Composite copper foil waste recovery system

Abstract

The composite copper foil waste recovery system comprises a dissolving unit, a filtering unit and a recycling unit, the dissolving unit comprises a dissolving kettle and a heating and heat preservation device wrapped around the dissolving kettle, the top of the dissolving kettle is provided with a first inlet and a second inlet, the bottom of the dissolving kettle is provided with an oxygenation mechanism, and the first inlet is communicated with the second inlet. The first inlet is used for receiving composite copper foil fragments, and the second inlet is used for injecting mixed acid liquor, so that the composite copper foil fragments are dissolved and leached in the dissolving kettle (1), and a crude copper sulfate solution is obtained; the filtering unit is used for receiving and filtering the crude copper sulfate solution from the dissolving unit to obtain a purified solution; and the recycling unit is used for receiving the purified solution from the filtering unit and outputting the purified solution which is detected to be qualified to a water plating line. The closed loop of'waste-renewable resources-production raw materials' is realized, the comprehensive benefit of treatment of each ton of waste is improved by more than 50% compared with that of sold, and the method has economic benefits (cost reduction), environmental benefits (waste reduction) and process feasibility.

Description

Technical Field

[0001] This utility model belongs to the field of composite copper foil recycling technology, and in particular relates to a composite copper foil waste recycling system. Background Technology

[0002] Composite copper foil is a novel current collector material. Using a polymer material as the substrate, metallic copper is deposited on both sides, creating a structure similar to a "sandwich." It is primarily composed of a copper-polymer-copper composite, achieving advantages such as lightweight, high safety, and low cost. It is mainly used in the production of composite copper foil waste containing substrates such as PET / PP / PI / PPS / PE from new energy batteries (especially lithium batteries) and flexible circuits. With the booming development of the new energy vehicle industry and the continuous advancement of energy storage technology, lithium batteries are used as core components, leading to a surge in demand for composite copper foil and making it an important direction for innovation in lithium battery materials.

[0003] Battery manufacturers and vehicle manufacturers are placing increasingly stringent demands on lithium battery materials, requiring high energy density, high safety, and improved efficiency. Against this backdrop, composite current collectors, as an innovative material design, have demonstrated significant potential in enhancing battery energy density due to their unique performance advantages, becoming a research hotspot in the industry. However, with the rapid increase in the use of composite copper foil, how to efficiently and environmentally separate and recycle the copper elements within it to achieve resource recycling and reduce environmental impact has become a pressing technical challenge. Utility Model Content

[0004] In view of the shortcomings of the prior art, the purpose of this utility model is to provide a composite copper foil waste recycling system. This system combines multiple processes to selectively separate the copper layer from the polymer substrate in the composite copper foil, ultimately forming a copper sulfate solution usable in water plating lines. This solves the problem of recycling and reusing waste composite copper foil.

[0005] To achieve the above and other related objectives, this utility model proposes a composite copper foil waste recycling system, comprising:

[0006] The dissolution unit includes a dissolution vessel and a heating and insulation device surrounding the dissolution vessel. The top of the dissolution vessel is provided with a first inlet and a second inlet. The second inlet is equipped with a static mixer. The bottom of the dissolution vessel is provided with an oxygen filling mechanism. The first inlet is used to receive composite copper foil fragments, and the second inlet is used to inject mixed acid solution, so that the composite copper foil fragments are dissolved and leached in the dissolution vessel to obtain crude copper sulfate solution.

[0007] A filtration unit is used to receive the crude copper sulfate solution from the dissolving unit and filter it to obtain a purified solution;

[0008] The recycling unit is used to receive the purified solution from the filtration unit, detect the purified solution, and output the qualified purified solution to the water plating line.

[0009] Waste collection unit for collecting and treating waste gas from the dissolution unit, the filtration unit and the reuse unit.

[0010] In one embodiment of the present invention, the oxygenation mechanism includes an oxygen flow sensor and a plurality of gas distribution pipes. The plurality of gas distribution pipes are arranged inside the conical bottom of the dissolving vessel. The bottoms of the plurality of gas distribution pipes are connected and connected to an external air inlet valve through the oxygen flow sensor. The extension direction of each gas distribution pipe is parallel to the generatrix of the conical bottom, and each gas distribution pipe is uniformly provided with air holes.

[0011] In one embodiment of the present invention, the dissolving unit further includes a material cage with an integral through hole, the material cage being spaced out and fitted onto the cylindrical upper part of the dissolving vessel.

[0012] In one embodiment of this utility model, a crude copper sulfate storage tank and a pH meter are also included. The crude copper sulfate storage tank is used to store the crude copper sulfate solution. The top of the crude copper sulfate storage tank is connected to the bottom of the dissolving vessel through a first discharge valve. The pH meter is installed on the bottom outlet pipeline of the crude copper sulfate storage tank.

[0013] In one embodiment of this utility model, the filtration unit includes a PP filter, a carbon filter, and an intermediate storage tank. The bottom of the PP filter is connected to the bottom of the crude copper sulfate storage tank via a crude copper sulfate purification pump. The top of the PP filter is connected to the top of the intermediate storage tank via a second discharge valve. The bottom of the intermediate storage tank is connected to the bottom of the carbon filter via an intermediate transfer pump.

[0014] In one embodiment of this utility model, the recycling unit includes a finished product storage tank and a densitometer. The top of the finished product storage tank is connected to the top of the carbon filter through a third discharge valve. The densitometer is installed on the bottom outlet pipeline of the finished product storage tank and is connected to an external water plating line through a copper sulfate finished product pump.

[0015] In one embodiment of this utility model, a first reflux line and a second reflux line are also included. One end of the first reflux line is connected to the top of the PP filter through a first reflux valve, and the other end is connected to the top outlet line of the crude copper sulfate storage tank. One end of the second reflux line is connected to the top of the carbon filter through a second reflux valve, and the other end is connected to the top outlet line of the intermediate storage tank.

[0016] In one embodiment of this utility model, a waste gas collection pipeline is also included. The waste gas collection pipeline includes four gas pipes arranged in parallel. One end of each of the four gas pipes corresponds to and is connected to the top of the waste copper mold dissolving kettle, the top of the crude copper sulfate storage tank, the intermediate storage tank and the top of the finished product storage tank, respectively. The other end of each of the four gas pipes is connected to a waste gas treatment device.

[0017] In one embodiment of the present invention, a viewing window is provided on the conical bottom of the dissolving vessel, and a drain valve is provided at the lower end of the conical bottom.

[0018] In one embodiment of this utility model, the inlet of the static mixer is connected to both a sulfuric acid solution pipeline and a copper plating bath solution pipeline.

[0019] This utility model includes at least the following beneficial technical effects:

[0020] This invention proposes a composite copper foil waste recycling system. Composite copper foil fragments react with a mixed acid in a dissolving tank. An oxygenation mechanism at the bottom of the tank allows for oxygenation, utilizing the upward force of the rising gas to achieve self-stirring, reducing energy consumption (by over 40%). The oxygenation level is adjustable, promoting copper foil oxidation and dissolution while preventing excessive foaming. The resulting crude copper sulfate solution, after filtration and testing, is fed into an electroplating line. Since the main components of the purified solution match the requirements of the copper plating bath, it can be directly reused after passing testing without additional adjustments. The purified solution replaces a portion of the newly purchased copper sulfate, reducing production costs (copper sulfate is a major raw material in electroplating, accounting for over 30% of costs) while simultaneously recycling a large amount of waste composite copper foil. Therefore, by reusing the purified solution to the water plating line and using the copper plating bath solution of the water plating line to dissolve the composite copper foil, a closed loop of "waste → recycled resources → production raw materials" is achieved. The comprehensive benefit of each ton of waste treated is more than 50% higher than that of selling it externally, which has economic benefits (cost reduction), environmental benefits (waste reduction) and process feasibility. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of a composite copper foil waste recycling system in one embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the structure of the dissolving vessel in one embodiment of the present invention;

[0024] Figure 3 This is a flowchart of a composite copper foil waste recycling method in one embodiment of the present invention.

[0025] Labeling Explanation: 1-Dissolving kettle, 11-Heating and insulation device, 12-Static mixer, 13-Gas distribution pipe, 14-Material cage, 15-Crude copper sulfate storage tank, 16-pH meter, 21-PP filter, 22-Carbon filter, 23-Intermediate storage tank, 24-Crude copper sulfate purification pump, 25-Intermediate transfer pump, 31-Finished product storage tank, 32-Density meter, 33-Copper sulfate finished product pump, 41-First reflux pipeline, 42-Second reflux pipeline, 50-Waste gas collection pipeline. Detailed Implementation

[0026] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model.

[0027] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of this utility model. Therefore, the drawings only show the components related to this utility model and are not drawn according to the actual number, shape and size of the components. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0028] Please see Figure 1 and Figure 2 As shown, this utility model proposes a composite copper foil waste recycling system, including a dissolving unit, a filtering unit, a recycling unit, and a waste collection unit. The dissolving unit includes a dissolving vessel 1 and a heating and insulation device 11 surrounding the dissolving vessel 1. The top of the dissolving vessel 1 is provided with a first inlet and a second inlet. A static mixer 12 is installed at the second inlet. The bottom of the dissolving vessel 1 is provided with an oxygen filling mechanism. The first inlet is used to receive composite copper foil fragments, and the second inlet is used to inject mixed acid solution, so that the composite copper foil fragments are dissolved and leached in the dissolving vessel 1 to obtain a crude copper sulfate solution. The filtering unit is used to receive the crude copper sulfate solution from the dissolving unit and filter it to obtain a purified solution. The recycling unit is used to receive the purified solution from the filtering unit, test the purified solution, and output the qualified purified solution to the water plating line.

[0029] It should be noted that an aqueous plating line is a complete production system for electroplating metal surfaces, depositing metal coatings (such as copper, nickel, and chromium) onto substrates (such as plastics and metals) using electrochemical methods. Its core components include: a copper plating tank (core equipment): containing the copper plating solution for copper layer deposition; a pretreatment tank: for degreasing, pickling, and other pretreatments; a post-treatment tank: for washing, passivation, and drying; and a circulation system: for filtering, heating, and pumping the plating solution.

[0030] It should be noted that the body of the dissolving vessel 1 is lined with a glass-lined inner layer. Glass lining, also known as enamel, is resistant to strong acids (H2SO4, HNO3) and temperatures ranging from -30°C to 200°C, preventing metal ion contamination. The upper part of the dissolving vessel 1 has a cylindrical structure, and the lower part has a conical structure. The diameter-to-height ratio of the cylindrical structure is 1:1.2~1.5, and the cone angle of the conical structure is 60°~75°, facilitating the settling and centralized discharge of residues and preventing accumulation and blockage.

[0031] Furthermore, a viewing window is provided on the conical bottom, and a drain valve is located at the lower end of the conical bottom. The viewing window is a double-layered pressure-resistant sight glass made of tempered borosilicate glass, with a temperature resistance of 150℃. The reaction status and residue amount inside the dissolving vessel 1 can be monitored in real time through the viewing window, and the drain valve (pneumatic butterfly valve + PTFE seal) can periodically discharge undissolved impurities (such as polymer substrate fragments).

[0032] It should be noted that the second inlet is equipped with a static mixer 12, and the mixed acid solution obtained by mixing through the static mixer 12 is injected into the dissolving vessel 1 to participate in the reaction. The mixed acid solution is composed of copper plating bath solution and 50% sulfuric acid solution mixed in equal mass ratio in the water plating line. Among them, the copper plating bath solution is the key chemical solution in the water plating line, and its main components are: copper sulfate (CuSO4) and copper ions (Cu). 2+ ), sulfuric acid (H2SO4), chloride ions (Cl) - ) and additives, etc. It is evident that the addition of mixed acid solution creates an acidic environment (high H₂). + (concentration) and Cu 2+ Its oxidizing properties can accelerate the dissolution of waste copper foil. The simplified reaction formula is: Cu + 2H₂O. + +Cu 2+ →2Cu + +H2O, oxygen is required to oxidize Cu + Return to Cu 2+ The oxygenation mechanism can provide oxygenation and oxidation to Cu during the reaction process at any time. + Return to Cu 2+ .

[0033] It should be noted that the heating and heat preservation device 11 can be a circulating water heating and heat preservation device 11, with its lower part connected to the circulating water inlet pipe and the hot water inlet pipe via valves, and its upper part connected to the circulating water return pipe and the hot water return pipe via valves. The constant temperature reaction temperature in the dissolving kettle 1 can be controlled at 60±2℃. The oxygenation and stirring time can be 4 hours. The static mixer 12 is a high-efficiency mixing device without moving parts. Through a specially designed internal unit structure (such as spiral blades, baffles, etc.), it utilizes fluid kinetic energy to achieve continuous and uniform mixing of multi-component media. In this utility model, sulfuric acid solution and copper plating bath solution of a water plating line are mixed evenly to form a mixed acid solution.

[0034] Therefore, this utility model provides a composite copper foil waste recycling system. The composite copper foil fragments react with mixed acid in the dissolving kettle 1, and oxygen can be introduced into the dissolving kettle 1 through an oxygenation mechanism arranged at the bottom of the dissolving kettle 1. The self-stirring is achieved by using the upward power of the gas, which reduces energy consumption (more than 40%). At the same time, the oxygenation amount is adjustable (10~30m³ / h). Oxygenation can promote the oxidation and dissolution of copper foil, and its reaction formula is: Cu + H2SO4 + O2 → CuSO4 + H2O. It can also avoid excessive foaming.

[0035] The crude copper sulfate solution obtained from the reaction is filtered and tested to ensure it meets standards before being passed through the water plating line. This is because the main component of the purified solution is (Cu). 2+ H2SO4, Cl - The requirements for the copper plating bath solution are consistent with those of the water plating line, and after passing the test (e.g., Cu...). 2+ Concentrations of 100-150 g / L and TOC ≤ 50 ppm can be directly reused without additional adjustments. The purified solution replaces a portion of newly purchased copper sulfate, reducing production costs (copper sulfate is a major raw material in electroplating, accounting for over 30% of costs) while simultaneously recycling a large amount of waste composite copper foil. Therefore, by reusing the purified solution in the water plating line and using the copper plating bath solution in the water plating line to dissolve the composite copper foil, a closed loop of "waste → recycled resources → production raw materials" is achieved. The overall revenue per ton of waste treated is more than 50% higher than that from external sales, combining economic benefits (cost reduction), environmental benefits (waste reduction), and technological feasibility.

[0036] In one embodiment of the present invention, the oxygenation mechanism includes an oxygen flow sensor and a plurality of gas distribution pipes 13. The plurality of gas distribution pipes 13 are arranged in the conical bottom of the dissolving vessel 1. The bottoms of the plurality of gas distribution pipes 13 are connected and connected to an external air inlet valve through the oxygen flow sensor. The extension direction of each gas distribution pipe 13 is parallel to the generatrix of the conical bottom, and each gas distribution pipe 13 is uniformly provided with air holes.

[0037] It should be noted that 3-8 air distribution pipes 13 can be installed. The material of the air distribution pipes 13 can be Hastelloy C276, which is resistant to chloride ion corrosion. The pore diameter of the air distribution pipes 13 can be 1-2 mm. The pressure of high-pressure oxygen or air introduced into the oxygenation mechanism can be 0.3-0.5 MPa, and the oxygenation rate can be adjusted from 10 to 30 m³ / h.

[0038] Furthermore, a pressure sensor and an oxygen flow sensor can be connected in series on the air intake line of the oxygenation mechanism to detect the air supply pressure and oxygen flow in real time, and adjust the air intake in a coordinated manner to ensure a stable dissolution rate.

[0039] In one embodiment of the present invention, the dissolving unit further includes a material cage 14 with an integral through hole, and the material cage 14 is disposed in a gap fit on the upper cylindrical part of the dissolving vessel 1.

[0040] It should be noted that the material cage 14 is an integrated through-hole design, using a 316L stainless steel welded frame (mesh diameter Φ5~10mm) to ensure that the waste copper foil is in full contact with the acid solution, while intercepting undissolved substrates (such as PP, PET, PI, PPS, PE, etc.); the top is equipped with a lifting ring to match the workshop crane or electric hoist, with a load capacity of ≥1 ton; the detachable base plate (quick-release buckle design) facilitates the centralized cleaning of substrate residues; the outer diameter of the material cage 14 is slightly smaller than the inner diameter of the dissolving vessel 1 (gap 50~100mm) to ensure smooth lifting and no dead corners in the flow of acid solution; the surface of the material cage 14 is coated with a PTFE coating, which can withstand an acidic environment of 80℃ (pH≤1).

[0041] In one embodiment of the present invention, a crude copper sulfate storage tank 15 and a pH meter 16 are also included. The crude copper sulfate storage tank 15 is used to store crude copper sulfate solution. The top of the crude copper sulfate storage tank 15 is connected to the bottom of the dissolving vessel 1 through a first discharge valve. The bottom outlet pipeline of the crude copper sulfate storage tank 15 is equipped with a pH meter 16.

[0042] It should be noted that the tank body of the crude copper sulfate storage tank 15 is made of PPH (homopolymer polypropylene) through rotational molding, and the flange interface is reinforced with PVDF. The crude copper sulfate storage tank 15 and the vertical dissolving vessel 1 can be matched in a 1:1.2 capacity ratio. It can be equipped with an immersion pH electrode (measuring range 0~14, hydrofluoric acid resistant type) and an air stirring pipe (air pressure 0.3MPa, to prevent copper salt deposition).

[0043] The pH meter 16 monitors the acidity / alkalinity (pH value) of the solution in real time. Because the reaction between copper foil and sulfuric acid in dissolving vessel 1 requires maintaining a strong acidity (pH usually <1), an abnormally high pH (e.g., >2) may indicate excessive sulfuric acid consumption (requiring acid replenishment) or incomplete reaction (residual undissolved copper). When pH >3, Cu... 2+ It is easily hydrolyzed to form Cu(OH)2 precipitate, leading to copper loss and pipe blockage.

[0044] In one embodiment of the present invention, the filtration unit includes a PP filter 21, a carbon filter 22 and an intermediate storage tank 23. The bottom of the PP filter 21 is connected to the bottom of the crude copper sulfate storage tank 15 via a crude copper sulfate purification pump 24. The top of the PP filter 21 is connected to the top of the intermediate storage tank 23 via a second discharge valve. The bottom of the intermediate storage tank 23 is connected to the bottom of the carbon filter 22 via an intermediate transfer pump 25.

[0045] It should be noted that the outer shell of PP filter 21 is made of PP (polypropylene) molding, and the filter element is made of multi-layer sintered PP fiber (precision 1~5μm); the treatment flow rate is 5~20m³ / h, and the number of filter elements is 4~12 (parallel detachable design); the working pressure is ≤0.6MPa, and the backwashing pressure is ≥0.8MPa; the inlet and outlet differential pressure alarm is triggered when the outlet differential pressure is ≥0.15MPa. The inner wall of intermediate storage tank 23 is polished (Ra≤0.8μm); the size is the same as that of crude copper sulfate storage tank 15, with a liquid level sensor (4~20mA signal output); equipped with a magnetic circulation pump (flow rate 10~30m³ / h, head 15m); the top is equipped with a breather valve + activated carbon adsorber (dustproof and anti-volatile). The shell of the carbon filter 22 is made of 304 stainless steel with PP lining. The filter layer is coconut shell activated carbon (particle size 1~3mm, iodine value ≥1000mg / g; diameter Φ600~1200mm, packing height 1.2~2m; design flow rate 8~12m / h, contact time ≥10min; pneumatic slag discharge valve at the bottom (periodic backflushing to discharge waste).

[0046] In one embodiment of the present invention, the recycling unit includes a finished product storage tank 31 and a densitometer 32. The top of the finished product storage tank 31 is connected to the top of the carbon filter 22 through a third discharge valve. The bottom outlet pipeline of the finished product storage tank 31 is equipped with a densitometer 32 and is connected to an external water plating line through a copper sulfate finished product pump 33.

[0047] It should be noted that the finished storage tank 31 is made of PE (polyethylene) rotational molding, with a temperature resistance of -40~60℃; the size is the same as the crude copper sulfate storage tank 15, and the conical bottom structure (inclination angle ≥15°) facilitates crystallization and sedimentation; it is equipped with an online density meter 32 (installed in the circulation pipeline, measuring range 1.0~1.5g / cm³, accuracy ±0.001).

[0048] The density meter 32 can monitor the density of the purified copper sulfate solution in real time and can be directly correlated with Cu. 2+ Concentration: Density of copper sulfate solution and Cu 2+The concentration is positively correlated with the solution content. Density feedback allows for rapid determination of whether the solution meets electroplating reuse standards (e.g., density 1.15-1.25 g / cm³). If the density is lower than the set value (e.g., excessive dilution), it automatically triggers the addition of concentrated copper sulfate solution; if it is too high (due to evaporation and concentration), it prompts for water replenishment. Therefore, it ensures a stable solution concentration delivered to the water plating line, avoiding issues caused by Cu content... 2+ Fluctuations can lead to uneven coating or poor adhesion.

[0049] In one embodiment of the present invention, a first reflux line 41 and a second reflux line 42 are also included. One end of the first reflux line 41 is connected to the top of the PP filter 21 through a first reflux valve, and the other end is connected to the top outlet line of the crude copper sulfate storage tank 15. One end of the second reflux line 42 is connected to the top of the carbon filter 22 through a second reflux valve, and the other end is connected to the top outlet line of the intermediate storage tank 23.

[0050] It should be noted that if the solution after PP filtration fails the test (e.g., turbidity > 5 NTU), it should be immediately returned to the crude copper sulfate storage tank 15 through the first reflux valve to avoid contaminating the downstream carbon filter 22. This prevents solid particles from clogging the pores of the carbon filter 22 and extends the life of the activated carbon. If the TOC exceeds the standard after passing through the carbon filter 22 (e.g., > 50 ppm), the solution should be returned to the intermediate storage tank 23 for secondary treatment to ensure complete removal of organic matter. Residual organic matter can cause blistering or poor adhesion of the coating; the reflux design eliminates this risk.

[0051] In one embodiment of this utility model, it also includes a waste gas collection pipeline 50, which includes four gas pipes arranged in parallel. One end of each of the four gas pipes corresponds to and is connected to the top of the waste copper mold dissolving kettle 1, the top of the crude copper sulfate storage tank 15, the intermediate storage tank 23 and the top of the finished product storage tank 31, respectively. The other end of each of the four gas pipes is connected to a waste gas treatment device.

[0052] It should be noted that the waste gas treatment device can be an acid mist absorption tower to treat SO2 and NO in the waste gas. x The treatment process ensures that the exhaust gas meets the GB 31573-2015 emission standards.

[0053] Please see Figure 3 As shown, to achieve the above-mentioned objectives and other related objectives, this utility model also includes a method for recycling composite copper foil waste, specifically comprising the following steps:

[0054] Waste composite copper foil is pressed into blocks and sliced ​​to obtain composite copper foil fragments;

[0055] The composite copper foil fragments are put into the dissolving vessel 1, and the mixed acid solution is introduced into the dissolving vessel 1. Then, oxygen is introduced into the bottom of the dissolving vessel 1 and stirred, so that the composite copper foil fragments dissolve and react under constant temperature conditions to obtain crude copper sulfate solution.

[0056] The crude copper sulfate solution is first filtered to remove fine solid residues, and then the dissolved organic matter is filtered to obtain a purified solution.

[0057] Add the purification solution to the water plating line according to the specified ratio.

[0058] In one embodiment of this utility model, the mixed acid solution is composed of copper plating bath solution of water plating line and 50% sulfuric acid solution mixed in equal mass ratio.

[0059] It should be noted that the static mixer 12 is a high-efficiency mixing device without moving parts. Through specially designed internal unit structures (such as spiral blades and baffles), it utilizes fluid kinetic energy to achieve continuous and uniform mixing of multi-component media. In this invention, sulfuric acid solution and copper plating bath solution from an aqueous plating line are respectively injected into the static mixer 12 and mixed uniformly to form a mixed acid solution.

[0060] This invention relates to the treatment of waste composite copper foil. The polymer substrate of the composite copper foil is PP, PET, PPS, PI, or PE. The total thickness of the composite copper foil is 4~50μm, and the thickness of a single copper layer is 600~3000nm. The specific process includes the following steps:

[0061] Step 1) Weigh 500±10kg of waste composite copper foil and bal it in a vertical hydraulic baler;

[0062] Step 2) Crush the composite copper foil block into sheet-like composite copper foil using a pulverizer, with the sheet size ranging from 1cm to 3cm.

[0063] Step 3) Put the crushed copper foil into the dissolving kettle 1 of the waste copper film, close the feeding port of the dissolving kettle 1, close the bottom discharge valve, close its sewage outlet, and open the top exhaust gas collection port; mix 2 tons each of copper plating bath solution and 50% sulfuric acid in a 1:1 ratio, mix them evenly through static mixer 12, and then put them into the dissolving kettle 1 from the top. Stop adding liquid when the liquid reaches 2 / 3 of the capacity.

[0064] Step 4) Turn on the oxygenation mechanism and hot water return valve, close the cold water return valve and cold water inlet valve, and turn on the hot water inlet valve. Control the temperature to be constant at 60±2℃. After oxygenation and stirring for 4 hours, stop oxygenation and let it stand for 20 minutes until the temperature cools to 20±5℃. Then, open the feeding port, use a funnel to clean the surface substrate and collect it until there is no substrate left. Then, close the hot water inlet valve and hot water return valve. Close the feeding port and open the drain valve to remove the residue deposited at the bottom of the dissolving tank 1. Observe through the observation window that the discharged solution is clear and free of particles, then close the drain valve. Open the first discharge valve to discharge the solution to the crude copper sulfate storage tank 15. After observing that it is empty, close the first discharge valve.

[0065] Step 5) When the copper sulfate level in the crude sulfuric acid storage tank reaches 2 / 3, turn on the crude copper sulfate purification pump 24 to filter the crude copper sulfate solution through the PP filter element. The purpose of this is to filter out fine residues in the solution, making the solution cleaner. After the filtered solution passes the test, it is transferred to the intermediate copper sulfate storage tank 23 to wait for carbon filtration. If the test fails, open the first reflux valve to return it to the crude copper sulfate storage tank 15. After the PP filter element is repaired, PP filtration is performed again.

[0066] Step 6) When the liquid level in the intermediate copper sulfate storage tank 23 reaches 2 / 3, open the second discharge valve to allow the copper sulfate solution in the intermediate copper sulfate storage tank 23 to pass through the carbon filter 22 for carbonization treatment. The purpose of the carbon filter 22 is to adsorb organic matter in the solution and prevent the organic matter from exceeding the standard. If the test is qualified, open the third discharge valve to transfer the purified liquid to the finished copper sulfate storage tank 31. If the test is unqualified, open the second return valve to return the liquid to the intermediate copper sulfate storage tank 23. The carbon filter 22 will be rectified and carbon filtered again.

[0067] Step 7) According to the proportion required for the production of the water plating line, the qualified finished copper sulfate is transferred to the water plating line for use through the finished copper sulfate pump 33;

[0068] Step 8) After rinsing and drying the collected substrate in a water tank, it can be packaged and sold.

[0069] In summary, the composite copper foil waste recycling system and method of this utility model features upgraded system safety, eliminates manual operation into the reactor, and avoids acid mist exposure and mechanical damage, conforming to GB / T standards. Standard 12801-2022 "Safety and Hygiene Requirements for Production Processes"; Efficiency is doubled, with a 50% reduction in single-operation cycle (traditional manual feeding requires machine shutdown for cleaning, while this design allows for seamless integration); multiple material cages (14 rotations) increase equipment utilization to over 90%; It achieves refined separation and recycling of waste composite copper foil and substrate, promoting a green recycling of all components; An oxygen-filled stirring mechanism replaces mechanical stirring, eliminating wear on transmission parts and reducing maintenance costs by 60%; An acid-resistant enamel dissolving kettle (1) equipped with a stirring and temperature control system ensures rapid and complete dissolution of composite copper foil (including polymer substrate) in a sulfuric acid + oxygen-filled system, achieving a copper recovery rate ≥99%, far exceeding traditional incineration or acid leaching processes, and yielding a high-purity product; PP filter 21 + carbon filter 22 provide dual purification, effectively removing suspended particles and organic impurities (such as PVD coating residue); the resulting copper sulfate solution meets GB / T 665-2007 electroplating grade standards (Cu). 2+ Purity ≥ 99.5%.

[0070] Visualized management and automated wastewater discharge enable seamless integration from waste to finished product, reducing intermediate transfer pollution and increasing production efficiency by over 40%, making it suitable for continuous production. Undissolved substrate residue boasts high purity (copper content <0.5%), allowing for direct regeneration to polymer recycling lines or sale as waste. Automated design with online pH monitoring and density feedback crystallization precisely controls reaction conditions, reducing acid and energy consumption and lowering operating costs by 30% compared to traditional processes. The system seamlessly integrates with existing environmental protection facilities (such as acid mist towers and wastewater treatment systems) on composite copper foil production lines, achieving a 35% reduction in hazardous waste at the source and avoiding secondary pollution risks from external disposal of copper-containing waste. Copper sulfate solution can be directly reused in electroplating or water plating processes, forming a closed loop of "waste-regeneration-production," increasing the overall revenue per ton of waste treated by over 50% compared to external sales. Therefore, this system and method are particularly suitable for composite copper foil manufacturers in fields such as new energy batteries and flexible circuits, significantly improving environmental compliance and economic benefits while achieving resource recycling.

[0071] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

[0072] Throughout this description, numerous specific details, such as examples of components and / or methods, are provided to provide a complete understanding of embodiments of the present invention. However, those skilled in the art will recognize that embodiments of the present invention may be practiced without one or more of these specific details or by other devices, systems, components, methods, parts, materials, components, etc. In other instances, well-known structures, materials, or operations have not been specifically shown or described in detail to avoid obscuring aspects of embodiments of the present invention.

[0073] Throughout this specification, references to "an embodiment," "an embodiment," or "a specific embodiment" mean that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention, but not necessarily in all embodiments. Therefore, the various representations of the phrases "in one embodiment," "in an embodiment," or "in a specific embodiment" in different places throughout the specification do not necessarily refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic of any specific embodiment of the present invention can be combined with one or more other embodiments in any suitable manner. It should be understood that other variations and modifications of the embodiments of the present invention described and illustrated herein may be based on the teachings herein and will be considered part of the spirit and scope of the present invention.

[0074] It should also be understood that one or more of the elements shown in the figures may be implemented in a more separate or more integrated manner, or may even be removed because they are inoperable in certain circumstances or provided because they may be useful for a particular application.

[0075] Furthermore, unless otherwise expressly stated, any arrows in the accompanying drawings should be considered illustrative only and not limiting. Additionally, unless otherwise stated, the term "or" as used herein is generally intended to mean "and / or". Where a term is anticipated to provide a separation or combination capability that is unclear, a combination of components or steps will also be considered as indicated.

[0076] As used herein and throughout the claims below, unless otherwise specified, “a” and “the” include the plural references. Similarly, as used herein and throughout the claims below, unless otherwise specified, “in” means “in” and “on”.

[0077] The above description of the embodiments shown in this utility model (including the content set forth in the abstract of the specification) is not intended to be an exhaustive enumeration or to limit the utility model to the precise forms disclosed herein. Although specific embodiments and examples of the utility model have been described herein for illustrative purposes only, various equivalent modifications are possible within the spirit and scope of the utility model, as will be recognized and understood by those skilled in the art. As indicated, these modifications can be made to the utility model in accordance with the above description of the embodiments described herein, and such modifications will be within the spirit and scope of the utility model.

[0078] This document has generally described the systems and methods in detail to aid in understanding the present invention. Furthermore, various specific details have been set forth to provide a general understanding of embodiments of the present invention. However, those skilled in the art will recognize that embodiments of the present invention can be practiced without one or more specific details, or using other devices, systems, accessories, methods, components, materials, parts, etc. In other instances, well-known structures, materials, and / or operations have not been specifically shown or described in detail to avoid obscuring aspects of embodiments of the present invention.

[0079] Therefore, although the present invention has been described herein with reference to specific embodiments thereof, freedom of modification, various changes and substitutions are also within the scope of the above disclosure, and it should be understood that in some cases, certain features of the present invention may be adopted without departing from the scope and spirit of the invention and without corresponding use of other features. Thus, many modifications can be made to adapt a particular environment or material to the essential scope and spirit of the present invention. The present invention is not intended to be limited to the specific terms used in the following claims and / or the specific embodiments disclosed as the best mode of carrying out the present invention, but the present invention will include any and all embodiments and equivalents falling within the scope of the appended claims. Therefore, the scope of the present invention will be determined only by the appended claims.

Claims

1. A composite copper foil waste recycling system, characterized in that, include: The dissolution unit includes a dissolution vessel (1) and a heating and heat preservation device (11) surrounding the dissolution vessel (1). The top of the dissolution vessel (1) is provided with a first inlet and a second inlet. The second inlet is equipped with a static mixer (12). The bottom of the dissolution vessel (1) is provided with an oxygen filling mechanism. The first inlet is used to receive composite copper foil fragments, and the second inlet is used to inject mixed acid solution so that the composite copper foil fragments are dissolved and leached in the dissolution vessel (1) to obtain crude copper sulfate solution. A filtration unit is used to receive the crude copper sulfate solution from the dissolving unit and filter it to obtain a purified solution; The recycling unit is used to receive the purified solution from the filtration unit, detect the purified solution, and output the qualified purified solution to the water plating line.

2. The composite copper foil waste recycling system according to claim 1, characterized in that, The oxygenation mechanism includes an oxygen flow sensor and multiple gas distribution pipes (13). The multiple gas distribution pipes (13) are arranged inside the conical bottom of the dissolving vessel (1). The bottoms of the multiple gas distribution pipes (13) are connected and connected to the air inlet valve through the oxygen flow sensor. The extension direction of each gas distribution pipe (13) is parallel to the generatrix of the conical bottom, and each gas distribution pipe (13) is uniformly provided with air holes.

3. The composite copper foil waste recycling system according to claim 1, characterized in that, The dissolving unit also includes a material cage (14) with an integral through hole, which is disposed in a gap fit on the upper cylindrical part of the dissolving vessel (1).

4. The composite copper foil waste recycling system according to claim 3, characterized in that, The dissolution unit also includes a crude copper sulfate storage tank (15) and a pH meter (16). The crude copper sulfate storage tank (15) is used to store the crude copper sulfate solution. The top of the crude copper sulfate storage tank (15) is connected to the conical bottom of the dissolution vessel (1) through a first discharge valve. The pH meter (16) is installed on the bottom outlet pipeline of the crude copper sulfate storage tank (15).

5. The composite copper foil waste recycling system according to claim 4, characterized in that, The filtration unit includes a PP filter (21), a carbon filter (22), and an intermediate storage tank (23). The bottom of the PP filter (21) is connected to the bottom of the crude copper sulfate storage tank (15) via a crude copper sulfate purification pump (24). The top of the PP filter (21) is connected to the top of the intermediate storage tank (23) via a second discharge valve. The bottom of the intermediate storage tank (23) is connected to the bottom of the carbon filter (22) via an intermediate transfer pump (25).

6. The composite copper foil waste recycling system according to claim 5, characterized in that, The recycling unit includes a finished product storage tank (31) and a densitometer (32). The top of the finished product storage tank (31) is connected to the top of the carbon filter (22) through a third discharge valve. The bottom of the finished product storage tank (31) is connected to an external water plating line through a copper sulfate finished product pump (33), and the densitometer (32) is installed on the connecting pipeline.

7. A composite copper foil waste recycling system according to claim 6, characterized in that, It also includes a first reflux line (41) and a second reflux line (42). One end of the first reflux line (41) is connected to the top of the PP filter (21) through a first reflux valve, and the other end is connected to the top outlet line of the crude copper sulfate storage tank (15). One end of the second reflux line (42) is connected to the top of the carbon filter (22) through a second reflux valve, and the other end is connected to the top outlet line of the intermediate storage tank (23).

8. The composite copper foil waste recycling system according to claim 7, characterized in that, It also includes a waste gas collection pipeline (50), which includes four gas pipes arranged in parallel. One end of each of the four gas pipes corresponds to and is connected to the top of the waste copper mold dissolving kettle (1), the top of the crude copper sulfate storage tank (15), the intermediate storage tank (23), and the top of the finished product storage tank (31). The other end of each of the four gas pipes is connected to a waste gas treatment device.

9. A composite copper foil waste recycling system according to claim 2, characterized in that, The melting vessel (1) has a viewing window on its conical bottom and a drain valve at the lower end of the conical bottom.

10. A composite copper foil waste recycling system according to claim 1, characterized in that, The inlet of the static mixer (12) is connected to the sulfuric acid solution pipeline and the copper plating tank solution pipeline, respectively.

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