Silver-containing wastewater treatment system

Abstract

The utility model discloses a silver-containing wastewater treatment system, which comprises a reaction tank used for carrying out reaction and sedimentation on silver-containing wastewater and a neutralizing agent to obtain suspension liquid and silver-containing precipitates; the filter is used for receiving and filtering the suspension from the reaction tank to generate slurry and first filtrate; the centrifugal filter is used for receiving and filtering the slurry from the filter to generate silver-containing filter residues and second filtrate; wherein a first recovery pipeline is arranged between the filter and the reaction tank and is used for selectively sending the first filtrate separated from the filter back to the reaction tank for reaction again, and a second recovery pipeline is arranged between the centrifugal filter and the reaction tank and is used for selectively sending the second filtrate separated from the centrifugal filter back to the reaction tank for reaction again. Therefore, silver ions in the first filtrate and the second filtrate can be recycled as much as possible, and the method is suitable for treating silver-containing wastewater with different silver ion concentrations.

Description

Technical Field

[0001] This utility model relates to the field of silver-containing wastewater treatment technology, and specifically to a silver-containing wastewater treatment system. Background Technology

[0002] Because silver-containing wastewater can easily pollute the environment, and silver, as a precious metal, has certain recycling value, it is necessary to minimize the concentration of silver ions in the wastewater and recover them during the production process. Currently, the main methods for treating silver in wastewater include electrolysis, exchange, adsorption, and precipitation.

[0003] Electrolysis is often used for waste fixing solutions and silver plating waste solutions, but it cannot be carried out under conditions of low metal ion concentration and is not suitable for silver-containing wastewater with low silver ion concentration.

[0004] Ion exchange has the advantage of recovering trace amounts of silver from waste liquid, but ion exchange resins are easily contaminated or oxidized and fail, require frequent regeneration, have high operating costs, and have high requirements for adsorbents, thus limiting their widespread use.

[0005] The adsorption method involves the adsorption and recovery of silver from silver-containing wastewater through the physicochemical effect of the active surface of the adsorbent. Its adsorption effect mainly depends on the performance of the adsorbent used, and it is not suitable for use when the wastewater volume is large or the silver content in the wastewater is high.

[0006] Precipitation involves adding sodium sulfide solution under specific pH conditions to form silver sulfide precipitate, thus removing silver ions. However, because silver sulfide precipitate particles are small and easily form colloids, natural gravity sedimentation is ineffective and can introduce sulfur pollutants into wastewater, necessitating further treatment of these pollutants.

[0007] It is evident that current recycling methods are not suitable for silver-containing wastewater with varying silver ion concentrations, and their recycling capacity is limited. Utility Model Content

[0008] One of the technical problems this invention aims to solve is: how to design a silver-containing wastewater treatment device suitable for different silver ion concentrations, and how to effectively recover silver ions.

[0009] To achieve the above objectives, this utility model provides a treatment system for silver-containing wastewater, comprising:

[0010] The reaction tank is used to react and settle silver-containing wastewater with a neutralizing agent to obtain a suspension and silver-containing precipitate.

[0011] A filter for receiving and filtering the suspension from the reaction tank to generate a slurry and a first filtrate;

[0012] A centrifugal filter for receiving and filtering slurry from the filter to produce silver-containing residue and a second filtrate;

[0013] A first recovery pipe is provided between the filter and the reaction tank for selectively returning the first filtrate separated from the filter to the reaction tank for further reaction. A second recovery pipe is provided between the centrifugal filter and the reaction tank for selectively returning the second filtrate separated from the centrifugal filter to the reaction tank for further reaction.

[0014] In some embodiments, the filter has a first outlet, and the processing system further includes a first filtrate storage tank, with a filtrate pipe connecting the first outlet to the inlet of the first filtrate storage tank.

[0015] In some embodiments, the outlet of the first filtrate storage tank is provided with a three-way valve, and the two outlets of the three-way valve are respectively connected to the first recovery pipeline and the clear liquid discharge pipeline.

[0016] In some embodiments, the filter has a second outlet, and a slurry pipe is connected between the second outlet and the centrifugal filter, with a second pump body installed on the slurry pipe.

[0017] In some embodiments, a slurry tank is provided on the slurry pipeline, the slurry tank being located between the second pump body and the second outlet.

[0018] In some embodiments, the reaction tank has a first inlet connected to a silver-containing wastewater inlet pipe, and a second recovery pipe connected to the silver-containing wastewater inlet pipe.

[0019] In some embodiments, the reaction tank has a second inlet connected to a neutralizing agent inlet pipe.

[0020] In some embodiments, a suspension pipe is connected between the outlet of the reaction tank and the inlet of the filter, and a first pump body is provided on the suspension pipe.

[0021] In some embodiments, the processing system further includes a control system that is communicatively connected to the reaction tank, the filter, and the centrifugal filter.

[0022] In some embodiments, the filter is a drum filter or a belt filter.

[0023] The above technical solution involves setting up a first recovery pipe between the filter and the reaction tank to selectively return the first filtrate separated from the filter to the reaction tank for further reaction, and setting up a second recovery pipe between the centrifugal filter and the reaction tank to selectively return the second filtrate separated from the centrifugal filter to the reaction tank for further reaction. This allows for the recovery of silver ions from the first and second filtrates as much as possible, and is suitable for the treatment of silver-containing wastewater with different silver ion concentrations. Attached Figure Description

[0024] Figure 1 This is a process flow diagram of the silver-containing wastewater treatment system disclosed in this utility model.

[0025] Explanation of reference numerals in the attached figures

[0026] 1. Reaction tank; 2. First pump body; 3. Filter; 4. Slurry tank; 5. Second pump body; 6. Centrifugal filter; 7. First filtrate storage tank; 8. Control system; 9. Neutralizing agent inlet pipe; 10. Silver-containing wastewater inlet pipe; 11. Suspension pipe; 12. Slurry pipe; 13. Filtrate pipe; 14. Clear liquid discharge pipe; 15. First recovery pipe; 16. Second recovery pipe. Detailed Implementation

[0027] The specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of this utility model.

[0028] To address the problem that existing silver-containing wastewater recovery methods are not applicable to silver-containing wastewater with varying silver ion concentrations, this invention provides a silver-containing wastewater treatment system, comprising:

[0029] Reaction tank 1 is used to react and settle silver-containing wastewater with a neutralizing agent to obtain a suspension and silver-containing precipitate.

[0030] Filter 3 is used to receive and filter the suspension from reaction tank 1 to generate slurry and first filtrate;

[0031] Centrifugal filter 6 is used to receive and filter the slurry from filter 3 to produce silver-containing filter residue and second filtrate;

[0032] A first recovery pipe 15 is provided between the filter 3 and the reaction tank 1 to selectively return the first filtrate separated from the filter 3 to the reaction tank 1 for further reaction. A second recovery pipe 16 is provided between the centrifugal filter 6 and the reaction tank 1 to selectively return the second filtrate separated from the centrifugal filter 6 to the reaction tank 1 for further reaction.

[0033] like Figure 1As shown, the reaction tank 1 may include a tank body for sedimentation and neutralization reaction, a stirring mechanism disposed in the middle of the tank body, and a level gauge; the filter 3 may include a cylinder body for filtering suspension, a filter medium disposed in the cylinder body, a level gauge, and a pressure transmitter; the centrifugal filter 6 may include a tank body for filtering slurry, a filter medium disposed in the tank body, and a level gauge.

[0034] The treatment system consists of a reaction tank 1, a filter 3, and a centrifugal filter 6 arranged sequentially from upstream to downstream. The silver-containing wastewater first undergoes neutralization and sedimentation in the reaction tank 1 to obtain a suspension and silver-containing precipitate. The suspension then undergoes a first filtration in the filter 3 to obtain a slurry and a first filtrate. Finally, the slurry undergoes a second filtration in the centrifugal filter 6 to obtain silver-containing filter residue and a second filtrate. The first filtrate from the filter 3, after passing inspection, can be discharged from the treatment system. The silver-containing filter residue from the centrifugal filter 6 is collected and transported to a filter residue recovery device connected to the centrifugal filter 6 to recover silver ions from the silver-containing wastewater.

[0035] For the first filtrate that fails the test of filter 3, a first recovery pipe 15 is set between filter 3 and reaction tank 1 to further recover the first filtrate; for the second filtrate of centrifugal filter 6, a second recovery pipe 16 is set between centrifugal filter 6 and reaction tank 1 to further recover the filtrate.

[0036] Through the above technical solution, a first recovery pipe 15 is set between the filter 3 and the reaction tank 1 to selectively send the first filtrate separated from the filter 3 back to the reaction tank 1 for further reaction. A second recovery pipe 16 is set between the centrifugal filter 6 and the reaction tank 1 to selectively send the second filtrate separated from the centrifugal filter 6 back to the reaction tank 1 for further reaction. In this way, silver ions in the first and second filtrates can be recovered as much as possible, which is suitable for the treatment of silver-containing wastewater with different silver ion concentrations.

[0037] The silver-containing wastewater treatment system of this invention continuously carries out reaction sedimentation, filtration and centrifugal filtration processes, which can keep the silver content in the clear liquid discharged from the treatment system stable below 50% of the discharge standard of 0.2 mg / L, making the treatment of silver-containing wastewater stable and controllable, and achieving stable discharge of wastewater that meets the standards.

[0038] In some embodiments, the filter 3 has a first outlet, and the processing system further includes a first filtrate storage tank 7, with a filtrate pipe 13 connecting the first outlet to the inlet of the first filtrate storage tank 7. For example... Figure 1 As shown, the first outlet can be set at the top of the filter 7. The first filtrate generated by the filter 3 automatically overflows from the first outlet through the filtrate pipe 13 to the first filtrate storage tank 7 to achieve the collection of the first filtrate.

[0039] In some embodiments, the outlet of the first filtrate storage tank 7 is provided with a three-way valve, and the two outlets of the three-way valve are respectively connected to the first recovery pipe 15 and the clear liquid discharge pipe 14.

[0040] A sampling port can be installed at the outlet of the first filtrate storage tank 7. Once the first filtrate storage tank 7 has collected a preset amount, a sample of the first filtrate in the first filtrate storage tank 7 can be taken for testing. For example... Figure 1 As shown, a three-way valve is also installed at the outlet of the first filtrate storage tank 7, which is connected to the first recovery pipe 15 and the clear liquid discharge pipe 14 respectively. When the first filtrate is qualified, the connection between the three-way valve and the clear liquid discharge pipe 14 is opened to discharge the first filtrate outside the treatment system; when the first filtrate is unqualified, the connection between the three-way valve and the first recovery pipe 15 is opened to discharge the first filtrate back into the reaction tank 1 for reaction sedimentation and filtration operations again.

[0041] In some embodiments, the filter 3 has a second outlet, and a slurry pipe 12 is connected between the second outlet and the centrifugal filter 6, with a second pump body 5 installed on the slurry pipe 12.

[0042] like Figure 1 As shown, the second outlet can be set at the bottom of the filter 3. The slurry generated by the filter 3 is discharged from the second outlet through the slurry pipe 12 to the centrifugal filter 6 for a second filtration. The slurry is transported between the filter 3 and the centrifugal filter 6 by the second pump body 5 set on the second slurry pipe 12.

[0043] In some embodiments, a slurry tank 4 is provided on the slurry pipe 12, and the slurry tank 4 is located between the second pump body 5 and the second outlet. For example... Figure 1 As shown, a slurry tank 4 is also provided on the slurry pipeline 12, which can serve as a slurry transfer device for pre-collecting the slurry from the filter 3 and performing automatic backwashing. When the collection volume of the slurry tank 4 reaches a preset value, the slurry in the slurry tank 4 is then transported to the centrifugal filter 6.

[0044] In some embodiments, the reaction tank 1 has a first inlet connected to a silver-containing wastewater inlet pipe 10, and a second recovery pipe 16 connected to the silver-containing wastewater inlet pipe 10.

[0045] like Figure 1 As shown, the first inlet can be located at the top of the reaction tank 1 and connected to the silver-containing wastewater inlet pipe 10. A second recovery pipe 16 is connected to the silver-containing wastewater inlet pipe 10 near the first inlet. That is, both the second filtrate and the silver-containing wastewater enter the reaction tank 1 through the first inlet for reaction and sedimentation. A feed control valve can be installed on the silver-containing wastewater inlet pipe 10 to control the feeding of the silver-containing wastewater.

[0046] In some embodiments, the reaction tank 1 has a second inlet connected to a neutralizing agent inlet pipe 9. For example... Figure 1 As shown, the second inlet can be located at the top of the reaction tank 1 and connected to the neutralizing agent inlet pipe 9. A feed control valve can be installed on the neutralizing agent inlet pipe 9 to control the feeding of the neutralizing agent.

[0047] In some embodiments, a suspension pipe 11 is connected between the outlet of the reaction tank 1 and the inlet of the filter 3, and a first pump body 2 is installed on the suspension pipe 11. Figure 1 As shown, the outlet can be located at the bottom of the reaction tank 1. The suspension generated in the reaction tank is transported from the outlet to the filter 3 via the suspension pipe 11 for the first filtration. The transport of the suspension between the reaction tank 1 and the filter 3 is achieved by the second pump body 5 installed on the second slurry pipe 12. In addition, the suspension pipe 11 is equipped with a discharge control valve near the outlet of the reaction tank 1 to control the discharge of the suspension, and a feed control valve near the inlet of the filter 3 to control the feed of the suspension.

[0048] In some embodiments, the processing system also includes a control system 8, which is communicatively connected to the reaction tank 1, the filter 3, and the centrifugal filter 6.

[0049] like Figure 1 As shown, the control system 8 can be a control cabinet with a pre-installed programmable control system, which is connected to the reaction tank 1, filter 3 and centrifuge 6 respectively, and realizes automatic control of the entire system according to the set parameters.

[0050] Specifically, it is communicatively connected to reaction tank 1, filter 3, centrifugal filter 6, slurry tank 4, first filtrate storage tank 7, and the pipelines, inlet and outlet valves, and pumps between them. Reaction tank 1 can feed and discharge materials according to the liquid level and reaction time. The first pump 2 can start and stop feeding materials to filter 3 according to the reaction time, the liquid level and pressure of filter 3. Filter 3 can automatically backwash or continuously feed materials according to its own pressure difference and set time. Slurry tank 4 can automatically feed and discharge materials according to the pressure at filter 3 and the internal liquid level, etc., and the system liquid level and pressure interlock is set.

[0051] In some embodiments, filter 3 is an expansion drum filter or a belt filter. Preferably, it is an expansion drum filter, which includes a filter housing, an expansion membrane, a membrane support, pipelines, a level gauge, a pressure transmitter, and inlet / outlet automatic control valves. It can handle various viscous and high-concentration particles, slurries, and filter media, and has a very wide range of applications.

[0052] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings; however, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, including combinations of various specific technical features in any suitable manner. To avoid unnecessary repetition, the present invention will not describe the various possible combinations separately. However, these simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A treatment system for silver-containing wastewater, characterized in that, include: The reaction tank (1) is used to react and settle silver-containing wastewater with a neutralizing agent to obtain a suspension and silver-containing precipitate; Filter (3) is used to receive and filter the suspension from the reaction tank (1) to generate a slurry and a first filtrate; Centrifugal filter (6) for receiving and filtering slurry from said filter (3) to generate silver-containing filter residue and second filtrate; A first recovery pipe (15) is provided between the filter (3) and the reaction tank (1) for selectively returning the first filtrate separated from the filter (3) to the reaction tank (1) for further reaction. A second recovery pipe (16) is provided between the centrifugal filter (6) and the reaction tank (1) for selectively returning the second filtrate separated from the centrifugal filter (6) to the reaction tank (1) for further reaction.

2. The silver-containing wastewater treatment system according to claim 1, characterized in that, The filter (3) has a first outlet, and the processing system further includes a first filtrate storage tank (7), with a filtrate pipe (13) connected between the first outlet and the inlet of the first filtrate storage tank (7).

3. The silver-containing wastewater treatment system according to claim 2, characterized in that, The outlet of the first filtrate storage tank (7) is equipped with a three-way valve, and the two outlets of the three-way valve are respectively connected to the first recovery pipe (15) and the clear liquid discharge pipe (14).

4. The silver-containing wastewater treatment system according to claim 2, characterized in that, The filter (3) has a second outlet, and a slurry pipe (12) is connected between the second outlet and the centrifugal filter (6). A second pump body (5) is provided on the slurry pipe (12).

5. The silver-containing wastewater treatment system according to claim 4, characterized in that, A slurry tank (4) is provided on the slurry pipe (12), and the slurry tank (4) is located between the second pump body (5) and the second outlet.

6. The silver-containing wastewater treatment system according to claim 1, characterized in that, The reaction tank (1) has a first inlet, which is connected to a silver-containing wastewater inlet pipe (10), and the second recovery pipe (16) is connected to the silver-containing wastewater inlet pipe (10).

7. The silver-containing wastewater treatment system according to claim 6, characterized in that, The reaction tank (1) has a second inlet, which is connected to a neutralizing agent inlet pipe (9).

8. The silver-containing wastewater treatment system according to claim 1, characterized in that, A suspension pipe (11) is connected between the outlet of the reaction tank (1) and the inlet of the filter (3), and a first pump body (2) is provided on the suspension pipe (11).

9. The silver-containing wastewater treatment system according to claim 1, characterized in that, The processing system also includes a control system (8), which is communicatively connected to the reaction tank (1), the filter (3), and the centrifugal filter (6).

10. The silver-containing wastewater treatment system according to claim 1, characterized in that, The filter (3) is an expansion drum filter or a belt filter.

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