metal chelating agent, including sodium fumarate, small molecule piperazine chelating agent, light red polymer chelating agent and yellowish brown polymer chelating agent. Start the multi-shaft coagulation stirring assembly 3 through the control box 9 and set a high stirring speed so that the heavy metal chelating agent can fully contact the heavy metal ions in the wastewater and undergo a chelation reaction. Stirring continues for a predetermined time. S102: After stirring, the multi-pipe dosing assembly 6 is started through the control box 9. One of the multi-pipe dosing assemblies 6 simultaneously draws an equal amount of polyaluminum chloride solution from the backflushing storage assembly 5 and injects it into the four cavities 401 of the coagulation tank 4. During the injection process, all cavities 401 receive the same dose and concentration of polyaluminum chloride solution, and the injection time is completely consistent. The multi-shaft coagulation stirring assembly 3 continues to stir at a moderate speed so that the polyaluminum chloride can play a coagulation role and promote the formation of tiny colloidal suspensions from the chelated precipitates. S103: When obvious colloidal suspended matter appears in each cavity 401, another multi-pipe dosing assembly 6 is turned on again through the control box 9. The multi-pipe dosing assembly 6 draws an equal amount of 1 / 1000 concentration polyacrylamide solution from another corresponding backflushing storage assembly 5 and injects it into the four cavities 401 simultaneously. After the injection is completed, the operator adjusts the speed of the multi-shaft coagulation stirring assembly 3 to a low-speed stirring state of 50 revolutions per minute through the control box 9. After the low-speed stirring continues for a set time, the stirring is stopped, allowing the flocs in each cavity 401 in the coagulation tank 4 to settle. S104: The supernatant in each cavity 401 of the coagulation tank 4 is clearly separated from the bottom flocculated sludge layer. Open the drain pipe group 7, extract the supernatant sample and collect it in a clean sample bottle. Then open the sewage drain pipe group 8 to discharge the flocculated sludge at the bottom of each cavity 401 and perform subsequent treatment. Transfer the supernatant sample to the electrolytic cell of the electrochemical workstation. According to the requirements of the anodic stripping voltammetry, the staff adds an appropriate amount of supporting electrolyte to the supernatant sample and adjusts the pH value of the sample to a suitable range. Insert the working electrode, reference electrode and counter electrode into the electrolytic cell and connect the electrochemical workstation. The enrichment and removal effect of each heavy metal precipitator on heavy metal ions in electroplating wastewater is judged according to the detected residual concentration.

[0020] Example 2, based on Example 1, is... Figure 5 , Figure 6 and Figure 7 As shown, the backflushing storage assembly 5 includes a storage tank 501 fixedly installed in the cavity 101, a shut-off valve 503 installed at the top port of the storage tank 501, and a drain pipe 504 installed at the outlet of the shut-off valve 503. The storage tank 501 contains the required treatment agent. When the shut-off valve 503 is normally open, the multi-pipe dosing assembly 6 takes the treatment agent from the storage tank 501 through the drain pipe 504. A replenishment ball valve 502 and a drain ball valve 506 are respectively installed on the left and right outer walls of the storage tank 501. A shut-off valve 505 is installed at the bottom pipe opening of the storage tank 501. The replenishment ball valve 502 is used to replenish the treatment agent. After the experiment or during regular maintenance, the staff connects the shut-off valve 505 to the external clean water supply, closes the shut-off valve 503 and the replenishment ball valve 502, and opens the drain ball valve 506 to flush away the residue on the inner wall of the storage tank 501. The multi-pipe dosing assembly 6 includes a steel frame 601 fixed at the top corner of the coagulation tank 4, a vertical pipeline centrifugal pump 602 fixedly installed at the top of the steel frame 601, and a main switch valve 603 installed at the outlet end of the vertical pipeline centrifugal pump 602. A right-angle pipe 604 is installed at the outlet of the main switch valve 603, and a four-way branch pipe assembly 605 parallel to the length direction of the coagulation tank 4 is installed at the lower end of the right-angle pipe 604. Each outlet end of the four-way branch pipe assembly 605 is equipped with an electromagnetic flow valve 606. The drain pipe 504 is connected to the inlet of the vertical pipeline centrifugal pump 602 through a flange. The four-way branch pipe assembly 605 consists of a horizontal main pipe, two equal-diameter tees and two end elbows. The horizontal main pipe is connected to the right-angle pipe 604. The electromagnetic flow valve 606 is installed at the lower outlet position of the two equal-diameter tees and the two end elbows. A gap 11 is provided between two adjacent horizontal main pipes in the X-axis direction. When the backflushing storage unit 5 and the multi-pipe dosing unit 6 inject the treatment agent into each cavity 401 of the coagulation tank 4, the vertical pipeline centrifugal pump 602 is turned on by the control box 9 and the main switch valve 603 is opened. Then, the vertical pipeline centrifugal pump 602 sends the treatment agent in the storage tank 501 into the four-way branch pipe assembly 605 through the main switch valve 603 and the right-angle pipe 604. The electromagnetic flow valve 606 at the outlet end of the four-way branch pipe assembly 605 injects the quantitative agent into each cavity 401 simultaneously. The dosage is controlled by the opening time of the electromagnetic flow valve 606 set by the control box 9. The drain pipe assembly 7 and the sludge drain pipe assembly 8 have the same structure, including a drain port set on the side wall of cavity 401, a switch valve sealed in the drain port, and a pipe installed at the outlet end of the switch valve. The drain pipe assembly 7 is used to extract supernatant samples from the corresponding cavity 401, while the sludge drain pipe assembly 8 is used to discharge the flocculated sludge at the bottom of each cavity 401, which facilitates cleaning of the coagulation box 4 and prevents cross-contamination between different batches of experiments.

[0021] Example 3, based on Example 2, by Figure 8 , Figure 9 and Figure 10 The multi-shaft coagulation mixing assembly 3 includes four vertical shafts 303 rotatably mounted on the top wall of the steel structure top frame 2 via ball bearings, multiple Y-shaped mixing arms 304 circumferentially radially mounted on the lower end of the vertical shafts 303, and three drive shafts 305 horizontally rotatable on the top wall of the steel structure top frame 2 via vertical bearing seats. The drive shafts 305 are located between two adjacent vertical shafts 303, and the vertical shafts 303 pass through the gap 11. Both ends of the drive shafts 305 are fixed with bevel gears 306. A bevel gear 307 for meshing with bevel gears 306 is fixed at the upper position of the vertical shaft 303. A motor 302 for driving one of the vertical shafts 303 to rotate is installed on one side of the top of the steel structure top frame 2. When the multi-shaft coagulation and mixing assembly 3 is working, the output shaft of the motor 302 drives one of the vertical shafts 303 to rotate. The vertical shaft 303 uses the Y-shaped stirring arm 304 located at its lower position to mix the wastewater and treatment agent in the cavity 401. The vertical shaft 303 and the transmission shaft 305 transmit power through bevel gear 1 306 and bevel gear 2 307, so that the four vertical shafts 303 rotate at the same speed. The control box 9 adjusts the frequency of the motor 302 to achieve two modes: high-speed mixing and low-speed flocculation, ensuring that the hydrodynamic conditions of each reaction system are consistent.

[0022] A protective shell 301 is fixed to the top wall of the steel structure top frame 2. The bottom end of the protective shell 301 is provided with a shaft hole for the vertical shaft 303 to pass through. The protective shell 301 is used to shield and protect each transmission shaft 305, bevel gear 1 306 and bevel gear 2 307. A gap 11 is left between two adjacent four-way branch pipe assemblies 605 directly below the protective shell 301. The gap 11 allows the four vertical shafts 303 to pass downward.

[0023] It should be noted that, in this document, relational 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 such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0024] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An integrated device for the enrichment and detection of heavy metal ions in wastewater, comprising an outer shell frame (1), a steel structure top frame (2) fixed to the top of the outer shell frame (1), and a coagulation tank (4) installed inside the outer shell frame (1), wherein the coagulation tank (4) is provided with four mutually isolated cavities (401), the cavities (401) being used to hold equal amounts of electroplating wastewater and corresponding heavy metal ion precipitating agents, characterized in that... ； The left and right side cavities (101) are located between the outer frame (1) and the coagulation tank (4). Two backflushing storage components (5) are installed in each of the left and right cavities (101). Each backflushing storage component (5) is used to store a flocculant or coagulant aid. Four multi-pipe dosing components (6) are provided above the coagulation tank (4). The multi-pipe dosing components (6) are connected to the backflushing storage components (5) one by one. The multi-shaft coagulation mixing assembly (3) is installed on the top frame (2) of the steel structure. The multi-shaft coagulation mixing assembly (3) is used to synchronously mix the liquid in the four cavities (401). The drain pipe assembly (7) and the sewage pipe assembly (8) are installed on the side wall of each cavity (401) of the coagulation box (4), and the control box (9) is installed on the outer wall of one side of the outer shell frame (1). The output end of the control box (9) is electrically connected to the input end of the multi-pipe dosing assembly (6) and the multi-shaft coagulation stirring assembly (3). The backflushing storage assembly (5) includes a storage tank (501) fixedly installed in the cavity (101), a shut-off valve (503) installed at the top port of the storage tank (501), and a drain pipe (504) installed at the outlet of the shut-off valve (503). The multi-pipe dosing assembly (6) includes a steel frame (601) fixed at the top corner of the coagulation tank (4), a vertical pipeline centrifugal pump (602) fixedly installed at the top of the steel frame (601), and a main switch valve (603) installed at the outlet of the vertical pipeline centrifugal pump (602). A right-angle pipe (604) is installed at the outlet of the main switch valve (603), and a four-way branch pipe assembly (605) parallel to the length direction of the coagulation tank (4) is installed at the lower end of the right-angle pipe (604). Each outlet of the four-way branch pipe assembly (605) is equipped with an electromagnetic flow valve (606). The drain pipe (504) is connected to the inlet of the vertical pipeline centrifugal pump (602) through a flange. The multi-shaft coagulation mixing assembly (3) includes four vertical shafts (303) rotatably mounted on the top wall of the steel structure top frame (2) via ball bearings, multiple Y-shaped mixing arms (304) rotatably mounted on the lower end of the vertical shafts (303) in a circumferentially equidistant radial structure, and three drive shafts (305) rotatably mounted on the top wall of the steel structure top frame (2) via vertical bearing seats. The drive shafts (305) are located between two adjacent vertical shafts (303), and the vertical shafts (303) pass through the gap (11). Both ends of the drive shafts (305) are fixed with bevel gear one (306), and a bevel gear two (307) is fixed at the upper position of the vertical shaft (303) for meshing with bevel gear one (306). A motor (302) for driving one of the vertical shafts (303) to rotate is installed on one side of the top of the steel structure top frame (2).

2. The integrated device for enrichment and detection of heavy metal ions in wastewater according to claim 1, characterized in that: The left and right outer walls of the storage tank (501) are respectively equipped with a replenishment ball valve (502) and a drain ball valve (506), and a stop valve (505) is installed at the bottom pipe opening of the storage tank (501).

3. The integrated device for enrichment and detection of heavy metal ions in wastewater according to claim 1, characterized in that: The four-way branch pipe assembly (605) consists of a horizontal main pipe, two equal-diameter tees and two end elbows. The horizontal main pipe is connected to the right-angle pipe (604). The electromagnetic flow valve (606) is installed at the lower outlet position of the two equal-diameter tees and the two end elbows. A gap (11) is provided between two adjacent horizontal main pipes in the X-axis direction.

4. The integrated device for enrichment and detection of heavy metal ions in wastewater according to claim 1, characterized in that: The drain pipe assembly (7) and the sewage pipe assembly (8) have the same structure, including a drain port set on the side wall of the cavity (401), a switch valve sealed in the drain port, and a pipe installed at the outlet end of the switch valve.

5. The integrated device for enrichment and detection of heavy metal ions in wastewater according to claim 1, characterized in that: The top wall of the steel structure top frame (2) is fixed with a protective shell (301), and the bottom end of the protective shell (301) is provided with a shaft hole for the vertical shaft (303) to pass through.

6. The integrated device for enrichment and detection of heavy metal ions in wastewater according to claim 1, characterized in that: An electric heating assembly (10) is installed at the lower position of the cavity (401) of the coagulation box (4), and the output end of the electric heating assembly (10) is electrically connected to the input end of the control box (9).

7. A method for the enrichment and detection of heavy metal ions in wastewater, using the apparatus as described in any one of claims 1-6, characterized in that: Includes the following steps: S101: Take the electroplating wastewater to be tested and divide it into equal amounts into the four cavities (401) of the coagulation tank (4). The volume of wastewater in each cavity (401) is the same. Add four different heavy metal chelating agents into the four cavities (401), that is, each cavity (401) corresponds to one heavy metal chelating agent, including sodium fumarate, small molecule piperazine chelating agent, light red polymer chelating agent and yellow-brown polymer chelating agent. Start the multi-shaft coagulation stirring assembly (3) through the control box (9) and set a high stirring speed so that the heavy metal chelating agent can fully contact the heavy metal ions in the wastewater and undergo a chelation reaction. Stirring continues for a predetermined time. S102: After stirring, the multi-pipe dosing assembly (6) is turned on by the control box (9). One of the multi-pipe dosing assemblies (6) simultaneously draws an equal amount of polyaluminum chloride solution from the backflushing storage assembly (5) and injects it into the four cavities (401) of the coagulation tank (4). During the injection process, all cavities (401) obtain the same dose and concentration of polyaluminum chloride solution, and the injection time is completely consistent. The multi-shaft coagulation stirring assembly (3) continues to stir at a moderate speed so that polyaluminum chloride can play a coagulation role and promote the formation of tiny colloidal suspensions from the chelated precipitate. S103: When obvious colloidal suspended matter appears in each cavity (401), another multi-pipe dosing assembly (6) is opened again through the control box (9). The multi-pipe dosing assembly (6) extracts an equal amount of 1 / 1000 concentration polyacrylamide solution from another corresponding backflushing storage assembly (5) and injects it into the four cavities (401) simultaneously. After the injection is completed, the staff adjusts the speed of the multi-shaft coagulation stirring assembly (3) to a low-speed stirring state of fifty revolutions per minute through the control box (9). After the low-speed stirring continues for a set time, the stirring is stopped, allowing the flocs in each cavity (401) in the coagulation tank (4) to settle. S104: The supernatant in each cavity (401) of the coagulation box (4) is clearly separated from the bottom flocculated sludge layer. Open the drain pipe group (7), extract the supernatant sample and collect it in a clean sample bottle. Then open the sewage pipe group (8) to discharge the flocculated sludge at the bottom of each cavity (401) and perform subsequent treatment. Transfer the supernatant sample to the electrolytic cell of the electrochemical workstation. According to the requirements of the anodic stripping voltammetry, the staff adds an appropriate amount of supporting electrolyte to the supernatant sample, adjusts the pH value of the sample to a suitable range, inserts the working electrode, reference electrode and counter electrode into the electrolytic cell, connects the electrochemical workstation, and judges the enrichment and removal effect of each heavy metal precipitator on the electroplating wastewater based on the detected residual concentration.

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