A system and method for removing lead and cadmium ions from industrial waste liquid

Abstract

The present invention relates to a system and method for removing lead and cadmium ions from industrial waste liquid. The system and method include a resin tank filled with resin, a first waste liquid injection pipe connecting the top of the resin tank to a raw water tank, and a regeneration pipe connecting the bottom of the resin tank to an acid tank, an alkali tank and a water tank respectively. When removing lead and cadmium ions, the industrial waste liquid to be treated in the raw water tank is injected from the top of the resin tank. During the process of flowing through the resin, the lead and cadmium ions are exchanged with the sodium ions of the functional groups of the resin, and the lead and cadmium ions are removed. When the resin is saturated and regenerated, the regeneration liquid in the acid tank is first injected from the bottom of the resin tank to regenerate the resin. Then, the transformation liquid in the alkali tank is injected from the bottom of the resin tank to transform the resin. Then, the cleaning liquid in the water tank is injected from the bottom of the resin tank to rinse the resin. Finally, the emptying valve is opened, and the residual liquid of the cleaning liquid used to rinse the resin can be emptied to remove the lead and cadmium ions again. The present invention has the advantages of continuous and stable production, space saving, and reduced production costs.

Description

Technical Field

[0001] The invention relates to the technical field of industrial waste liquid treatment, and in particular to a system and method for removing lead and cadmium ions from industrial waste liquid. Background Art

[0002] Some industrial waste liquids contain a large amount of lead and cadmium ions, such as the industrial waste liquid from battery manufacturing. Lead and cadmium are heavy metal elements and harmful substances. If they are discharged directly, they will cause pollution to the soil and water bodies after a large amount of accumulation, affecting plant growth and the health of aquatic organisms; lead and cadmium are also harmful to human health. Long-term contact or ingestion of liquids containing lead and cadmium can cause damage to the central nervous system, kidney damage, blood diseases, etc., especially for children and pregnant women. The intake of lead and cadmium will have a long-term impact on physical development and health. In order to protect the environment and human health, lead and cadmium must be removed during the treatment of industrial waste liquids to reduce their harm to the ecological environment and human health.

[0003] At present, the methods for removing lead and cadmium ions mainly include one-step purification method, new mesoporous material method, biological adsorption method, membrane separation technology, chemical precipitation method, etc.

[0004] One-step purification is a sewage treatment method that integrates multiple treatment steps such as neutralization, flocculation, sedimentation, and filtration. It usually includes functional units such as neutralization, flocculation, sedimentation, and filtration. Through the organic combination of these functional units, multiple treatment steps are combined into one, thereby achieving efficient removal of harmful substances in sewage. However, when treating lead and cadmium wastewater, the one-step purification method also has some problems. First, due to the pH fluctuation of lead and cadmium wastewater, there will be a phenomenon of pH control lag in continuous operation, and it is not easy to control the appropriate pH value in the sedimentation section, which makes the precipitation effect of lead and cadmium unsatisfactory; second, if the wastewater after neutralization and sedimentation directly enters the coagulation and sedimentation process without effective filtration and other processes, the change in pH value will cause the precipitation to be resolved; third, the concentration of lead and cadmium in the wastewater will also change during the treatment process, which will make it difficult to control the dosage of the flocculation and sedimentation treatment process, resulting in unstable concentrations of lead and cadmium in the drainage; at the same time, a large amount of sediment will be generated, which requires subsequent treatment.

[0005] The new mesoporous material method uses the highly structured and large specific surface area characteristics of some new mesoporous materials to effectively adsorb and remove lead and cadmium ions from wastewater. These materials usually have excellent adsorption properties and high selectivity to achieve efficient removal effects, but their preparation costs are relatively high.

[0006] Biosorption is a method of using certain microorganisms, algae or biological materials to adsorb and remove lead and cadmium ions. This method is environmentally friendly and economical, but it requires appropriate culture conditions and control parameters, has strict requirements on culture conditions and control parameters, is relatively complex to operate, and is also affected by factors such as temperature and pH value.

[0007] Membrane separation technology, including reverse osmosis, ion exchange membrane, etc., separates lead and cadmium ions from other solutes in wastewater through the selectivity and permeability of the membrane to achieve the removal effect. This method has the advantages of high efficiency, energy saving, and continuous operation, but the cost of the membrane is high, the operation and maintenance requirements are relatively complex, and the pretreatment requirements for the wastewater are high.

[0008] Chemical precipitation method, by adding appropriate chemical reagents, makes the lead and cadmium ions in the waste liquid react with the reagents to form insoluble precipitates, and then precipitates and separates. Commonly used chemical reagents include sulfides, carbonates, etc., but they will produce a large amount of waste residue, which will affect subsequent treatment, and the waste liquid and waste residue need to be treated. Summary of the invention

[0009] To this end, the present invention provides a system for removing lead and cadmium ions from industrial waste liquid, which mainly solves the above-mentioned technical problems existing in the prior art when removing lead and cadmium ions from industrial waste liquid.

[0010] In order to achieve the above object, the present invention provides the following technical solutions:

[0011] A system for removing lead and cadmium ions from industrial waste liquid comprises a raw water tank; the raw water tank is used to contain the industrial waste liquid to be treated; the raw water tank is provided with a raw water pump; and further comprises:

[0012] At least one resin tank; the resin tank is filled with resin; the resin is an ion exchange resin used to adsorb lead and cadmium ions in the industrial waste liquid; the top and bottom of the resin tank are respectively provided with a resin tank injection pipe and a resin tank outlet pipe connected to the inside thereof; the bottom of the resin tank is provided with a drain valve for draining the resin;

[0013] An acid liquid tank, used for containing regeneration liquid; the acid liquid tank is provided with a regeneration pump;

[0014] An alkali liquid tank, used for containing the transformation liquid; the alkali liquid tank is provided with a transformation pump;

[0015] A water tank, used to contain cleaning liquid; the water tank is provided with a flushing pump;

[0016] A liquid outlet pipe, used for discharging the liquid from which lead and cadmium ions are removed;

[0017] Acid liquid discharge pipe; the acid liquid discharge pipe is provided with an acid liquid discharge solenoid valve;

[0018] Alkali liquid discharge pipe; the alkali liquid discharge pipe is provided with an alkali liquid discharge solenoid valve;

[0019] A water discharge pipe; the water discharge pipe is provided with a water discharge solenoid valve;

[0020] Regeneration tube;

[0021] The raw water pump is connected to the resin tank injection pipe through a first waste liquid injection pipe; the first waste liquid injection pipe is provided with a first waste liquid input solenoid valve; the liquid outlet pipe is connected to the resin tank liquid outlet pipe; the resin tank liquid outlet pipe between the liquid outlet pipe and the resin tank is provided with a resin tank liquid outlet solenoid valve;

[0022] The regeneration pump is connected to the regeneration pipe through an acid injection pipe, the transformation pump is connected to the alkali injection pipe through an alkali injection pipe, and the flushing pump is connected to the water injection pipe; the acid injection pipe is provided with an acid injection solenoid valve; the alkali injection pipe is provided with an alkali injection solenoid valve; the water injection pipe is provided with a water injection valve;

[0023] The regeneration pipe is connected to the resin tank liquid outlet pipe between the resin tank liquid outlet solenoid valve and the resin tank through the regeneration liquid inlet pipe; the regeneration liquid inlet pipe is provided with a regeneration liquid inlet solenoid valve;

[0024] The resin tank injection pipe is connected to the acid discharge pipe, the alkali discharge pipe and the water discharge pipe respectively through the regeneration liquid discharge pipe; the regeneration liquid discharge pipe is provided with a regeneration liquid outlet electromagnetic valve.

[0025] Optionally, it also includes a safety filter; the first waste liquid injection pipe is connected to the safety filter; the safety filter is connected to the resin tank injection pipe through a second waste liquid injection pipe; the second waste liquid injection pipe is provided with a second waste liquid input solenoid valve.

[0026] Optionally, the regeneration pipe is connected to the first waste liquid injection pipe between the first waste liquid input solenoid valve and the safety filter through a cleaning pipe; the cleaning pipe is provided with a cleaning valve.

[0027] Preferably, the safety filter is provided with a second pressure gauge.

[0028] Preferably, the first waste liquid injection pipe is provided with a first pressure gauge; the acid liquid injection pipe is provided with a third pressure gauge; the alkali liquid injection pipe is provided with a fourth pressure gauge; and the water injection pipe is provided with a fifth pressure gauge.

[0029] Preferably, the liquid outlet pipe is provided with a liquid outlet solenoid valve.

[0030] Preferably, the regeneration liquid is a 5% hydrochloric acid or sulfuric acid solution; the transformation liquid is a 5% sodium hydroxide solution; and the cleaning liquid is pure water or tap water.

[0031] Optionally, the resin tank liquid outlet pipe of the preceding resin tank and the resin tank liquid injection pipe of the succeeding resin tank of the adjacent resin tanks among the plurality of resin tanks are connected via a resin tank connecting pipe; the resin tank connecting pipe is provided with a third waste liquid input solenoid valve.

[0032] Furthermore, the present invention also provides a method for removing lead and cadmium ions from industrial waste liquid, which specifically comprises the following steps:

[0033] S01: Turn on the raw water pump; inject the industrial wastewater containing lead and cadmium ions in the raw water tank into the resin tank;

[0034] S02: The lead and cadmium ions in the industrial wastewater undergo ion exchange with the functional groups on the surface of the resin balls in the resin tank, and the lead and cadmium ions are adsorbed by the resin ball particles; the raw water from which the lead and cadmium ions are removed is adjusted in pH value and then discharged into a qualified water pool for reuse;

[0035] S03: After the resin is saturated with adsorption, turn off the raw water pump; turn on the regeneration pump to acid-wash and regenerate the resin;

[0036] S04: Use the regeneration liquid at a preset flow rate and perform pickling for a preset time;

[0037] S05: Turn off the regeneration pump, turn on the flushing pump, and use the cleaning fluid at a preset flow rate for a preset time to flush;

[0038] S06: Turn off the flushing pump, turn on the transformation pump, and transform the resin;

[0039] S07: using the transformation fluid at a preset flow rate to perform transformation for a preset time;

[0040] S08: Turn off the transformation pump, turn on the flushing pump, and use the cleaning fluid at a preset flow rate for a preset time to flush;

[0041] S09: Turn off the flushing pump, open the drain valve, and drain the resin; after the resin is drained, proceed to the next lead and cadmium ion removal operation.

[0042] Preferably, the regeneration liquid in step S04 is a 5% hydrochloric acid or sulfuric acid solution, and the resin is acid-washed at a flow rate of 4BV / H for 30 minutes; the transformation liquid in step S07 is a 5% sodium hydroxide solution, and the resin is alkaline-washed at a flow rate of 48BV / H for 30 minutes; the cleaning liquids in step S05 and step S08 are both pure water or tap water, and the resin is flushed at a flow rate of 10BV / H for 30 minutes.

[0043] The present invention has at least the following beneficial effects:

[0044] It is provided with a resin tank filled with resin, which is an ion exchange resin used to adsorb lead and cadmium ions in industrial waste liquid. The resin tank injection pipe on the top of the resin tank is connected with the raw water tank through a first waste liquid injection pipe, and the resin tank outlet pipe at the bottom of the resin tank is connected with the acid tank, alkali tank and water tank respectively through a regeneration pipe. The acid tank contains regeneration liquid, the alkali tank contains transformation liquid, and the water tank contains cleaning liquid. During the lead and cadmium ion removal operation, the untreated industrial waste liquid in the raw water tank is transported to the resin tank, and the industrial waste liquid flows in from the top of the resin tank. During the flow through the resin, the lead and cadmium ions in the industrial waste liquid are exchanged with the sodium ions of the resin functional groups, and a large amount of lead and cadmium ions are removed. When the resin is saturated, the resin is regenerated. First, the regeneration liquid in the acid tank is injected from the bottom of the resin tank to regenerate the resin; then, the transformation liquid in the alkali tank is injected from the bottom of the resin tank to transform the resin; finally, the cleaning liquid in the water tank is injected from the bottom of the resin tank to rinse the resin; then, the drain valve is opened to drain the residual cleaning liquid used to rinse the resin. After regeneration is completed, the lead and cadmium ions are removed again.

[0045] It can be seen that the system and method for removing lead and cadmium ions from industrial waste liquid of the present invention have at least the following advantages:

[0046] 1. Industrial waste liquid flows in from the top of the resin tank and falls naturally under its own weight. During the process of flowing through the resin, the lead and cadmium ions in the waste liquid are exchanged with the sodium ions of the resin functional groups, and the lead and cadmium ions are removed in large quantities. The lead and cadmium ion concentrations of the effluent meet the discharge requirements.

[0047] 2. By setting up a raw water tank, a resin tank, an acid tank, an alkali tank, a water tank and pipes connecting them, and setting corresponding solenoid valves on the pipes, the pipeline layout of this application is simple, space is saved, and construction costs are reduced.

[0048] 3. In the regeneration process, the corresponding liquids are injected from the bottom of the resin tank and flow out from the top, which can fully regenerate the resin for acid washing, alkaline washing and flushing without leaving dead corners, improve removal efficiency, extend the service life of the resin and reduce production costs.

[0049] 4. Ion exchange resin is used to remove lead and cadmium ions, and the resin is regenerated when it is saturated. It can achieve continuous and stable production, effectively avoid the generation of sludge, and solve the problem of unstable effluent. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly explain the prior art and the present invention, the following briefly introduces the drawings required for describing the prior art and the embodiments of the present invention. Obviously, the drawings described below are only exemplary, and for those of ordinary skill in the art, other drawings can be derived from the provided drawings without creative work.

[0051] The structures, proportions, sizes, etc. illustrated in this specification are only used to match the contents disclosed in the specification so that people familiar with this technology can understand and read them. They are not used to limit the conditions under which the present invention can be implemented. Any structural modification, change in proportion or adjustment of size should still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0052] Figure 1 A schematic diagram of the composition structure of a system for removing lead and cadmium ions from industrial waste liquid according to the present invention;

[0053] Figure 2 A schematic diagram of liquid flow direction in a process of removing lead and cadmium ions in a system for removing lead and cadmium ions from industrial waste liquid according to the present invention;

[0054] Figure 3 A schematic diagram of liquid flow during a resin regeneration process of a system for removing lead and cadmium ions from industrial waste liquid according to the present invention;

[0055] Figure 4 A schematic diagram of liquid flow during a resin transformation process of a system for removing lead and cadmium ions from industrial waste liquid according to the present invention;

[0056] Figure 5 A schematic diagram of liquid flow during a resin flushing process of a system for removing lead and cadmium ions from industrial waste liquid according to the present invention;

[0057] Figure 6 A schematic diagram of the steps of a method for removing lead and cadmium ions from industrial waste liquid according to the present invention;

[0058] Description of reference numerals:

[0059] 1. Raw water tank; 2. Security filter; 3. Resin tank; 4. Acid tank; 5. Alkali tank; 6. Water tank; 7. Raw water pump; 8. Regeneration pump; 9. Transformation pump; 10. Flushing pump; 11. First pressure gauge; 12. Second pressure gauge; 13. Third pressure gauge; 14. Fourth pressure gauge; 15. Fifth pressure gauge; 16. First waste liquid input solenoid valve; 17. Second waste liquid input solenoid valve; 18. Third waste liquid input solenoid valve; 19. Liquid outlet solenoid valve; 20. Cleaning valve; 21. Regeneration liquid outlet solenoid valve; 22. Regeneration liquid inlet solenoid valve; 25. Acid injection solenoid valve; 26. Alkali liquid Injection solenoid valve; 27, water injection valve; 28, first waste liquid injection pipe; 29, second waste liquid injection pipe; 30, resin tank outlet pipe; 31, resin tank injection pipe; 32, resin tank connecting pipe; 33, outlet pipe; 34, regeneration pipe; 35, acid injection pipe; 36, alkali injection pipe; 37, water injection pipe; 38, cleaning pipe; 39, regeneration liquid inlet pipe; 42, regeneration liquid discharge pipe; 43, acid discharge pipe; 44, acid discharge solenoid valve; 45, alkali discharge pipe; 46, alkali discharge solenoid valve; 47, water discharge pipe; 48, water discharge solenoid valve; 49, resin tank outlet solenoid valve. DETAILED DESCRIPTION

[0060] The present application is further described below in detail through specific embodiments in conjunction with the accompanying drawings.

[0061] In the description of this application: unless otherwise specified, the meaning of "plurality" is two or more. The terms "first", "second", "third", etc. in this application are intended to distinguish the objects referred to, and do not have special meanings in terms of technical connotations (for example, they should not be understood as emphasizing the importance or order, etc.). Expressions such as "including", "comprising", "having", etc. also mean "not limited to" (certain units, components, materials, steps, etc.).

[0062] The terms such as "upper", "lower", "left", "right", "middle", etc. used in this application are usually used to facilitate intuitive understanding by comparing with the accompanying drawings, and are not absolute limitations on the positional relationship in the actual product. Without departing from the technical concept disclosed in this application, changes in these relative positional relationships should also be regarded as the scope of this application.

[0063] A system for removing lead and cadmium ions from industrial waste liquid according to the present invention, Figure 1 As shown, a raw water tank 1 is provided. The raw water tank 1 is used to contain the industrial waste liquid to be treated. The raw water tank 1 is provided with a raw water pump 7.

[0064] At least one resin tank 3 , an acid liquid tank 4 , an alkali liquid tank 5 , a water tank 6 , a liquid outlet pipe 33 , an acid liquid discharge pipe 43 , an alkali liquid discharge pipe 45 , a water discharge pipe 47 and a regeneration pipe 34 are also provided.

[0065] The resin tank 3 is filled with resin, which is an ion exchange resin used to absorb lead and cadmium ions in industrial waste liquid, such as: CH-90 resin, The weakly acidic group of iminodiacetic acid contained in CH-90 heavy metal ion exchange resin is easily ionized into Na + Ions, heavy metal ions lead and cadmium ions contained in water and Na ionized by CH-90 ion exchange resin + Ion exchange is performed so that the heavy metal cations in the industrial wastewater are transferred to the resin, and the Na + The top and bottom of the resin tank 3 are respectively provided with a resin tank injection pipe 31 and a resin tank outlet pipe 30 connected to the inside thereof, and the bottom of the resin tank 3 is provided with an emptying valve for emptying the resin, that is, for draining the water for washing the resin.

[0066] The acid liquid tank 4 is used to contain the regeneration liquid, and the acid liquid tank 4 is provided with a regeneration pump 8; the alkali liquid tank 5 is used to contain the transformation liquid, and the alkali liquid tank 5 is provided with a transformation pump 9; the water tank 6 is used to contain the cleaning liquid, and the water tank 6 is provided with a flushing pump 10; the liquid outlet pipe 33 is used to discharge the liquid from which the lead and cadmium ions are removed; the acid liquid discharge pipe 43 is provided with an acid liquid discharge solenoid valve (44); the alkali liquid discharge pipe 45 is provided with an alkali liquid discharge solenoid valve 46; the water discharge pipe 47 is provided with a water discharge solenoid valve 48.

[0067] The raw water pump 7 is connected to the resin tank injection pipe 31 through the first waste liquid injection pipe 28, and a first waste liquid input solenoid valve 16 is provided on the first waste liquid injection pipe 28; the liquid outlet pipe 33 and the resin tank liquid outlet pipe 30 are connected; and a resin tank liquid outlet solenoid valve 49 is provided on the resin tank liquid outlet pipe 30 between the liquid outlet pipe 33 and the resin tank 3.

[0068] The regeneration pump 8 is connected to the regeneration pipe 34 through the acid injection pipe 35, the transformation pump 9 is connected to the alkali injection pipe 36, and the flushing pump 10 is connected to the water injection pipe 37; an acid injection solenoid valve 25 is provided in the acid injection pipe 35; an alkali injection solenoid valve 26 is provided in the alkali injection pipe 36; and a water injection valve 27 is provided in the water injection pipe 37.

[0069] The regeneration pipe 34 is connected to the resin tank liquid outlet pipe 30 between the resin tank liquid outlet solenoid valve 49 and the resin tank 3 through the regeneration liquid inlet pipe 39; the regeneration liquid inlet solenoid valve 22 is provided on the regeneration liquid inlet pipe 39.

[0070] The resin tank injection pipe 31 is connected to the acid solution discharge pipe 43 , the alkali solution discharge pipe 45 and the water discharge pipe 47 through the regeneration liquid discharge pipe 42 ; the regeneration liquid outlet solenoid valve 21 is provided in the regeneration liquid discharge pipe 42 .

[0071] By setting the raw water tank 1, the resin tank 3, the acid tank 4, the alkali tank 5 and the water tank 6, and the pipes connecting them, and the solenoid valves on the pipes, when the present application removes lead and cadmium ions: close the cleaning valve 20, the regeneration liquid outlet solenoid valve 21, and the regeneration liquid inlet solenoid valve 22; open the first waste liquid input solenoid valve 16, the resin tank liquid outlet solenoid valve 49, and the liquid outlet solenoid valve 19; turn on the raw water pump 7; the waste liquid is pumped out from the raw water tank 1, enters the resin tank 3 to remove lead and cadmium ions, and then flows out from the liquid outlet pipe 33;

[0072] When regenerating the resin: close the first waste liquid input solenoid valve 16, the resin tank outlet solenoid valve 49, the alkali liquid discharge solenoid valve 46, the water discharge solenoid valve 48, the alkali liquid injection solenoid valve 26 and the water injection valve 27; open the acid liquid injection solenoid valve 25, the regeneration liquid outlet solenoid valve 21 and the acid liquid discharge solenoid valve 44; start the regeneration pump 8, the regeneration liquid is pumped out from the acid liquid tank 4, enters the resin tank 3 to regenerate the resin, and is then discharged from the acid liquid discharge pipe 43;

[0073] When transforming the resin: close the first waste liquid input solenoid valve 16, the resin tank liquid outlet solenoid valve 49, the acid liquid discharge solenoid valve 44, the water discharge solenoid valve 48, the acid liquid injection solenoid valve 25 and the water injection valve 27; open the alkali liquid injection solenoid valve 26, the regeneration liquid outlet solenoid valve 21 and the alkali liquid discharge solenoid valve 46; start the transformation pump 9, the transformation liquid is pumped out from the alkali liquid tank 5, enters the resin tank 3 to transform the resin, and is then discharged from the alkali liquid discharge pipe 45;

[0074] When flushing the resin: close the first waste liquid input solenoid valve 16, the resin tank liquid outlet solenoid valve 49, the acid liquid discharge solenoid valve 44, the alkali liquid discharge solenoid valve 46, the acid liquid injection solenoid valve 25 and the alkali liquid injection solenoid valve 26; open the water injection valve 27, the regeneration liquid outlet solenoid valve 21 and the water discharge solenoid valve 48; start the flushing pump 10, the cleaning liquid is pumped out from the water tank 6, enters the resin tank 3 to flush the resin, and is then discharged from the water discharge pipe 48.

[0075] The present application has a simple structure, with fewer overall pipelines. The number of resin tanks 3 can be arbitrarily set according to production needs, and the footprint is small. The ion exchange resin is used, and the process operation is simple, which can be fully automated and save labor costs. The ions released into the water during the resin treatment are OH- and Na+, which are non-toxic and safe to use. Under normal circumstances, industrial waste liquid enters the resin and the produced water meets the standards, which is fast and efficient. Compared with sedimentation tanks, no infrastructure is required, only a pressure tank body is needed, which reduces costs.

[0076] Optionally, in order to remove suspended matter in the industrial waste liquid and ensure that the resin is not hardened, a security filter 2 is further included, the first waste liquid injection pipe 28 is connected to the security filter 2, and the security filter 2 is connected to the resin tank injection pipe 31 through the second waste liquid injection pipe 29; the second waste liquid injection pipe 29 is provided with a second waste liquid input solenoid valve 17. The industrial waste liquid first flows through the security filter 2 for filtration, and then flows into the resin tank 3.

[0077] Optionally, in order to clean the safety filter 2 , the regeneration pipe 34 is connected to the first waste liquid injection pipe 28 between the first waste liquid input solenoid valve 16 and the safety filter 2 through the cleaning pipe 38 , and a cleaning valve 20 is provided in the cleaning pipe 38 .

[0078] Preferably, the filtration accuracy of the security filter 2 is 5 μm. When the pressure of the security filter 2 reaches the pressure of the front-end raw water pump 7, the filter element needs to be replaced in time. Therefore, a second pressure gauge 12 is provided on the security filter 2 to monitor the pressure of the security filter 2 in real time.

[0079] Preferably, in order to monitor the pressure status of the system of the present application in real time, prevent accidents and ensure safe production, a first pressure gauge 11 is provided in the first waste liquid injection pipe 28; a third pressure gauge 13 is provided in the acid injection pipe 35; a fourth pressure gauge 14 is provided in the alkali liquid injection pipe 36; and a fifth pressure gauge 15 is provided in the water injection pipe 37.

[0080] Preferably, in practical applications, a liquid outlet solenoid valve 19 is provided in the liquid outlet pipe 33 to control the outflow of the liquid after the lead and cadmium ions are removed.

[0081] Preferably, the regeneration liquid used in this application is a 5% hydrochloric acid or sulfuric acid solution, the transformation liquid is a 5% sodium hydroxide solution, and the cleaning liquid is pure water or tap water. + With water X 2+ When the resin is saturated with adsorption, it is regenerated with 5% hydrochloric acid or sulfuric acid solution. + X adsorbed on the resin functional groups 2+ Carry out ion exchange to restore the exchange capacity of the resin. The reaction is as follows:

[0082] R2R-COOX+H + →R2R-COOH+X 2+

[0083] Then use sodium hydroxide to perform a second transformation:

[0084] R2R-COOH+NaOH→R2R-COONa+H20

[0085] The exchange rate increases with the increase of ion concentration. + Ions can turn X2+ The ions are replaced, thereby regenerating the resin.

[0086] In order to improve the production efficiency of the production line, more than two resin tanks 3 are generally provided, and multiple resin tanks 3 can be used to remove lead and cadmium ions, which can improve the removal efficiency and the degree of removal. At the same time, multiple resin tanks 3 can also be provided to perform resin regeneration operations, and the removal and regeneration operations are performed in rotation to ensure uninterrupted operations. The setting of multiple resins 3 can be achieved by performing corresponding pipeline layouts. The embodiment of the present application provides a pipeline connection for multiple resin tanks 3 to perform lead and cadmium ion removal operations, specifically: the resin tank liquid outlet pipe 30 of the previous resin tank 3 of the adjacent resin tank 3 in the multiple resin tanks 3 and the resin tank liquid injection pipe 31 of the next resin tank 3 are connected through the resin tank connecting pipe 32, and the resin tank connecting pipe 32 is provided with a third waste liquid input solenoid valve 18.

[0087] The embodiment of the present application also provides the working principle when two resin tanks 3 are connected in series, which is as follows:

[0088] Removal of lead and cadmium ions: Figure 2 As shown, the first waste liquid input solenoid valve 16, the second waste liquid input solenoid valve 17, the third waste liquid input solenoid valve 18, the resin tank liquid outlet solenoid valve 49 on the resin tank liquid outlet pipe 30 of the resin tank 3 close to the raw water tank 1, and the liquid outlet solenoid valve 19 are opened; the cleaning valve 20, the regeneration liquid outlet solenoid valve 21, the regeneration liquid inlet solenoid valve 22 and the resin tank liquid outlet solenoid valve 49 on the resin tank liquid outlet pipe 30 of the resin tank 3 far away from the raw water tank 1 are closed; the raw water pump 7 is started, and the waste liquid flows from the raw water tank 1 into the security filter 2 to be filtered, and then enters the first resin tank 3, and then enters the second resin tank 3 through the resin tank connecting pipe 32, and finally flows out from the liquid outlet pipe 33.

[0089] Recycled resin: Figure 3 As shown, open the acid injection solenoid valve 25, the regeneration liquid inlet solenoid valve 22, the regeneration liquid outlet solenoid valve 21 and the acid discharge solenoid valve 44; close the cleaning valve 20, the second waste liquid input solenoid valve 17, the alkali liquid discharge solenoid valve 46, the water discharge solenoid valve 48, the third waste liquid input solenoid valve 18, the resin tank liquid outlet solenoid valve 49, the alkali liquid injection solenoid valve 26 and the water injection valve 27; turn on the regeneration pump 8, the regeneration liquid enters the regeneration pipe 34 from the acid tank 4, then enters the two resin tanks 3, and finally flows out from the acid discharge pipe 43.

[0090] Transformation resin: Figure 4As shown, open the alkali liquid injection solenoid valve 26, the regeneration liquid inlet solenoid valve 22, the regeneration liquid outlet solenoid valve 21 and the alkali liquid discharge solenoid valve 46; close the cleaning valve 20, the second waste liquid input solenoid valve 17, the acid liquid discharge solenoid valve 44, the water discharge solenoid valve 48, the third waste liquid input solenoid valve 18, the resin tank liquid outlet solenoid valve 49, the acid liquid injection solenoid valve 25 and the water injection valve 27; start the transformation pump 9, the transformation liquid enters the regeneration pipe 34 from the alkali liquid tank 5, then enters the two resin tanks 3, and finally flows out from the alkali liquid discharge pipe 45.

[0091] Rinse resin: Figure 5 As shown, open the water injection valve 27, the regeneration liquid inlet electromagnetic valve 22, the regeneration liquid outlet electromagnetic valve 21 and the water discharge electromagnetic valve 48; close the cleaning valve 20, the second waste liquid input electromagnetic valve 17, the acid liquid discharge electromagnetic valve 44, the alkali liquid discharge electromagnetic valve 46, the third waste liquid input electromagnetic valve 18, the resin tank liquid outlet electromagnetic valve 49, the acid liquid injection electromagnetic valve 25 and the alkali liquid injection electromagnetic valve 26; turn on the flushing pump 10, the cleaning liquid enters the regeneration pipe 34 from the water tank 6, then enters the two resin tanks 3, and then flows out from the water discharge pipe 47. When flushing the resin again, the security filter 2 can also be flushed. At this time, it is only necessary to close the first waste liquid input electromagnetic valve 16, open the cleaning valve 20 and the second waste liquid input electromagnetic valve 17, that is, the resin can be cleaned and the security filter 2 can be flushed at the same time.

[0092] Based on the above-mentioned system for removing lead and cadmium ions from industrial waste liquid, the present application embodiment also provides a method for removing lead and cadmium ions from industrial waste liquid, such as Figure 6 As shown, the specific steps include:

[0093] S01: Turn on the raw water pump 7; inject the industrial wastewater containing lead and cadmium ions in the raw water tank 1 into the resin tank 3;

[0094] S02: The lead and cadmium ions in the industrial wastewater undergo ion exchange with the functional groups on the surface of the resin balls in the resin tank 3, and the lead and cadmium ions are adsorbed by the resin ball particles; the raw water from which the lead and cadmium ions have been removed is adjusted in pH value and then discharged into a qualified water pool for reuse;

[0095] S03: After the resin is saturated with adsorption, the raw water pump 7 is turned off; the regeneration pump 8 is turned on to acid-wash and regenerate the resin;

[0096] S04: Use the regeneration liquid at a preset flow rate and perform pickling for a preset time;

[0097] S05: Turn off the regeneration pump 8, turn on the flushing pump 10, and use the cleaning fluid at a preset flow rate for a preset time to flush;

[0098] S06: Turn off the flushing pump 10, turn on the transformation pump 9, and transform the resin;

[0099] S07: using the transformation fluid at a preset flow rate to perform transformation for a preset time;

[0100] S08: Turn off the transformation pump 9, turn on the flushing pump 10, and use the cleaning fluid at a preset flow rate for a preset time to flush;

[0101] S09: Turn off the flushing pump 10, open the drain valve, and drain the resin; after the resin is drained, enter the next lead and cadmium ion removal operation.

[0102] Preferably, the regeneration liquid in step S04 is a 5% hydrochloric acid or sulfuric acid solution, and the resin is acid-washed at a flow rate of 4BV / H for 30 minutes; the transformation liquid in step S07 is a 5% sodium hydroxide solution, and the resin is alkaline-washed at a flow rate of 48BV / H for 30 minutes; the cleaning liquids in step S05 and step S08 are both pure water or tap water, and the resin is flushed at a flow rate of 10BV / H for 30 minutes.

[0103] The above is a relatively specific and detailed description of the present application through general description and specific embodiments. It should be understood that, based on the technical concept of the present application, several conventional adjustments or further innovations can be made to these specific embodiments; however, as long as they do not deviate from the technical concept of the present application, the technical solutions obtained by these conventional adjustments or further innovations also fall within the scope of protection of the claims of the present application.

Claims

1. A system for removing lead and cadmium ions from industrial waste liquid, comprising a raw water tank (1); the raw water tank (1) is used to contain the industrial waste liquid to be treated; the raw water tank (1) is provided with a raw water pump (7), characterized in that: Also includes: At least one resin tank (3); the resin tank (3) is filled with resin; the resin is an ion exchange resin used to absorb lead and cadmium ions in the industrial waste liquid; the top and bottom of the resin tank (3) are respectively provided with a resin tank injection pipe (31) and a resin tank outlet pipe (30) connected to the inside thereof; the bottom of the resin tank (3) is provided with a drain valve used to drain the resin; An acid liquid tank (4) for containing regeneration liquid; the acid liquid tank (4) is provided with a regeneration pump (8); An alkali liquid tank (5) is used to contain the transformation liquid; the alkali liquid tank (5) is provided with a transformation pump (9); A water tank (6) for containing cleaning liquid; the water tank (6) is provided with a flushing pump (10); A liquid outlet pipe (33) for discharging the liquid from which the lead and cadmium ions are removed; an acid liquid discharge pipe (43); the acid liquid discharge pipe (43) is provided with an acid liquid discharge solenoid valve (44); an alkali liquid discharge pipe (45); the alkali liquid discharge pipe (45) is provided with an alkali liquid discharge solenoid valve (46); A water discharge pipe (47); the water discharge pipe (47) is provided with a water discharge solenoid valve (48); Regeneration tube (34); The raw water pump (7) is connected to the resin tank liquid injection pipe (31) through a first waste liquid injection pipe (28); the first waste liquid injection pipe (28) is provided with a first waste liquid input electromagnetic valve (16); the liquid outlet pipe (33) is connected to the resin tank liquid outlet pipe (30); the resin tank liquid outlet pipe (30) between the liquid outlet pipe (33) and the resin tank (3) is provided with a resin tank liquid outlet electromagnetic valve (49); The regeneration pump (8) is connected to the regeneration pipe (34) through an acid injection pipe (35), the transformation pump (9) is connected to the alkali injection pipe (36), and the flushing pump (10) is connected to the water injection pipe (37); the acid injection pipe (35) is provided with an acid injection solenoid valve (25); the alkali injection pipe (36) is provided with an alkali injection solenoid valve (26); and the water injection pipe (37) is provided with a water injection valve (27); The regeneration pipe (34) is connected to the resin tank liquid outlet pipe (30) between the resin tank liquid outlet electromagnetic valve (49) and the resin tank (3) through the regeneration liquid inlet pipe (39); the regeneration liquid inlet pipe (39) is provided with a regeneration liquid inlet electromagnetic valve (22); The resin tank injection pipe (31) is connected to the acid solution discharge pipe (43), the alkali solution discharge pipe (45) and the water discharge pipe (47) respectively through the regeneration liquid discharge pipe (42); the regeneration liquid discharge pipe (42) is provided with a regeneration liquid outlet electromagnetic valve (21); It also includes a safety filter (2); the first waste liquid injection pipe (28) is connected to the safety filter (2); the safety filter (2) is connected to the resin tank injection pipe (31) through a second waste liquid injection pipe (29); the second waste liquid injection pipe (29) is provided with a second waste liquid input electromagnetic valve (17); the regeneration pipe (34) is connected to the first waste liquid injection pipe (28) between the first waste liquid input electromagnetic valve (16) and the safety filter (2) through a cleaning pipe (38); the cleaning pipe (38) is provided with a cleaning valve (20); The regeneration liquid is a 5% hydrochloric acid or sulfuric acid solution; the transformation liquid is a 5% sodium hydroxide solution; and the cleaning liquid is pure water or tap water.

2. A system for removing lead and cadmium ions from industrial waste liquid according to claim 1, characterized in that: The safety filter (2) is provided with a second pressure gauge (12).

3. The system for removing lead and cadmium ions from industrial waste liquid according to claim 1, characterized in that: The first waste liquid injection pipe (28) is provided with a first pressure gauge (11); the acid liquid injection pipe (35) is provided with a third pressure gauge (13); the alkali liquid injection pipe (36) is provided with a fourth pressure gauge (14); and the water injection pipe (37) is provided with a fifth pressure gauge (15).

4. The system for removing lead and cadmium ions from industrial waste liquid according to claim 1, characterized in that: The liquid outlet pipe (33) is provided with a liquid outlet solenoid valve (19).

5. A system for removing lead and cadmium ions from industrial waste liquid according to any one of claims 1 to 4, characterized in that: The resin tank liquid outlet pipe (30) of the preceding resin tank (3) and the resin tank liquid injection pipe (31) of the succeeding resin tank (3) of adjacent resin tanks (3) among the plurality of resin tanks (3) are connected via a resin tank connecting pipe (32); the resin tank connecting pipe (32) is provided with a third waste liquid input electromagnetic valve (18).

6. A method for removing lead and cadmium ions from industrial waste liquid, characterized in that: The following steps are involved: S01: Turn on the raw water pump (7); inject the industrial wastewater containing lead and cadmium ions in the raw water tank (1) into the resin tank (3); S02: The lead and cadmium ions in the industrial wastewater undergo ion exchange with the functional groups on the surface of the resin balls in the resin tank (3), and the lead and cadmium ions are adsorbed by the resin ball particles; the raw water from which the lead and cadmium ions have been removed is adjusted in pH value and then discharged into a qualified water pool for reuse; S03: After the resin is saturated with adsorption, the raw water pump (7) is turned off; the regeneration pump (8) is turned on to acid-wash and regenerate the resin; S04: Use the regeneration liquid at a preset flow rate and perform pickling for a preset time; S05: Turn off the regeneration pump (8), turn on the flushing pump (10), and use the cleaning fluid at a preset flow rate for a preset time to flush; S06: Turn off the flushing pump (10), turn on the transformation pump (9), and transform the resin; S07: using the transformation fluid at a preset flow rate to perform transformation for a preset time; S08: Turn off the transformation pump (9), turn on the flushing pump (10), and use the cleaning fluid at a preset flow rate for a preset time to flush; S09: Turn off the flushing pump (10), open the drain valve, and drain the resin; after the resin is drained, enter the next lead and cadmium ion removal operation.

7. The method for removing lead and cadmium ions from industrial waste liquid according to claim 6, characterized in that: The regeneration liquid in step S04 is 5% hydrochloric acid or sulfuric acid solution, and the resin is acid-washed at a flow rate of 4BV / H for 30 minutes; the transformation liquid in step S07 is 5% sodium hydroxide solution, and the resin is alkaline-washed at a flow rate of 48BV / H for 30 minutes; the cleaning liquids in step S05 and step S08 are both pure water or tap water, and the resin is flushed at a flow rate of 10BV / H for 30 minutes.

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