A device and method for comprehensive recycling of copper-containing waste liquid

Abstract

The present invention provides a device and method for comprehensive recycling of copper-containing waste liquid. The device comprises: a copper-containing waste liquid storage tank, a filter, a cyclone electrowinning device, an electrocatalytic oxidation tank, a first filter press, a neutralization reactor, a fluidized displacement tower, a second filter press, and a ferrous sulfate storage tank connected in sequence, wherein the cyclone electrowinning device is used to control the electrowinning voltage according to the copper content to obtain the electrowinning residual liquid, the electrocatalytic oxidation tank is used to electrocatalytically oxidize the electrowinning residual liquid to remove some organic matter in the waste liquid, the neutralization reactor is used to neutralize the electrowinning residual liquid by adding a neutralizer, and adjust the pH value, and the fluidized displacement tower is used to fluidize the electrowinning residual liquid with the pH value adjusted by adding iron powder to replace the copper remaining in the solution, so as to obtain ferrous sulfate refined liquid. The present invention effectively separates and recycles metallic copper and removes impurities such as organic matter, while not introducing other impurities into the system, saving costs, and being environmentally friendly, thereby realizing the comprehensive recycling of copper-containing waste liquid, and is suitable for the comprehensive recycling of copper-containing waste liquid in the hazardous waste industry.

Description

Technical Field

[0001] The present invention relates to the field of hazardous waste resource utilization, and in particular, to a device and method for comprehensive recycling of copper-containing waste liquid. Background Art

[0002] During the processing of PCB circuit boards, a large amount of low-concentration copper-containing waste liquid will be generated in the micro-etching and pickling processes. Its main function is to micro-etch a certain amount of copper, clean the board surface, oxides, organic matter and other impurities, and form micro-etching waste liquid and pickling waste liquid after treatment. This type of waste liquid contains a certain amount of copper, high COD content, and some also contain a small amount of iron. It is difficult to recycle and treat, and direct discharge will cause serious pollution to the environment.

[0003] At present, low-concentration copper-containing waste liquid is often directly extracted by electrolysis, chemical precipitation, adsorption, metal replacement and other methods, and then the waste liquid is discharged. The above methods have the following main shortcomings: (1) Failure to achieve comprehensive recycling of copper-containing waste liquid. Most hazardous waste enterprises only focus on the recovery of copper, while the recovery and disposal of non-copper components such as acid in the waste liquid are relatively neglected; (2) Failure to more effectively realize the resource utilization of copper, which is prone to secondary pollution. Most domestic enterprises use chemical methods to recover copper and acid in copper-containing waste liquid, and copper is converted into hazardous waste - copper-containing sludge, causing secondary environmental pollution; (3) Although traditional electrolysis can recover some metallic copper by electrolytic deposition, the recovery rate and quality are low, and the benefits need to be improved; (4) Failure to effectively remove COD in copper-containing waste liquid, can not improve the quality of copper and waste acid products, nor can it increase the added value of products.

[0004] Therefore, how to effectively remove COD, more efficiently recover copper and realize the comprehensive recycling of waste acid in the process of copper-containing waste liquid disposal, ensure product quality and increase added value has become the key to realizing the comprehensive recycling of copper-containing waste liquid. It is necessary to propose a comprehensive recycling device and method for copper-containing waste liquid to solve the above problems. Summary of the invention

[0005] A series of simplified concepts are introduced in the Summary of the Invention, which will be further described in detail in the Detailed Description of the Invention. The Summary of the Invention does not mean to attempt to define the key features and essential technical features of the claimed technical solution, nor does it mean to attempt to determine the scope of protection of the claimed technical solution.

[0006] In view of the shortcomings of the prior art, the present invention proposes a device and method for comprehensive recycling of copper-containing waste liquid. The device comprises: a copper-containing waste liquid storage tank, a filter, a cyclone electrowinning device, an electrocatalytic oxidation tank, a first filter press, a neutralization reactor, a fluidized displacement tower, a second filter press, and a ferrous sulfate storage tank connected in sequence, wherein the copper-containing waste liquid storage tank is used to collect copper-containing waste liquid, the filter is used to filter impurities, the cyclone electrowinning device is used to control the electrowinning voltage according to the copper content to obtain electrowinning residual liquid, the electrocatalytic oxidation tank is used to electrocatalytically oxidize the electrowinning residual liquid to remove part of the organic matter in the waste liquid, the first filter press is used to further filter impurities, the neutralization reactor is used to neutralize the electrowinning residual liquid by adding a neutralizer and adjust the pH value, the fluidized displacement tower is used to fluidize the electrowinning residual liquid with the adjusted pH value by adding iron powder to replace the copper remaining in the solution, the second filter press is used to filter the iron powder remaining in the solution and the replaced copper powder, and the ferrous sulfate storage tank is used to store the filtered solution, i.e., ferrous sulfate refined liquid.

[0007] Optionally, the device further comprises a replacement liquid overflow storage tank, which is connected between the fluidized displacement tower and the second filter press and is used to temporarily store the solution overflowing from the upper part of the fluidized displacement tower.

[0008] Optionally, the device also includes an electrolytic solution circulation tank, which is connected between the filter and the cyclone electrolytic device and is used to circulate the electrolytic residual liquid through the cyclone electrolytic device to obtain the electrolytic residual liquid with a copper content of less than 300 mg / L.

[0009] Optionally, the device further comprises a filtrate storage tank, which is connected between the first filter press and the neutralization reactor and is used for temporarily storing the electrodeposition residual liquid.

[0010] Optionally, the neutralizing agent is one of iron oxide or iron hydroxide, and the neutralization end point is pH=1-2.

[0011] Optionally, the iron powder has a mesh size of not less than 200 meshes.

[0012] A method for comprehensive recovery and utilization of copper-containing waste liquid, the method adopts the above-mentioned device for comprehensive recovery and utilization of copper-containing waste liquid, and the method comprises:

[0013] S1, the waste liquid is transferred from the copper-containing waste liquid storage tank to the cyclone electrowinning device after passing through the filter to obtain cathode copper;

[0014] S2, using electrocatalytic oxidation reaction to remove some organic matter in the waste liquid, and electrolyze to recover copper, and control the electrolytic voltage according to the copper content;

[0015] S3, the residual liquid from the electrolysis is transferred to the electrocatalytic oxidation tank for further electrocatalytic oxidation, and after the organic matter is removed, the impurities are filtered out through the first filter press and transferred to the neutralization reactor;

[0016] S4, adding a neutralizing agent to neutralize the electrodeposition residual solution, adjusting the pH and transferring to a fluidized displacement tower, and adding iron powder to fluidize and replace the residual copper in the solution;

[0017] S5, the second filter press filters the residual iron powder in the solution, and the copper powder settles and enriches at the bottom of the fluidized bed displacement tower after displacement, and is filtered through the second filter press to obtain the copper powder;

[0018] S6. The filtrate is the refined ferrous sulfate liquid, which is temporarily stored in a ferrous sulfate storage tank as a raw material for producing ferrous sulfate or polymerized ferrous sulfate.

[0019] Optionally, direct current is passed through the electrocatalytic oxidation tank, and the voltage is controlled at 3V-10V. After the hydrogen peroxide in the copper-containing waste liquid is fully utilized, a small amount of hydrogen peroxide is gradually added to participate in the reaction, so as to effectively degrade organic matter through electrocatalytic oxidation.

[0020] Optionally, the voltage of the cyclone electrowinning device is controlled at 1.8V-2.5V, and the electrowinning endpoint is that the copper content of the copper-containing waste liquid is ≤300mg / L.

[0021] Optionally, the fluidized displacement tower adopts countercurrent displacement, wherein the iron powder and the copper-containing waste liquid are continuously fed and discharged, and the feeding speed ratio of the iron powder and the copper-containing waste liquid is 0.29kg-0.35kg iron powder: 1L copper-containing waste liquid.

[0022] The present invention provides a device and method for comprehensive recycling of copper-containing waste liquid, which can effectively separate and recycle metallic copper and remove impurities such as organic matter, while not introducing other impurities into the system, saving costs and being environmentally friendly, thereby achieving comprehensive recycling of copper-containing waste liquid and being suitable for comprehensive recycling of copper-containing waste liquid in hazardous waste industries. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The following drawings of the present invention are used as part of the present invention for understanding the present invention. The drawings show embodiments of the present invention and their descriptions, and are used to explain the device and principle of the present invention. In the drawings,

[0024] Figure 1 A schematic structural diagram of a device for comprehensive recycling of copper-containing waste liquid according to an embodiment of the present invention;

[0025] Figure 2 A schematic structural diagram of a device for comprehensive recycling of copper-containing waste liquid according to an embodiment of the present invention;

[0026] Figure 3 A schematic structural diagram of a device for comprehensive recycling of copper-containing waste liquid according to an embodiment of the present invention;

[0027] Figure 4 A schematic structural diagram of a device for comprehensive recycling of copper-containing waste liquid according to an embodiment of the present invention;

[0028] Figure 5 A flow chart of a method for comprehensive recovery and utilization of copper-containing waste liquid according to the present invention;

[0029] Among them: 1—copper-containing waste liquid storage tank;

[0030] 2, 6, 9—centrifugal pump;

[0031] 3—Filter;

[0032] 4—cyclone electrowinning device;

[0033] 5—Electrocatalytic oxidation tank;

[0034] 7—First filter press;

[0035] 8—filtrate storage tank;

[0036] 10—Neutralization reactor;

[0037] 11, 14, 15, 18—Mortar pumps;

[0038] 12—fluidized displacement tower;

[0039] 13—Displacement fluid overflow tank;

[0040] 16—Second filter press;

[0041] 17—ferrous sulfate storage tank;

[0042] 19—Electrolytic liquid circulation tank. DETAILED DESCRIPTION

[0043] In the following description, a large number of specific details are provided to provide a more thorough understanding of the present invention. However, it is apparent to those skilled in the art that the present invention can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present invention, some technical features well known in the art are not described.

[0044] In order to fully understand the present invention, detailed steps will be presented in the following description to illustrate the structure proposed by the present invention. Obviously, the implementation of the present invention is not limited to the specific details familiar to those skilled in the art. The preferred embodiments of the present invention are described in detail below, but in addition to these detailed descriptions, the present invention may also have other embodiments.

[0045] It should be understood that when the terms "include" and / or "comprises" are used in this specification, they indicate the existence of the stated features, integers, steps, operations, elements and / or components, but do not exclude the existence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0046] At present, copper is often extracted directly from this low-concentration copper-containing waste liquid through electrolysis, chemical precipitation, adsorption, metal replacement and other methods, and then the waste liquid is discharged.

[0047] (1) Chemical precipitation is still mainly based on end-of-pipe treatment. Since the recovery value of low-concentration copper-containing wastewater such as micro-etching liquid and pickling is relatively small, most companies include it in the harmless treatment and wastewater system, and use traditional chemical precipitation, flocculation precipitation and other methods to treat general industrial wastewater and then discharge it in compliance with the standards, and then transfer the resulting copper-containing sludge or copper sludge to relevant recycling and treatment units. These methods require a large amount of reagents during the treatment process, increasing the burden and cost of wastewater treatment, and ultimately produce a large amount of copper sludge, failing to better realize the resource utilization of copper.

[0048] (2) The electrolysis method is widely used because it can recover copper ions. However, the current electrolysis method has some shortcomings in treating wastewater, such as low electrolysis efficiency, incomplete copper ions, complex management, or failure to effectively recover and utilize waste acid after electrolysis, and failure to achieve comprehensive recovery and utilization of waste liquid.

[0049] The copper recovery device for copper-containing waste liquid effectively improves the copper recovery rate, reduces costs and alleviates environmental pressure through the treatment of electrolytic cells, circulation tanks and cyclone electrolysis devices. The copper ion concentration of copper-containing waste liquid is 20g / L-80h / L. After direct electrolysis, the copper ion concentration drops to about 5g / L, and then enters the cyclone electrolysis device for electrolytic treatment. After treatment, the copper ion concentration drops to below 0.2g / L.

[0050] In a cyclone electrolysis device for copper-containing waste liquid, the polarization of electrolysis concentration difference is reduced by a cyclone electrolysis method, thereby improving the electrolysis efficiency.

[0051] However, the current electrolysis method has some shortcomings in treating copper-containing waste liquid, such as low electrolysis efficiency, incomplete copper recovery, complex management, or failure to remove organic matter, resource utilization of waste acid, and inability to achieve comprehensive recycling of waste liquid.

[0052] (3) The ion exchange method is a relatively environmentally friendly wastewater treatment technology available. Copper ions are replaced from waste liquid by ion exchange. However, due to the limitations of process and equipment, this method currently has the disadvantages of adding alkali to adjust the pH when recovering copper in the solution, producing a large amount of high-salt waste liquid, not treating organic matter, and not recycling waste acid. In addition, a large amount of wash water is produced.

[0053] (4) Metal replacement method: The metal replacement method is based on the difference in metal activity. The more active iron powder or aluminum powder is added to the copper-containing waste liquid to reduce the copper ions to sponge copper. Improper control of the replacement process of this method can easily lead to a low copper recovery rate, and the sponge copper obtained has a low purity. There is still a large amount of sulfuric acid, COD and a certain amount of copper in the waste liquid. Direct discharge will cause secondary pollution to the environment;

[0054] In one embodiment, liquid caustic soda is added to copper-containing waste liquid to adjust the pH to 2-5; reverse osmosis is then used to concentrate the concentrated water, and Fenton reagent is added to carry out Fenton reaction to reduce COD; aluminum is used for substitution to obtain copper powder, and aluminum sulfate substitution liquid is obtained at the same time; the aluminum sulfate solution is matured and polymerized to obtain polyaluminum sulfate and prepare a composite aluminum sulfate solution.

[0055] The above patented method uses liquid alkali for neutralization to obtain sodium sulfate which enters the product, ultimately resulting in low product quality; using a reverse osmosis membrane to concentrate copper-containing waste liquid, the content of heavy metals such as copper and organic matter in the waste liquid is too high, which will greatly reduce the service life of the module.

[0056] Therefore, how to effectively remove COD, more efficiently recover copper and realize the comprehensive recycling of waste acid in the process of copper-containing waste liquid disposal, ensure product quality and increase added value, has become the key to realizing the comprehensive recycling of copper-containing waste liquid.

[0057] The present invention provides an environmentally friendly method for effectively separating and recovering metallic copper and removing impurities such as organic matter without introducing other impurities into the system, thereby realizing the comprehensive recovery and utilization of copper-containing waste liquid, and is suitable for the comprehensive recovery and utilization of copper-containing waste liquid in the hazardous waste industry.

[0058] The device and method for comprehensive recovery and utilization of copper-containing waste liquid of the present invention are further described below in conjunction with the accompanying drawings.

[0059] like Figure 1As shown, in one embodiment, the device includes a copper-containing waste liquid storage tank 1, a filter 3, a cyclone electrowinning device 4, an electrocatalytic oxidation tank 5, a first filter press 7, a neutralization reactor 10, a fluidized displacement tower 12, a second filter press 16, and a ferrous sulfate storage tank 17, which are connected in sequence. The waste liquid is transferred from the copper-containing waste liquid storage tank 1 to the cyclone electrowinning device 4 after passing through the bag filter 3 by a centrifugal pump 2. The hydrogen peroxide in the copper-containing waste liquid is used to participate in the electrocatalytic oxidation reaction to remove part of the organic matter in the waste liquid, and copper is electrolyzed to recover copper. The electrowinning voltage is controlled according to the copper content, and the copper content of the electrowinning residual liquid is finally controlled to be less than 300 mg / L. The residual liquid from the electrolysis is transferred to the electrocatalytic oxidation tank 5 for further electrocatalytic oxidation. After the organic matter is removed, the centrifugal pump 6 is pumped to the first filter press 7 to filter out impurities. The sludge impurities are outsourced for treatment and transferred to the neutralization reactor 10 through the centrifugal pump 9. Iron oxide or iron hydroxide is added to neutralize the sulfuric acid in the residual liquid from the electrolysis. After the pH is adjusted to 1-2, it is pumped to the fluidized displacement tower 12 with a mortar pump 11. At the same time, iron powder is gradually added from the top of the tower to countercurrent fluidize the residual copper in the solution. After deep displacement, the mortar pump 14 is used to pump to the second filter press 16 to filter the residual iron powder in the solution. The filtrate is the refined ferrous sulfate liquid, which is temporarily stored in the refined ferrous sulfate liquid storage tank 17 and pumped to the transport tank with a mortar pump 18 as a raw material for producing ferrous sulfate or polymerized ferrous sulfate. After the displacement, the copper powder is precipitated and enriched at the bottom of the tower and is pumped to the second filter press 16 by a mortar pump 15 to obtain the copper powder.

[0060] like Figure 2 As shown, in one embodiment, the device includes a copper-containing waste liquid storage tank 1, a filter 3, a cyclone electrowinning device 4, an electrocatalytic oxidation tank 5, a first filter press 7, a neutralization reactor 10, a fluidized displacement tower 12, a displacement liquid overflow storage tank 13, a second filter press 16, and a ferrous sulfate storage tank 17, which are connected in sequence. The waste liquid is transferred from the copper-containing waste liquid storage tank 1 to the cyclone electrowinning device 4 after passing through the bag filter 3 by a centrifugal pump 2. The hydrogen peroxide in the copper-containing waste liquid is used to participate in the electrocatalytic oxidation reaction to remove part of the organic matter in the waste liquid, and copper is electrolyzed to recover copper. The electrowinning voltage is controlled according to the copper content, and the copper content of the electrowinning residual liquid is finally controlled to be less than 300 mg / L. The residual liquid from the electrolysis is transferred to the electrocatalytic oxidation tank 5 for further electrocatalytic oxidation. After the organic matter is removed, the centrifugal pump 6 is pumped to the first filter press 7 to filter out impurities. The sludge impurities are outsourced for treatment and transferred to the neutralization reactor 10 through the centrifugal pump 9. Iron oxide or iron hydroxide is added to neutralize the sulfuric acid in the residual liquid from the electrolysis. After the pH is adjusted to 1-2, it is pumped to the fluidized displacement tower 12 with a mortar pump 11. At the same time, iron powder is gradually added from the top of the tower to countercurrently fluidize and replace the copper remaining in the solution. After deep replacement, the solution is temporarily stored in the replacement liquid overflow storage tank 13, and the mortar pump 14 is used to pump to the second filter press 16 to filter the residual iron powder in the solution. The filtrate is the refined ferrous sulfate solution, which is temporarily stored in the refined ferrous sulfate solution storage tank 17, and the mortar pump 18 is pumped to the transport tank as a raw material for producing ferrous sulfate or polyferrous sulfate. After the replacement, the copper powder is precipitated and enriched at the bottom of the tower, and is pumped to the second filter press 16 by a mortar pump 15 to obtain the copper powder.

[0061] like Figure 3 As shown, in one embodiment, the device includes a copper-containing waste liquid storage tank 1, a filter 3, a cyclone electrolysis device 4, an electrocatalytic oxidation tank 5, a first filter press 7, a neutralization reactor 10, a fluidized displacement tower 12, a displacement liquid overflow storage tank 13, a second filter press 16, and a ferrous sulfate storage tank 17, which are connected in sequence. The waste liquid is transferred from the copper-containing waste liquid storage tank 1 through a bag filter 3 and then through an electrolysis liquid circulation tank 19 to the cyclone electrolysis device 4. The hydrogen peroxide in the copper-containing waste liquid is used to participate in the electrocatalytic oxidation reaction to remove part of the organic matter in the waste liquid, and copper is electrolyzed to recover the copper. The electrolysis voltage is controlled according to the copper content. The electrolysis liquid circulation tank 19 is used to circulate the electrolysis residual liquid through the cyclone electrolysis device until the copper content of the electrolysis residual liquid is finally controlled to be less than 300 mg / L. The residual liquid from the electrolysis is transferred to the electrocatalytic oxidation tank 5 for further electrocatalytic oxidation. After the organic matter is removed, the centrifugal pump 6 is pumped to the first filter press 7 to filter out impurities. The sludge impurities are outsourced for treatment and transferred to the neutralization reactor 10 through the centrifugal pump 9. Iron oxide or iron hydroxide is added to neutralize the sulfuric acid in the residual liquid from the electrolysis. After the pH is adjusted to 1-2, it is pumped to the fluidized displacement tower 12 with a mortar pump 11. At the same time, iron powder is gradually added from the top of the tower to countercurrently fluidize and replace the copper remaining in the solution. After deep replacement, the solution is temporarily stored in the replacement liquid overflow storage tank 13, and the mortar pump 14 is used to pump to the second filter press 16 to filter the residual iron powder in the solution. The filtrate is the refined ferrous sulfate solution, which is temporarily stored in the refined ferrous sulfate solution storage tank 17, and the mortar pump 18 is pumped to the transport tank as a raw material for producing ferrous sulfate or polyferrous sulfate. After the replacement, the copper powder is precipitated and enriched at the bottom of the tower, and is pumped to the second filter press 16 by a mortar pump 15 to obtain the copper powder.

[0062] like Figure 4As shown, in one embodiment, the device includes a copper-containing waste liquid storage tank 1, a filter 3, a cyclone electrowinning device 4, an electrocatalytic oxidation tank 5, a first filter press 7, a filtrate storage tank 8, a neutralization reactor 10, a fluidized displacement tower 12, a displacement liquid overflow storage tank 13, a second filter press 16, and a ferrous sulfate storage tank 17, which are connected in sequence. The waste liquid is transferred from the copper-containing waste liquid storage tank 1 through a bag filter 3 and then through an electrowinning liquid circulation tank 19 to the cyclone electrowinning device 4. The hydrogen peroxide in the copper-containing waste liquid is used to participate in the electrocatalytic oxidation reaction to remove part of the organic matter in the waste liquid, and copper is electrolyzed and recovered. The electrowinning voltage is controlled according to the copper content. The electrowinning liquid circulation tank 19 is used to circulate the electrowinning residual liquid through the cyclone electrowinning device until the copper content of the electrowinning residual liquid is finally controlled to be less than 300 mg / L. The residual liquid from the electrolysis is transferred to the electrocatalytic oxidation tank 5 for further electrocatalytic oxidation. After the organic matter is removed, the centrifugal pump 6 is pumped to the first filter press 7 to filter out impurities. The sludge impurities are outsourced for treatment. The filtrate is temporarily stored in the filtrate storage tank 8 and then transferred to the neutralization reactor 10 through the centrifugal pump 9. Iron oxide or iron hydroxide is added to neutralize the sulfuric acid in the residual liquid from the electrolysis. After the pH is adjusted to 1-2, it is pumped to the fluidized displacement tower 12 with a mortar pump 11. At the same time, iron powder is gradually added from the top of the tower to countercurrently fluidize and replace the copper remaining in the solution. After deep replacement, the solution is temporarily stored in the replacement liquid overflow storage tank 13, and the mortar pump 14 is used to pump to the second filter press 16 to filter the residual iron powder in the solution. The filtrate is the refined ferrous sulfate solution, which is temporarily stored in the refined ferrous sulfate solution storage tank 17, and the mortar pump 18 is pumped to the transport tank as a raw material for producing ferrous sulfate or polyferrous sulfate. After the replacement, the copper powder is precipitated and enriched at the bottom of the tower, and is pumped to the second filter press 16 by a mortar pump 15 to obtain the copper powder.

[0063] like Figure 5 As shown, a method for comprehensive recovery and utilization of copper-containing waste liquid, the method adopts the above-mentioned device for comprehensive recovery and utilization of copper-containing waste liquid, and the method comprises:

[0064] S1, the waste liquid is transferred from the copper-containing waste liquid storage tank to the cyclone electrowinning device after passing through the filter to obtain cathode copper;

[0065] S2, using electrocatalytic oxidation reaction to remove some organic matter in the waste liquid, and electrolyze to recover copper, and control the electrolytic voltage according to the copper content;

[0066] S3, the residual liquid from the electrolysis is transferred to the electrocatalytic oxidation tank for further electrocatalytic oxidation, and after the organic matter is removed, the impurities are filtered out through the first filter press and transferred to the neutralization reactor;

[0067] S4, adding a neutralizing agent to neutralize the electrodeposition residual solution, adjusting the pH and transferring to a fluidized displacement tower, and adding iron powder to fluidize and replace the residual copper in the solution;

[0068] S5, the second filter press filters the residual iron powder in the solution, and the copper powder settles and enriches at the bottom of the fluidized bed displacement tower after displacement, and is filtered through the second filter press to obtain the copper powder;

[0069] S6. The filtrate is the refined ferrous sulfate liquid, which is temporarily stored in a ferrous sulfate storage tank as a raw material for producing ferrous sulfate or polymerized ferrous sulfate.

[0070] In one embodiment, the residual liquid from the electrolysis is added to an electrocatalytic oxidation tank, and direct current is passed through the tank, with the voltage controlled at 3V-10V. After the hydrogen peroxide in the copper-containing waste liquid is fully utilized, a small amount of hydrogen peroxide is gradually added to participate in the reaction, and organic matter is effectively degraded by electrocatalytic oxidation.

[0071] In one embodiment, the cyclone electrowinning device utilizes hydrogen peroxide in the waste liquid to electrocatalytically oxidize and remove part of the organic matter.

[0072] In one embodiment, the cyclonic electrowinning voltage is controlled at 1.8V-2.5V, and the electrowinning endpoint is that the copper content of the copper-containing waste liquid is ≤300mg / L.

[0073] In one embodiment, a neutralizing agent is added to the residual solution of electrolysis, wherein the neutralizing agent is one of iron oxide / iron hydroxide, and the neutralization end point is pH=1-2.

[0074] In one embodiment, deep copper removal adopts a fluidized displacement copper removal process. In order to ensure product quality, the displacement agent is iron powder, and the mesh size of the iron powder is required to be no less than 200 meshes.

[0075] In one embodiment, the fluidized displacement copper removal process adopts countercurrent displacement to achieve deep removal of copper and other heavy metals. The iron powder and the copper-containing waste liquid are continuously fed and discharged. The feeding speed ratio of the iron powder and the copper-containing waste liquid is 0.29kg-0.35kg iron powder: 1L copper-containing waste liquid.

[0076] Through cyclone electrolysis, hydrogen peroxide in the waste liquid is first used to catalytically oxidize part of the organic matter, and then the cathode copper is recovered by controlled voltage electrolysis. After further electrocatalytic oxidation to effectively remove the organic matter, an iron source is added to neutralize the sulfuric acid in the waste liquid, and the copper in the electrolytic residual liquid is deeply replaced by the countercurrent fluidized displacement method to obtain a refined ferrous sulfate liquid as a raw material for ferrous sulfate products or polyferric sulfate.

[0077] The waste liquid is transferred from the copper-containing waste liquid storage tank 1 through a centrifugal pump 2 and a bag filter 3 to a cyclone electrolysis device 4. The hydrogen peroxide in the copper-containing waste liquid is used to participate in an electrocatalytic oxidation reaction to remove part of the organic matter in the waste liquid, and copper is recovered by electrolysis. The electrolysis voltage is controlled according to the copper content, and the copper content of the electrolysis residual liquid is finally controlled to be less than 300 mg / L. The residual liquid of the electrolytic deposition is transferred to the electrocatalytic oxidation tank 5 for further electrocatalytic oxidation. After the organic matter is removed, the centrifugal pump 6 is pumped to the first filter press 7 to filter out impurities. The sludge impurities are outsourced for treatment. The filtrate is temporarily stored in the filtrate storage tank 8 and then transferred to the neutralization reactor 10 by the centrifugal pump 9. Iron oxide or iron hydroxide is added to neutralize the sulfuric acid in the residual liquid of the electrolytic deposition. After the pH is adjusted to 1-2, it is pumped to the fluidized displacement tower 12 by the mortar pump 11. At the same time, iron powder is gradually added from the top of the tower to countercurrent fluidize the residual copper in the displacement solution. After deep displacement, the solution is temporarily stored in the displacement liquid overflow storage tank 13, and the mortar pump 14 is used to pump to the second filter press 16 to filter the residual iron powder in the solution. The filtrate is the refined ferrous sulfate solution, which is temporarily stored in the refined ferrous sulfate solution storage tank 17, and the mortar pump 18 is pumped to the transport tank as a raw material for producing ferrous sulfate or polyferrous sulfate. After the displacement, the copper powder is precipitated and enriched at the bottom of the tower, and is pumped to the filter press 16 by the mortar pump 15 to obtain the copper powder.

[0078] The above-mentioned method for comprehensive recycling of copper-containing waste liquid realizes the comprehensive recycling of copper-containing waste liquid through cyclone electrolysis technology, electrocatalytic oxidation, and countercurrent fluidized displacement method. Using cyclone electrolysis technology, hydrogen peroxide in the micro-etching liquid is used to participate in electrocatalytic oxidation, and copper in the waste liquid is recovered after removing some organic matter. The current efficiency and copper selectivity are improved, and the quality of the obtained cathode copper is improved; the electrocatalytic oxidation method is selected to effectively and thoroughly degrade and remove organic matter in the waste liquid without causing other impurities, thereby improving the purity of the waste liquid; the acidity of the residual liquid after electrolysis is then neutralized by iron oxide and iron hydroxide to adjust the pH to 1-2 by using the countercurrent fluidized displacement process. The contact and reaction between the iron powder and the waste liquid in the countercurrent process are more sufficient, and the reaction potential of the iron powder replacing copper at the final discharge of the waste liquid is greatly improved, achieving the effect of deep replacement. In addition, the method is environmentally friendly, the same system materials are used during the treatment process, no impurities are introduced, the product quality is high, and the treatment cost is greatly reduced, so the method is suitable for large-scale production.

[0079] Compared with the prior art, the technical effects of the present invention are:

[0080] 1. Realize comprehensive recycling and utilization. No other impurity ions are introduced in the copper electrowinning recovery, acid neutralization, and copper deep replacement processes. The obtained ferrous sulfate is of high quality, realizing the resource recovery of copper and waste sulfuric acid.

[0081] 2. High copper recovery efficiency, copper in waste liquid is deeply recovered. The technology of the present invention uses cyclone electrowinning to recover cathode copper, which has higher selectivity for metallic copper than traditional electrowinning, and can maintain higher current efficiency at lower copper concentrations; on the basis of recovering most of the cathode copper, iron sources are added step by step, and iron oxide / iron hydroxide is used instead of iron powder as the iron source to neutralize most of the free sulfuric acid, which greatly reduces the cost and is more conducive to improving the efficiency of subsequent iron powder replacement of copper; and then the iron powder fluidized replacement technology is used to replace the residual metallic copper, which solves the problem of incomplete traditional replacement, and the copper is deeply recovered.

[0082] 3. The process does not introduce new impurities, and the product quality is high. The cathode copper obtained by cyclonic electrowinning is of higher quality than that of traditional electrowinning; on the basis of removing organic matter and other impurities in the waste liquid by electrocatalytic oxidation, the quality of waste sulfuric acid in the solution is greatly improved; and then after deep replacement and impurity removal, high-quality ferrous sulfate refined liquid is obtained.

[0083] 4. Realize waste treatment with waste, make full use of the residual hydrogen peroxide in the micro-etching solution to participate in electrocatalytic oxidation to remove organic matter, realize comprehensive utilization, and greatly reduce production costs.

[0084] 5. Environmentally friendly and easy to promote. Cyclone electrowinning does not have environmental problems such as low efficiency and energy consumption, acid mist and waste gas, and is easy to promote.

[0085] The following is further described in detail in conjunction with the preferred embodiments.

[0086] Example 1

[0087] Using hydrogen peroxide system micro-etching waste liquid as raw material, a cyclone electrowinning device was used to first use the hydrogen peroxide component in the micro-etching liquid to electrocatalytically oxidize and remove part of the organic matter, and then the voltage was controlled to cyclone copper electrowinning, and most of the copper was recovered as cathode copper. The content of the main components (g / t) is shown in Table 2; after further electrocatalytic oxidation, COD was effectively removed; as can be seen from Table 1, after the fluidized displacement process, copper was deeply replaced, and ferrous sulfate refined liquid was obtained after filtration and impurity removal.

[0088] The specific steps are as follows:

[0089] The micro-etching waste liquid 5m 3The product was pumped into the cyclone electrowinning device. The voltage was initially controlled at 2.5V. The product was powered on for 30 minutes for catalytic oxidation. After the hydrogen peroxide was consumed, the voltage was adjusted to 2V. The cathode copper was recovered by cyclone electrowinning. After 6 hours, when the copper content in the waste liquid was greatly reduced, high-quality cathode copper was obtained by disassembling it from the cathode. The residual liquid was transferred to the electrocatalytic oxidation device. Direct current was passed and the voltage was controlled to 5V. During the power-on process, a certain amount of hydrogen peroxide was slowly added to ensure that the concentration of hydrogen peroxide was above 100ppm. After the COD was effectively decomposed, the reaction was stopped. After filtering and removing impurities, the product was transferred to the neutralization reactor by pump, and iron oxide was added to adjust the pH to 1-2. The solution was then pumped to the displacement tower, and 200-mesh iron powder was added for fluidized displacement. The iron powder feeding rate was 0.29kg / h. For copper-containing waste liquid, the feeding rate was 1m 3 / h, and the waste liquid obtained after fluidized bed replacement is filtered to obtain ferrous sulfate refined liquid (its main components are shown in Table 1).

[0090] Table 1 Experimental test results g / L

[0091]

[0092]

[0093] Table 2 Cathode copper test results

[0094]

[0095] Example 2

[0096] Using low-concentration copper-containing waste liquid from pickling and micro-etching liquid as raw materials, a cyclone electrowinning device was used to first use the hydrogen peroxide component in the micro-etching liquid to electrocatalytically oxidize and remove part of the organic matter, and then the voltage was controlled to cyclone electrowinning copper. Most of the copper was recovered as cathode copper, and the content of the main components (g / t) is shown in Table 4; after further electrocatalytic oxidation, COD was effectively removed; as can be seen from Table 3, after the fluidized displacement process, copper was deeply replaced, and ferrous sulfate refined liquid was obtained after filtration and impurity removal.

[0097] The specific steps are as follows:

[0098] The micro-etching waste liquid 5m 3The product was pumped into the cyclone electrowinning device. The voltage was initially controlled at 2.3V. The product was powered on for 40 minutes for catalytic oxidation. After the hydrogen peroxide was consumed, the voltage was adjusted to 1.8V. The cathode copper was recovered by cyclone electrowinning. After 7 hours, when the copper content in the waste liquid was greatly reduced, high-quality cathode copper was obtained by disassembling it from the cathode. The residual liquid was transferred to the electrocatalytic oxidation device. Direct current was passed and the voltage was controlled to 10V. During the power-on process, a certain amount of hydrogen peroxide was slowly added to ensure that the concentration of hydrogen peroxide was above 50ppm. After the COD was effectively decomposed, the reaction was stopped. After filtering and removing impurities, the product was transferred to the neutralization reactor by pump, and iron oxide was added to adjust the pH to 1-2. The solution was then pumped to the displacement tower, and 300-mesh iron powder was added for fluidized displacement. The iron powder feeding rate was 0.35kg / h. For copper-containing waste liquid, the feeding rate was 1m 3 / h, the waste liquid obtained after fluidized bed replacement is filtered to obtain ferrous sulfate refined liquid (its main components are shown in Table 3).

[0099] Table 3 Experimental test results g / L

[0100]

[0101]

[0102] Table 4 Cathode copper detection results

[0103]

[0104] Example 3

[0105] Using low-concentration copper-containing waste liquid from pickling as raw material, a cyclone electrowinning device was used, followed by voltage-controlled cyclone electrowinning of copper. Most of the copper was recovered as cathode copper, and the content of the main components (g / t) is shown in Table 6. After further electrocatalytic oxidation, COD was effectively removed. As can be seen from Table 5, after the fluidized bed displacement process, copper was deeply replaced, and ferrous sulfate refined liquid was obtained after filtration and impurity removal.

[0106] The specific steps are as follows:

[0107] The pickling copper waste liquid 5m 3The product was pumped into the cyclone electrowinning device. The voltage was initially controlled at 2.3V. The product was powered on for 40 minutes for catalytic oxidation. After the hydrogen peroxide was consumed, the voltage was adjusted to 2.5V. The cathode copper was recovered by cyclone electrowinning. After 5 hours, when the copper content in the waste liquid was greatly reduced, high-quality cathode copper was obtained by disassembling it from the cathode. The residual liquid was transferred to the electrocatalytic oxidation device. Direct current was passed and the voltage was controlled to 3V. During the power-on process, a certain amount of hydrogen peroxide was slowly added to ensure that the concentration of hydrogen peroxide was above 150ppm. After the COD was effectively decomposed, the reaction was stopped. After filtering and removing impurities, the product was transferred to the neutralization reactor by pump, and iron hydroxide was added to adjust the pH to 1-2. The solution was then pumped to the displacement tower, and 400-mesh iron powder was added for fluidized displacement. The iron powder feeding rate was 0.32kg / h. For iron powder and copper-containing waste liquid, the feeding rate was 1m 3 / h, the waste liquid obtained after fluidized bed replacement is filtered to obtain ferrous sulfate refined liquid (its main components are shown in Table 5).

[0108] Table 5 Experimental test results g / L

[0109]

[0110]

[0111] Table 6 Cathode copper detection results

[0112]

[0113] Unless otherwise defined, the technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art in the technical field of the present invention. The terms used herein are only for describing specific implementation purposes and are not intended to limit the present invention. Terms such as "setting" and the like appearing in this article can indicate that one component is directly attached to another component, or that one component is attached to another component through an intermediate. Features described in this article in one embodiment may be applied to another embodiment alone or in combination with other features, unless the feature is not applicable in the other embodiment or otherwise specified.

[0114] The present invention has been described by the above embodiments, but it should be understood that the above embodiments are only for the purpose of example and description, and are not intended to limit the present invention to the scope of the described embodiments. In addition, it can be understood by those skilled in the art that the present invention is not limited to the above embodiments, and more variations and modifications can be made according to the teachings of the present invention, and these variations and modifications all fall within the scope of the protection claimed by the present invention. The protection scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A device for comprehensive recovery and utilization of copper-containing waste liquid, characterized in that: include: The copper-containing waste liquid storage tank, filter, cyclone electrowinning device, electrocatalytic oxidation tank, first filter press, neutralization reactor, fluidized bed displacement tower, second filter press, and ferrous sulfate storage tank are connected in sequence, wherein: The copper-containing waste liquid storage tank is used to collect copper-containing waste liquid. The filter is used to filter impurities. The cyclone electrowinning device is used to control the electrowinning voltage according to the copper content to obtain the electrowinning residual solution. The electrocatalytic oxidation tank is used for electrocatalytically oxidizing the electrodeposited residual liquid to remove some organic matter in the waste liquid. The first filter press is used to further filter impurities. The neutralization reactor is used to neutralize the residual liquid of the electrodeposition by adding a neutralizing agent to adjust the pH value. The fluidized displacement tower is used to fluidize and displace the residual copper in the solution of the electrolytic residual solution with adjusted pH value by adding iron powder. The second filter press is used to filter the residual iron powder and the displaced copper powder in the solution. The ferrous sulfate storage tank is used to store the filtered solution, namely the refined ferrous sulfate solution.

2. The device for comprehensive recovery and utilization of copper-containing waste liquid according to claim 1, characterized in that: It also includes a replacement liquid overflow storage tank, which is connected between the fluidized displacement tower and the second filter press and is used to temporarily store the solution overflowing from the upper part of the fluidized displacement tower.

3. The device for comprehensive recovery and utilization of copper-containing waste liquid according to claim 2, characterized in that: It also includes an electrolytic solution circulation tank, which is connected between the filter and the cyclone electrolytic device and is used to circulate the electrolytic residual liquid through the cyclone electrolytic device to obtain the electrolytic residual liquid with a copper content of less than 300 mg / L.

4. The device for comprehensive recovery and utilization of copper-containing waste liquid according to claim 3, characterized in that: It also includes a filtrate storage tank, which is connected between the first filter press and the neutralization reactor and is used to temporarily store the electrodeposition residual liquid.

5. The device for comprehensive recovery and utilization of copper-containing waste liquid according to claim 1, characterized in that: The neutralizing agent is one of ferric oxide and ferric hydroxide, and the neutralization end point is pH=1-2.

6. The device for comprehensive recovery and utilization of copper-containing waste liquid according to claim 1, characterized in that: The iron powder has a mesh size of not less than 200 meshes.

7. A method for comprehensive recycling of copper-containing waste liquid, characterized in that: The method adopts the copper-containing waste liquid comprehensive recovery and utilization device according to any one of claims 1 to 6, and the method comprises: S1, the waste liquid is transferred from the copper-containing waste liquid storage tank to the cyclone electrowinning device after passing through the filter to obtain cathode copper; S2, using electrocatalytic oxidation reaction to remove some organic matter in the waste liquid, and electrolyze to recover copper, and control the electrolytic voltage according to the copper content; S3, the residual liquid from the electrolysis is transferred to the electrocatalytic oxidation tank for further electrocatalytic oxidation, and after the organic matter is removed, the impurities are filtered out through the first filter press and transferred to the neutralization reactor; S4, adding a neutralizing agent to neutralize the electrodeposition residual solution, adjusting the pH and transferring to a fluidized displacement tower, and adding iron powder to fluidize and replace the residual copper in the solution; S5, the second filter press filters the residual iron powder in the solution, and the copper powder settles and enriches at the bottom of the fluidized bed displacement tower after displacement, and is filtered through the second filter press to obtain the copper powder; S6. The filtrate is the refined ferrous sulfate liquid, which is temporarily stored in a ferrous sulfate storage tank as a raw material for producing ferrous sulfate or polymerized ferrous sulfate.

8. The method for comprehensive recovery and utilization of copper-containing waste liquid according to claim 7, characterized in that: Direct current is passed through the electrocatalytic oxidation tank, and the voltage is controlled at 3V-10V. After the hydrogen peroxide in the copper-containing waste liquid is fully utilized, a small amount of hydrogen peroxide is gradually added to participate in the reaction, and organic matter is effectively degraded through electrocatalytic oxidation.

9. The method for comprehensive recovery and utilization of copper-containing waste liquid according to claim 7, characterized in that: The voltage of the cyclone electrowinning device is controlled at 1.8V-2.5V, and the electrowinning end point is that the copper content of the copper-containing waste liquid is ≤300mg / L.

10. The method for comprehensive recovery and utilization of copper-containing waste liquid according to claim 7, characterized in that: The fluidized displacement tower adopts countercurrent displacement, wherein the iron powder and the copper-containing waste liquid are continuously fed and discharged, and the feeding speed ratio of the iron powder and the copper-containing waste liquid is 0.29kg-0.35kg iron powder: 1L copper-containing waste liquid.

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