Copper-containing wastewater recovery system and recovery method
By combining ultrasonic cavitation treatment with copper ion imprinted membranes, ultrafiltration membranes, and electrochemical reduction technology, the problem of poor copper recovery efficiency in existing technologies has been solved, achieving efficient and high-purity copper recovery while avoiding secondary pollution.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- TONGWEI SOLAR ENERGY (CHENGDU) CO LID
- Filing Date
- 2026-04-02
- Publication Date
- 2026-05-08
AI Technical Summary
In existing technologies, a large amount of copper in copper-containing wastewater generated by electroplating exists in a stable complexed state, which makes it impossible for the imprinted sites of copper imprinted polymers to fully capture copper ions, resulting in an adsorption capacity decay of more than 80% and poor recovery effect.
Wastewater is treated with ultrasonic cavitation using an ultrasonic reaction device to dissociate complexed copper into free copper ions, which are then captured by a copper ion imprinted membrane. Combined with ultrafiltration membrane filtration and electrochemical reduction regeneration technology, efficient recovery of copper ions is achieved.
It significantly improves copper recovery efficiency, with an adsorption capacity of 402 mg/m², a Cu²+/Zn²+ selectivity ratio greater than 1500:1, and a recovery purity of up to 99.95%, avoiding secondary pollution and maintaining efficient system operation.
Smart Images
Figure CN121990643A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of wastewater treatment technology, and more specifically, to a copper-containing wastewater recovery system and recovery method. Background Technology
[0002] In the photovoltaic production process, the wastewater generated during the electroplating process contains a large amount of copper. Currently, the main method used in the market is to use acrylic-based films grafted with copper-imprinted polymers to adsorb copper in copper-containing wastewater, thereby achieving copper recovery.
[0003] However, in copper-containing wastewater generated by electroplating, a large amount of copper exists in a stable complexed state, which makes it impossible for the imprinted sites of copper imprinted polymers to fully capture copper ions. As a result, the adsorption capacity decreases by more than 80%, and the recovery effect is poor. Summary of the Invention
[0004] The purpose of this invention is to provide a copper-containing wastewater recovery system, which has the advantage of better copper recovery effect.
[0005] Another objective of this invention is to provide a method for recovering copper-containing wastewater, which has the advantage of better copper recovery.
[0006] An embodiment of the present invention provides a technical solution: A copper-containing wastewater recovery system includes an ultrasonic reactor and a recovery device that are fluidly connected in sequence. The ultrasonic reactor is configured to perform ultrasonic cavitation treatment on the wastewater. The recovery device includes a copper ion imprinted membrane for capturing copper ions in the wastewater after ultrasonic cavitation treatment.
[0007] In an optional embodiment, the recovery device further includes an ultrafiltration membrane disposed upstream of the copper ion imprinted membrane for filtering the wastewater after ultrasonic cavitation treatment.
[0008] In an optional embodiment, the recovery device further includes a housing having a receiving space, in which both the copper ion imprinted membrane and the ultrafiltration membrane are disposed.
[0009] In an optional embodiment, the recovery device further includes an ultrasonic transducer installed within the accommodating space.
[0010] In an optional embodiment, the copper-containing wastewater recovery system further includes a reduction device, which includes a cathode and an anode spaced apart within the containment space, and a pulse power supply electrically connected to the cathode and the anode.
[0011] An embodiment of the present invention also provides a method for recovering copper-containing wastewater, comprising: Wastewater is treated with ultrasonic cavitation. Copper ion imprinting membranes were used to capture copper ions in wastewater after ultrasonic cavitation treatment.
[0012] In an optional embodiment, after the step of capturing copper ions in the wastewater after ultrasonic cavitation treatment using a copper ion imprinted membrane, the copper-containing wastewater recovery method further includes: Metallic copper is obtained by electrochemically reducing the copper ions captured by the copper ion imprinting membrane.
[0013] In an optional embodiment, during the electrochemical reduction process, a potential relative to the saturated calomel electrode is applied to the cathode. A pulse potential ranging from 0.6V to -1.0V.
[0014] In an optional embodiment, prior to the step of capturing copper ions in the wastewater after ultrasonic cavitation treatment using a copper ion imprinted membrane, the copper-containing wastewater recovery method further includes: Ultrafiltration membranes are used to filter wastewater that has undergone ultrasonic cavitation treatment.
[0015] In an optional embodiment, the copper-containing wastewater recovery method further includes: The ultrafiltration membrane and / or the copper ion imprinted membrane are ultrasonically cleaned using an ultrasonic transducer.
[0016] Compared to existing technologies, the copper-containing wastewater recovery system provided by this invention includes an ultrasonic reactor and a recovery device connected in sequence. The ultrasonic reactor is configured to perform ultrasonic cavitation treatment on the wastewater, and the recovery device includes a copper ion-imprinted membrane for capturing copper ions in the ultrasonically cavitated wastewater. In practical applications, the wastewater first undergoes ultrasonic cavitation treatment in the ultrasonic reactor, causing the complexed copper in the wastewater to dissociate into free copper ions. After completion, the wastewater flows into the recovery device, where the copper ion-imprinted membrane captures the copper ions. Because ultrasonic cavitation is used to dissociate the complexed copper before capturing the copper ions, the copper ion-imprinted membrane can fully capture the copper ions, significantly improving the recovery effect. Therefore, the beneficial effects of the copper-containing wastewater recovery system provided by this invention include: better copper recovery efficiency. Attached Figure Description
[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be considered as limiting the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0018] Figure 1 A structural block diagram of a copper-containing wastewater recovery system provided for an embodiment of the present invention; Figure 2 A flowchart illustrating a method for recovering copper-containing wastewater according to an embodiment of the present invention.
[0019] Icons: 100-Copper-containing wastewater recovery system; 110-Ultrasonic reaction device; 120-Recovery device; 121-Copper ion imprinted membrane; 122-Ultrafiltration membrane; 123-Shell; 1231-Containment space; 131-Cathode; 132-Anode; 140-Wastewater pool. Detailed Implementation
[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0021] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.
[0022] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0023] In the description of this invention, it should be understood that the terms "upper," "lower," "inner," "outer," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only used to facilitate the description of this invention and to simplify the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.
[0024] Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.
[0025] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, terms such as "set" and "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0026] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.
[0027] Example Please see Figure 1 , Figure 1 The diagram shown is a structural block diagram of the copper-containing wastewater recovery system 100 provided in this embodiment.
[0028] The copper-containing wastewater recovery system 100 provided in this embodiment includes an ultrasonic reaction device 110 and a recovery device 120, which are in fluid communication. The ultrasonic reaction device 110 is used to perform ultrasonic cavitation treatment on the wastewater to dissociate the complexed copper in the wastewater into free copper ions. The wastewater after ultrasonic cavitation treatment flows into the recovery device 120, which includes a copper ion imprinted membrane 121 capable of capturing copper ions in the wastewater and realizing copper recovery.
[0029] In this embodiment, the ultrasonic reaction device 110 includes a reaction tank for containing wastewater and a first ultrasonic transducer connected to the reaction tank. In practical applications, wastewater is introduced into the reaction tank, and the first ultrasonic transducer emits ultrasonic waves, which induce cavitation in the wastewater. When the cavitation collapses, energy is released, causing the complexed copper to dissociate.
[0030] Preferably, the first ultrasonic transducer in the ultrasonic reaction device 110 emits ultrasonic waves at a frequency of 26kHz to 30kHz, specifically 26kHz, 27kHz, 28kHz, 29kHz, or 30kHz. The ultrasonic power density in the wastewater is maintained between 0.3W / mL and 0.7W / mL, specifically 0.3W / mL, 0.4W / mL, 0.5W / mL, 0.6W / mL, or 0.7W / mL. After treating the wastewater in this ultrasonic field for 5-10 minutes, the dissociation rate of the complexed copper can reach over 98%.
[0031] In fact, the recovery device 120 in this embodiment also includes an ultrafiltration membrane 122. The ultrafiltration membrane 122 and the copper ion imprinted membrane 121 form a double membrane structure. The ultrafiltration membrane 122 is located upstream of the copper ion imprinted membrane 121. The wastewater after cavitation treatment passes through the double membrane structure composed of the ultrafiltration membrane 122 and the copper ion imprinted membrane 121 under an operating pressure difference of 0.05-0.1 MPa.
[0032] Ultrafiltration membrane 122, as the outer membrane in the double-layer membrane structure, first filters the wastewater after ultrasonic cavitation treatment. In this embodiment, a PVDF ultrafiltration membrane 122 with a molecular weight cutoff of 50 kDa is used, which can retain suspended particles and large molecular pollutants in the wastewater, preventing them from reaching the inner copper ion imprinted membrane 121 and causing blockage.
[0033] In this embodiment, the copper ion imprinted membrane 121 is a polyacrylamide membrane containing copper imprinted cavities. The diameter of the copper imprinted cavity is 0.24 nm to 0.28 nm, matching the hydration diameter of copper ions, thus achieving specific adsorption of free copper ions. The adsorption capacity reaches 402 mg / m², and Cu² + / Zn² + The selectivity ratio is greater than 1500:1.
[0034] In this embodiment, the recovery device 120 also includes a housing 123, which forms a receiving space 1231. Both the copper ion imprinted membrane 121 and the ultrafiltration membrane 122 are disposed within the receiving space 1231. In practical applications, the wastewater output from the ultrasonic reactor 110 passes through the double-layer membrane structure and is then contained within the receiving space 1231.
[0035] Furthermore, in this embodiment, the recovery device 120 also includes a second ultrasonic transducer installed in the accommodating space 1231. The array of the second ultrasonic transducer is installed at an angle of 12° to 15° with the membrane surface of the double-layer membrane structure. During the process of the ultrafiltration membrane 122 filtering wastewater and the copper ion imprinted membrane 121 capturing copper ions in the wastewater, the second ultrasonic transducer emits ultrasonic waves to form a standing wave field. The spacing between the standing wave nodes matches the pore size of the ultrafiltration membrane 122, thereby suppressing the fouling of the ultrafiltration membrane 122.
[0036] In practical applications, suspended solids in wastewater continuously impact the surface of the ultrafiltration membrane 122 and attempt to deposit. The cavitation jet generated by the ultrasonic standing wave washes the membrane surface in real time, preventing suspended solids from clogging the ultrafiltration membrane 122, so that the membrane flux retention rate of the ultrafiltration membrane 122 is greater than 95% (continuous operation for 200 hours).
[0037] The copper-containing wastewater recovery system 100 provided in this embodiment also includes a reduction device, which includes a cathode 131 and an anode 132 spaced apart in the accommodating space 1231, and a pulse power supply electrically connected to the cathode 131 and the anode 132.
[0038] In practical applications, once the copper ion imprinted membrane 121 is saturated with adsorbed copper ions, the system switches to regeneration mode, and the pulse power supply applies a potential relative to the saturated calomel electrode to the cathode 131. A pulse potential ranging from 0.6V to -1.0V, specifically... 0.6V 0.7V 0.8V 0.9V or 1.0V, pulse period of 10s, duty cycle of 15%–25%.
[0039] By employing the pulsed potential of the cathode 131, the degradation of the membrane material caused by excessive local reduction on the surface of the copper ion imprinted membrane 121 can be avoided. It also allows the desorbed copper ions sufficient time to diffuse to the surface of the cathode 131, preventing them from depositing on the surface of the copper ion imprinted membrane 121 and causing contamination. A duty cycle of 15%–25% is the balance value between efficient desorption and membrane protection.
[0040] The copper ions on the copper ion imprinted membrane 121 undergo electrochemical desorption via reduction at cathode 131 and are deposited as metallic copper on the surface of cathode 131. The purity of the recovered copper can reach 99.95%, and the metallic copper deposited on cathode 131 can be periodically stripped and collected. Compared with the acid washing and reduction of copper in the imprinted membrane in the prior art, the reduction process does not require the use of acidic reagents, avoids secondary pollution, and can run continuously for more than 500 cycles without significant performance degradation.
[0041] Furthermore, during the reduction process, the standing wave field formed by the second ultrasonic transducer remains continuously. The continuous ultrasonic action can promptly remove any small amount of incompletely desorbed copper, trace suspended matter that may remain on the double-layer membrane structure, as well as trace amounts of crystalline deposits that may be generated during the reduction and regeneration process. It also accelerates the mass transfer efficiency of copper ions from the copper ion imprinted membrane 121 to the cathode 131, thereby improving the reduction and regeneration efficiency.
[0042] In fact, the copper-containing wastewater recycling system 100 provided in this embodiment also includes a wastewater pool 140. After the reduction and regeneration are completed, the wastewater in the containment space 1231 is discharged into the wastewater pool 140 for collection.
[0043] In summary, the copper-containing wastewater recovery system 100 provided in this embodiment achieves the dissociation of complexed copper in the wastewater before adsorption using the ultrasonic reaction device 110, thereby improving the subsequent capture effect of copper ions. The ultrafiltration membrane 122 and the copper ion imprinted membrane 121 form a double-layer membrane structure, realizing the filtration and adsorption of wastewater before adsorption, which can effectively maintain the performance of the copper ion imprinted membrane 121. The electrochemical reduction and regeneration of copper avoids secondary pollution and achieves better regeneration effect. During the adsorption, capture and regeneration process, the standing wave field continuously formed in the recovery device 120 continuously operates, realizing the self-cleaning of the double-layer membrane and improving the reduction and regeneration efficiency.
[0044] In addition, this embodiment also provides a method for recovering copper-containing wastewater, which is applied to the aforementioned method for recovering copper-containing wastewater. Please refer to [link to previous document]. Figure 2 , Figure 2 The diagram shown is a flowchart of the copper-containing wastewater recovery method, which may include: Step S101: Perform ultrasonic cavitation treatment on the wastewater.
[0045] Understandably, ultrasonic cavitation treatment can be carried out in the ultrasonic reaction device 110. Specifically, the first ultrasonic transducer in the ultrasonic reaction device 110 emits ultrasonic waves at a frequency of 26 kHz to 30 kHz, maintaining the ultrasonic power density in the wastewater between 0.3 W / mL and 0.7 W / mL. After treating the wastewater in this ultrasonic field for 5-10 minutes, the dissociation rate of the complexed copper can reach over 98%.
[0046] Step S102: Use ultrafiltration membrane 122 to filter the wastewater after ultrasonic cavitation treatment.
[0047] Step S103: Copper ion imprinting membrane 121 is used to capture copper ions in the wastewater after ultrasonic cavitation treatment.
[0048] Ultrafiltration membrane 122 and copper ion imprinted membrane 121 form a double membrane structure. Ultrafiltration membrane 122 is located upstream of copper ion imprinted membrane 121. Wastewater after cavitation treatment passes through the double membrane structure composed of ultrafiltration membrane 122 and copper ion imprinted membrane 121 under an operating pressure difference of 0.05-0.1 MPa.
[0049] Ultrafiltration membrane 122, as the outer membrane in a bilayer membrane structure, filters wastewater treated by ultrasonic cavitation. Copper ion imprinted membrane 121 is a polyacrylamide membrane containing copper imprinted cavities with a cavity diameter of 0.24 nm to 0.28 nm, matching the hydration diameter of copper ions to achieve specific adsorption of free copper ions.
[0050] Step S104: Copper ions captured by the copper ion imprinting membrane are electrochemically reduced to obtain metallic copper.
[0051] When the copper ion imprinted membrane 121 becomes saturated with adsorbed copper ions, the system switches to regeneration mode, and the pulse power supply applies a potential relative to the saturated calomel electrode to the cathode 131. A pulse potential ranging from 0.6V to -1.0V with a duty cycle of 15%–25%.
[0052] Step S105: Ultrasonic cleaning is performed on the ultrafiltration membrane 122 and / or the copper ion imprinted membrane 121 using an ultrasonic transducer.
[0053] During steps S102 to S104, the standing field wave generated by the second ultrasonic transducer in the recovery device 120 continues to operate, achieving self-cleaning of the double-layer membrane structure and improving the reduction and regeneration efficiency.
[0054] In summary, the copper-containing wastewater recovery method provided in this embodiment utilizes ultrasonic cavitation treatment to dissociate the complexed copper in the wastewater before adsorption, thereby improving the subsequent capture effect of copper ions. The use of an ultrafiltration membrane 122 and a copper ion-imprinted membrane 121 for pre-filtration and subsequent adsorption effectively maintains the performance of the copper ion-imprinted membrane 121. Electrochemical reduction and regeneration of copper avoids secondary pollution while achieving better regeneration results. During the adsorption, capture, and regeneration processes, the standing wave field continuously operates, enabling self-cleaning of the double-layer membrane and improving the reduction and regeneration efficiency.
[0055] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A copper-containing wastewater recovery system, characterized in that, The device includes an ultrasonic reaction device (110) and a recovery device (120) connected in sequence by fluid. The ultrasonic reaction device (110) is configured to perform ultrasonic cavitation treatment on wastewater. The recovery device (120) includes a copper ion imprinted membrane (121) for capturing copper ions in the wastewater after ultrasonic cavitation treatment.
2. The copper-containing wastewater recovery system according to claim 1, characterized in that, The recovery device (120) also includes an ultrafiltration membrane (122), which is disposed upstream of the copper ion imprinted membrane (121) and is used to filter the wastewater after ultrasonic cavitation treatment.
3. The copper-containing wastewater recovery system according to claim 2, characterized in that, The recycling device (120) also includes a housing (123), which forms an accommodating space (1231), and the copper ion imprinted membrane (121) and the ultrafiltration membrane (122) are both disposed in the accommodating space (1231).
4. The copper-containing wastewater recovery system according to claim 3, characterized in that, The recovery device (120) also includes an ultrasonic transducer installed within the accommodating space (1231).
5. The copper-containing wastewater recovery system according to claim 3, characterized in that, The copper-containing wastewater recovery system (100) further includes a reduction device, which includes a cathode (131) and an anode (132) spaced apart in the accommodating space (1231), and a pulse power supply electrically connected to the cathode (131) and the anode (132).
6. A method for recovering copper-containing wastewater, characterized in that, include: Wastewater is treated with ultrasonic cavitation. Copper ion imprinted membrane (121) was used to capture copper ions in wastewater after ultrasonic cavitation treatment.
7. The method for recovering copper-containing wastewater according to claim 6, characterized in that, Following the step of capturing copper ions in the wastewater after ultrasonic cavitation treatment using a copper ion imprinted membrane (121), the copper-containing wastewater recovery method further includes: Metallic copper is obtained by electrochemical reduction of copper ions captured by the copper ion imprinted membrane (121).
8. The method for recovering copper-containing wastewater according to claim 7, characterized in that, During the electrochemical reduction process, a potential relative to the saturated calomel electrode is applied to the cathode (131). A pulse potential ranging from 0.6V to -1.0V.
9. The method for recovering copper-containing wastewater according to claim 6, characterized in that, Prior to the step of capturing copper ions in the wastewater after ultrasonic cavitation treatment using a copper ion imprinted membrane (121), the copper-containing wastewater recovery method further includes: Ultrafiltration membrane (122) was used to filter the wastewater after ultrasonic cavitation treatment.
10. The method for recovering copper-containing wastewater according to claim 9, characterized in that, The copper-containing wastewater recovery method also includes: The ultrafiltration membrane (122) and / or the copper ion imprinted membrane (121) are ultrasonically cleaned using an ultrasonic transducer.