A device for electrolytic recovery of spent tungsten alloys

Abstract

The present application relates to tungsten resource recovery and wet electro-metallurgical technology field, specifically discloses a kind of waste tungsten alloy electrolytic recovery device.The device includes graphite crucible as electrolytic cell and cathode, center suspension type anode assembly is arranged in crucible, and the effective working area of anode is limited by insulating sleeve;Crucible lower part is provided with conical settling zone and detachable anode mud collection assembly, and the disturbance of electrolyte circulation to the sediment is reduced by slow flow isolation assembly.The device is equipped with upper circulating filtration system, ammonia-containing tail gas condensation reflux assembly and external cooling jacket.The present application realizes the effective separation of anode mud and electrolytic reaction zone, reduces the loss of ammonia volatilization, ensures the uniformity and stability of current density and temperature, significantly improves the efficiency and maintenance convenience of waste tungsten alloy electrolytic recovery.

Description

Technical Field

[0001] This invention relates to the field of tungsten resource recovery and hydrometallurgical technology, specifically to an electrolytic recovery device for waste tungsten alloys. The device uses a graphite crucible as both an electrolytic cell and a cathode, and has functions such as anode working area control, anode mud sedimentation and separation, ammonia-containing tail gas condensation and reflux, electrolyte circulation filtration, and temperature regulation. Background Technology

[0002] Tungsten and its alloys possess high melting points, density, hardness, wear resistance, and high-temperature stability, making them widely used in machining, mining tools, wear-resistant components, high-density counterweights, and other industrial fields. With the continuous use of tungsten-containing products during production, processing, and service, various secondary tungsten resources are generated, including scrap cutting tools, scrap bars, scrap blocks, scrap offcuts, and grinding media. These wastes typically still contain a high proportion of tungsten and may also contain valuable metals such as cobalt, nickel, iron, and copper. Classifying, recycling, and utilizing these materials can improve the utilization rate of secondary tungsten resources and reduce resource waste and environmental burden caused by waste stockpiling.

[0003] The term "scrap tungsten alloy" as used in this specification mainly includes scrap tungsten carbide-based cemented carbide and scrap tungsten-based high-density alloy. Scrap tungsten carbide-based cemented carbide typically uses tungsten carbide as the main hard phase, with cobalt, nickel, iron, or their alloys as the metallic binder phase. It may also contain other refractory metal carbides such as titanium carbide, tantalum carbide, and niobium carbide, depending on product performance requirements. Common scrap materials include scrap cutting tools, scrap mining teeth, scrap wear-resistant parts, scrap cemented carbide round bars, scrap molds, production offcuts, and tungsten-containing materials generated during the grinding process.

[0004] Waste tungsten-based high-density alloys typically use metallic tungsten particles as the main phase, with nickel-iron, nickel-copper, or alloys containing nickel, iron, copper, cobalt, or other metals as the matrix or binder phase. Typical materials include W-Ni-Fe and W-Ni-Cu alloys. Tungsten-based high-density alloys can be used for counterweights, shielding components, and other parts requiring high density and high mechanical strength. Compared to tungsten carbide-based cemented carbides, these alloys differ in the form of tungsten, matrix phase composition, microstructure, and anodic dissolution behavior. However, during electrolysis, the main migration direction of tungsten is oxidation to soluble tungsten-containing components.

[0005] Existing methods for recycling waste tungsten alloys mainly include mechanical crushing, zinc melting, high-temperature oxidation-reduction, acid leaching, alkaline treatment, and electrochemical dissolution. For waste tungsten carbide-based cemented carbide, mechanical crushing and some direct regeneration methods typically have high requirements for the grade, composition, cleanliness, and impurity content of the waste material; zinc melting requires melting, infiltration, and subsequent zinc removal, requiring high process control; high-temperature oxidation-reduction involves high reaction temperatures and consumes a lot of energy; acid leaching or alkaline treatment usually requires solid-liquid separation, solution purification, and conversion of tungsten-containing intermediate products. For waste cemented carbide with complex compositions, surface coatings, or different binder phases, the above processes may also have problems such as long process flow, high reagent consumption, difficulty in impurity control, or fluctuations in the quality of recycled products. For waste tungsten-based high-density alloys, because metallic tungsten forms a tight bond with matrix components such as nickel, iron, and copper, conventional acid, alkali, or solvent treatment may also have problems such as slow reaction rates, high reagent consumption, long process flow, and difficulty in separating multiple metal components.

[0006] Electrochemical dissolution is an important method in the recycling of waste cemented carbide. This method typically uses the waste cemented carbide as the anode, connects a DC power supply to an electrolyte, and adjusts the electrolyte composition, cell voltage, current density, temperature, and electrolysis time to cause one or more components in the anode to oxidize and dissolve or disintegrate. Compared to some high-temperature treatment methods, aqueous electrochemical treatment can generally operate under relatively mild temperature conditions, and the electrolysis process can be controlled by adjusting parameters such as electrolyte composition, current density, voltage, temperature, and circulation status.

[0007] Although existing electrolytic recovery technologies can achieve selective dissolution of anodes, there are still areas for improvement when dealing with miniaturized and centralized processing of anodes from different sources and types: (1) The adaptability of anode installation, immersion position and effective exposure area lack stable control, and the actual current density and electrode spacing are prone to change; (2) Incompletely reacted alloy particles, insoluble impurities and anode mud generated during electrolysis are easily dispersed at the bottom of the electrolytic cell, and it is difficult to collect them without discharging a large amount of electrolyte; (3) The flow generated by electrolyte circulation may disturb the settled particles, and there is a mutual constraint between anode mud settling and electrolyte mass transfer; (4) Ammonia-containing electrolytes are prone to ammonia volatilization during electrolysis heating, circulation and gas evolution, and it is difficult to achieve ammonia recovery and utilization by using only end absorption.

[0008] Therefore, it is necessary to provide a waste tungsten alloy electrolytic recycling device suitable for different types and shapes of waste tungsten alloys, which can effectively control the anode area, achieve efficient solid-liquid separation, have tail gas recovery function, and precise temperature control. This device enables the alloy to be stably installed and form a controllable anode working area, with the electrolytic reaction area and the anode mud settling and collection area relatively separated. While maintaining electrolyte circulation and temperature uniformity, it reduces bottom particle backmixing and can collect electrolytic products. It can also condense and reflux the ammonia-containing tail gas generated during the electrolysis process and absorb it at the end, thereby improving the stability of the electrolysis process, the convenience of product collection, and the recyclability of the ammonia-containing electrolyte. Summary of the Invention

[0009] This invention addresses the problems in existing waste tungsten alloy electrolytic recycling processes, such as difficulty in maintaining a constant anode area, easy suspension and blockage of anode mud, severe ammonia volatilization, uneven temperature control, and inconvenient slag removal. It provides a waste tungsten alloy electrolytic recycling device with optimized structure, stable operation, and high recycling efficiency.

[0010] This invention uses waste tungsten alloy as the anode and a graphite crucible as both the electrolytic cell and cathode. A centrally suspended alloy anode is positioned within the graphite crucible, and insulating components define the anode's working area, creating a relatively uniform electrode spacing and current distribution between the anode and the cylindrical cathode. Tungsten in the waste tungsten alloy undergoes an anodic electrochemical reaction in an ammonia-ammonium chloride electrolyte, primarily entering the electrolyte as soluble tungsten-containing components. Simultaneously, metal ions capable of cathodic reduction are deposited and recovered through the graphite cathode, and a conical settling zone is incorporated at the bottom of the graphite crucible to slow the flow. The system includes an isolation assembly and a detachable anode mud collection assembly for the centralized collection of incompletely reacted waste tungsten alloy particles, insoluble impurities, and anode mud. An upper electrolyte circulation pipeline allows the electrolyte to circulate within the electrolysis reaction zone, reducing disturbance to the lower settling zone. An ammonia-containing tail gas condensation and condensate return assembly ensures that some of the ammonia and water vapor volatilized during electrolysis is condensed and returned to the electrolysis chamber, while uncondensed gas is sent to the tail gas absorption assembly. A cooling jacket and detection elements monitor and regulate the electrolysis temperature and electrolyte state.

[0011] Therefore, this invention can improve the integration of anode mud collection, separation of tungsten-containing particles from cathode recyclables, electrolyte recycling, and ammonia-containing tail gas treatment in the electrolysis of waste tungsten alloys, and improve the stability of the electrolysis process and the convenience of equipment maintenance.

[0012] To achieve the above objectives, the present invention adopts the following technical solution:

[0013] An electrolytic recycling device for waste tungsten alloy includes a graphite crucible, an insulating cover, an anode assembly, and an insulating assembly.

[0014] The graphite crucible has an inner cavity that forms an electrolytic cell, serving not only as a container for the electrolyte but also as an electrolytic cathode. It is electrically connected to the negative terminal of a DC power supply, which simplifies the equipment structure and improves space utilization.

[0015] The insulating cover is detachably sealed at the top opening of the graphite crucible. The insulating cover is provided with an anode positioning hole, a liquid filling port and a tail gas outlet, realizing an integrated layout of liquid inlet, exhaust and electrode introduction.

[0016] The insulating cover is made of polytetrafluoroethylene, polyvinylidene fluoride, polypropylene, corrosion-resistant engineering plastics, or other corrosion-resistant insulating materials. A sealing assembly is provided between the insulating cover and the graphite crucible, and the sealing assembly includes a sealing ring, a sealing gasket, a compression ring, or a snap-fit ​​structure.

[0017] The anode assembly is inserted through the anode positioning hole and arranged along the central axis of the graphite crucible to ensure the uniformity of the electric field distribution; the anode assembly includes a waste alloy anode and a conductive clamp, and the conductive clamp is electrically connected to the positive terminal of the DC power supply.

[0018] Specifically, the anode assembly is equipped with an insulating component to isolate the non-working area of ​​the waste tungsten alloy anode. This is achieved by an insulating sleeve fitted over the outside of the waste alloy anode. This insulating sleeve can not only move and be fixed along the axial direction of the waste alloy anode to flexibly adjust the exposed length and area of ​​the anode's working section, ensuring a constant current density during electrolysis, thereby reducing the impact of differences in the shape and size of different batches of raw materials on the actual current density of the anode and maintaining a relatively stable effective electrolysis area for the waste tungsten alloy anode during electrolysis; simultaneously, in conjunction with the axial positioning mechanism, the installation height of the waste alloy anode within the graphite crucible can be precisely adjusted and locked to adapt to different liquid levels and reaction stages.

[0019] Furthermore, the graphite crucible has a conical settling zone at its lower part, and an anode mud collection assembly is detachably connected to the bottom of the conical settling zone. The anode mud collection assembly is a collection basket detachably installed at the bottom of the conical settling zone; the bottom of the conical settling zone has a detachable plug (including a support, positioning step, or limiting groove for installing the anode mud collection assembly, etc.). The collection basket can be removed by opening the detachable plug, realizing online cleaning of the anode mud without draining the electrolyte.

[0020] To further optimize solid-liquid separation, the device also includes a slow-flow isolation component. This component is located inside the graphite crucible, below the anode working section and above the conical settling zone. It divides the inner cavity of the graphite crucible into an upper circulating electrolysis zone and a lower static settling zone. The middle section of the component has a particle channel corresponding to the central axis of the waste alloy anode, allowing anode mud to pass through. This allows particles detached from the anode working section to enter the conical settling zone under gravity. Furthermore, a liquid flow gap or several slow-flow holes are provided between the component's edge and the inner wall of the graphite crucible to ensure limited liquid exchange between the circulating electrolysis zone and the static settling zone. This reduces the direct impact of the circulating liquid on the settled particles, effectively blocking the disturbance of the upper circulating flow to the lower sedimentation zone, ensuring efficient anode mud settling.

[0021] Furthermore, the device also includes a high-efficiency electrolyte circulation pipeline, which includes an outlet, a circulation pump, a filter, and a return outlet. Both the outlet and return outlet are located on the sidewall of the graphite crucible and above the slow-flow isolation component, ensuring that the electrolyte primarily flows within the circulating electrolysis zone and maintaining a relatively low liquid flow velocity in the static settling zone below the slow-flow isolation component. To prevent fine particles from being drawn into the circulation system from the settling zone, an anti-particle-intake component is provided at the outlet, selected from a filter screen, filter cover, porous baffle, or cyclone separator. Simultaneously, the return outlet is oriented towards or along the circumferential direction of the graphite crucible's inner wall, allowing the returning electrolyte to flow slowly along the inner wall of the graphite crucible, avoiding direct impact on the hard alloy anode and the conical settling zone. The circulating pump is an ammonia-resistant, chloride-ion-resistant, and corrosion-resistant circulating pump. The flow-through components of the circulating pump are made of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), engineering plastics, graphite, or other corrosion-resistant materials. The filter has a detachable structure and contains filter elements, filter screens, or filter bags for easy cleaning and maintenance.

[0022] To address the issue of ammonia gas escape during electrolysis, the device is equipped with a tail gas condensation and reflux assembly. This assembly includes a condenser, a condensate reflux channel, and an uncondensed gas discharge channel. The inlet of the condenser is connected to the tail gas outlet; the volatilized ammonia gas is condensed into a liquid phase and flows back to the electrolysis chamber of the graphite crucible through the condensate reflux channel, achieving material recovery. The other end of the uncondensed gas discharge channel is connected to a tail gas absorption assembly, which includes at least one tail gas absorption bottle filled with an absorbent liquid capable of absorbing ammonia gas for final environmental treatment, effectively reducing material loss and environmental pollution.

[0023] To ensure the stability of the electrolytic reaction, the graphite crucible is covered with a cooling jacket. The cooling jacket and the outer wall of the graphite crucible form a cooling medium flow cavity. The cooling jacket has a cooling water inlet at the bottom and a cooling water outlet at the top. To prevent short circuits, the cooling jacket is made of electrically insulating material, or is electrically isolated from the graphite crucible by an electrically insulating layer.

[0024] In addition, the insulating cover is provided with multiple mounting holes for detection elements, into which temperature sensors, pH sensors / conductivity sensors are inserted. The probes of each sensor extend into the electrolyte to achieve real-time monitoring of reaction parameters. The conductive clamp is located above the insulating cover and is provided with an insulating protective part covering the non-clamping area; an insulating positioning sleeve is provided in the anode positioning hole to keep the anode assembly electrically insulated from the insulating cover and the graphite crucible, ensuring the safe operation of the equipment.

[0025] The present invention also discloses a method of using the device, comprising the following steps:

[0026] When using, add the ammonia-ammonium chloride electrolyte into the electrolytic cell of the graphite crucible, and make sure the electrolyte level is below the insulating cover.

[0027] The waste tungsten alloy to be processed is fixed on the conductive clamp of the anode assembly. The exposed area of ​​the alloy anode is limited by the insulating component. The installation height of the alloy anode is adjusted by the axial positioning mechanism so that the working section of the anode is immersed in the electrolyte and the alloy anode is located in the central area of ​​the graphite crucible.

[0028] The alloy anode is connected to the positive terminal of a DC power supply, and the graphite crucible is connected to the negative terminal of a DC power supply. After energization, the metallic binder phase in the alloy undergoes electrochemical oxidation and dissolution at the anode. Some unreacted particles and other insoluble impurities gradually detach from the anode surface, forming anode sludge which enters the settling and collection area. The main recovery pathway for tungsten is to enter the electrolyte and form soluble tungsten-containing components.

[0029] Particles detached from the anode move downwards under gravity and enter the conical settling zone through the particle channel on the slow-flow isolation component. Since the conical settling zone is located below the circulating electrolysis zone, and the outlet and return ports of the circulating pipeline are both located above the slow-flow isolation component, the liquid flow velocity in the conical settling zone is lower than that in the circulating electrolysis zone, which is conducive to the settling and concentration of solid particles.

[0030] Settled particles enter and are retained by the anode mud collection assembly. After electrolysis, the anode mud collection assembly can be removed from the conical settling zone for cleaning, drying, and further processing of the tungsten-containing particles and anode mud.

[0031] During electrolysis, a circulating pump draws the electrolyte from the circulating electrolysis zone through the outlet. After being filtered, the electrolyte returns to the graphite crucible through the return outlet. Because the return outlet is arranged tangentially or circumferentially along the inner wall of the graphite crucible, the returning electrolyte flows along the inner wall of the graphite crucible, thereby reducing the direct impact on the anode surface and the conical settling zone.

[0032] During electrolysis, the ammonia-containing tail gas enters the condenser through the tail gas outlet on the insulating cover. In the condenser, the ammonia-containing tail gas exchanges heat with the cooling medium, and some of the ammonia and water vapor condenses to form ammonia-containing condensate. The ammonia-containing condensate returns to the electrolysis chamber through the condensate return channel, while the uncondensed gas enters the tail gas absorption assembly through the anti-backflow buffer bottle.

[0033] The cooling water in the cooling jacket absorbs the heat generated by the graphite crucible and electrolyte to prevent excessive rise in electrolyte temperature. Temperature, pH, conductivity, and level sensors are used to monitor the electrolyte's operating status, and the controller can adjust the cooling water flow rate, circulation flow rate, or replenishment volume.

[0034] Advantages and beneficial effects of the present invention:

[0035] 1. Precise and controllable current density: Through the cooperation of the insulating sleeve and the axial positioning mechanism, the dynamic adjustment and locking of the anode working area is realized, which overcomes the current fluctuation caused by irregular anode consumption in traditional methods and ensures the high efficiency and stability of the electrolysis process.

[0036] 2. Highly efficient and thorough solid-liquid separation: The innovative design of "conical settling zone + slow flow isolation component" combined with tangential liquid return and anti-particle suction measures creates a stable static settling environment, effectively preventing secondary suspension of anode mud and significantly reducing the load on subsequent filtration equipment.

[0037] 3. Zero material waste and environmental friendliness: The tail gas condensation and reflux component can reduce electrolyte loss, stabilize the ammonia concentration of the electrolyte, and significantly recover volatile ammonia components. Combined with the end tail gas absorption, it realizes green production throughout the entire process.

[0038] 4. Precise temperature control and safe operation: The external insulating cooling jacket enables high-precision control of the electrolyte temperature; the insulation protection design of the whole system (insulating positioning sleeve, insulating protection part, etc.) eliminates the risk of short circuit.

[0039] 5. Convenient maintenance and continuous production: The design of detachable plugs and collection baskets allows for cleaning of anode sludge without stopping the machine to empty it; the detachable filter is easy to replace, which greatly improves production efficiency. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the overall structure of a waste tungsten alloy electrolytic recycling device according to the present invention;

[0041] In the diagram, 1-Anode positioning hole, 2-Conductive clamp, 3-Temperature sensor, 4-pH sensor / conductivity sensor, 5-Liquid filling port, 6-Tail gas outlet, 7-Condensate return channel, 8-Tail gas absorption assembly, 9-Scrap alloy anode, 10-Insulating sleeve, 11-Slow flow isolation assembly, 12-Graphite crucible, 13-Cooling jacket, 14-Liquid outlet, 15-Circulating pump, 16-Filter, 17-Return port, 18-Anode mud collection assembly, 19-Removable plug, 20-Cooling water inlet, 21-Cooling water outlet, 22-DC power supply. Detailed Implementation

[0042] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. The following embodiments are used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention.

[0043] like Figure 1 As shown, a waste tungsten alloy electrolytic recycling device mainly includes a graphite crucible 12, an insulating cover, an anode assembly, and related auxiliary systems.

[0044] The graphite crucible 12 serves as the electrolytic cell body, made of high-density, high-purity graphite. Its inner wall is corrosion-resistant and exhibits excellent electrical conductivity, making it suitable for direct use as the cathode. A cooling jacket 13 tightly encloses the outside of the graphite crucible 12. The cooling jacket 13 is made of insulating material (such as PVC or PP), and its interior forms a cooling medium flow chamber. The cooling jacket 13 has a cooling water inlet 20 at the bottom and a cooling water outlet 21 at the top. A constant-temperature cooling water supply is provided by an external circulating chiller, enabling precise temperature control during the electrolysis process.

[0045] The insulating cover is made of corrosion-resistant engineering plastic and is sealed to the graphite crucible 12 via a flange or snap-fit ​​structure. The insulating cover has an anode positioning hole 1, a liquid filling port 5, a tail gas outlet 6, and multiple mounting holes for detection elements. The anode positioning hole 1 is fitted with a polytetrafluoroethylene insulating sleeve to ensure insulation between the anode assembly and the cover and cathode. The liquid filling port 5 is used to replenish the electrolyte, and temperature sensors 3 and pH / conductivity sensors 4 are inserted into the mounting holes for real-time monitoring of the electrolysis status.

[0046] The anode assembly includes a scrap alloy anode 9 (such as a YG8 cemented carbide block), a conductive clamp 2, and an insulating sleeve 10. The conductive clamp 2 is made of copper or stainless steel and is externally wrapped with an insulating layer, leaving only the clamping contact surface. The scrap alloy anode 9 is suspended below the conductive clamp 2 and immersed in the electrolyte. The insulating sleeve 10 is fitted onto the upper rod of the scrap alloy anode 9 and can be moved axially to adjust its position. It is locked by fastening screws, thereby precisely controlling the exposed length of the lower anode working section and thus fixing the effective reaction area of ​​the anode.

[0047] The lower part of the inner cavity of the graphite crucible 12 is designed as a conical settling zone. A slow-flow isolation component 11 is installed below the anode working section. This component is a porous plate or a baffle with a central through-hole, with gaps between its edges and the inner wall of the crucible. The slow-flow isolation component 11 divides the inner cavity into upper and lower parts: the upper part is the circulating electrolysis zone, and the lower part is the static settling zone. Electrolytically exfoliated tungsten carbide particles settle through the central hole, while the circulating liquid flow in the upper part is confined to the upper region, reducing disturbance to the bottom sediment. A removable anode sludge collection component 18 (such as a collection basket with a filter) is installed at the bottom of the conical settling zone. By removing the removable plug 19 at the bottom, the collection basket can be pulled out to clean the anode sludge without draining the electrolyte.

[0048] The electrolyte circulation system includes an outlet 14, a circulation pump 15, a filter 16, and a return outlet 17. The outlet 14 is located on the side wall above the slow-flow isolation assembly 11 and is equipped with a filter to prevent particle suction. The circulation pump 15 draws out the supernatant, which, after passing through the filter 16 to remove minute impurities, returns through the return outlet 17. The return outlet 17 is tangentially positioned along the inner wall of the graphite crucible 12, causing the return liquid to flow down the wall in a rotating motion, forming a gentle flow that promotes heat transfer and concentration uniformity while avoiding direct impact on the bottom sediment.

[0049] The exhaust gas treatment system includes a condenser, a condensate return channel 7, and an exhaust gas absorption assembly 8. Bubbles generated during electrolysis carry ammonia gas out of the exhaust gas outlet 6 and into the condenser. After being condensed into liquid, the ammonia gas flows back into the graphite crucible 12 through the condensate return channel 7, achieving material recovery. Any uncondensed trace amounts of gas enter the exhaust gas absorption assembly 8 (such as an acid spray tower) through pipelines for harmless treatment.

[0050] During operation, the DC power supply 22 is connected. The cobalt in the waste alloy anode 9 is oxidized and dissolved, and the tungsten carbide falls off to form anode mud, which settles into the collection basket. The circulation system maintains the uniformity of electrolyte temperature and concentration, and the temperature control system maintains the set temperature. When the collection basket is full, electrolysis is stopped, the removable plug 19 is opened, the collection basket is replaced, and operation can continue.

[0051] Example 1

[0052] This embodiment describes a method for treating waste WC-Co round bars using an ammonia-ammonium chloride electrolyte in an electrolytic recycling device.

[0053] Step 1, Raw material pretreatment:

[0054] Waste WC-Co cemented carbide round bars were selected as raw materials for processing. The surface was degreased, rinsed with clean water, and then the oxides, solder and other impurities attached to the surface were mechanically removed. After drying, they were used as waste alloy anodes 9.

[0055] Step 2, Electrolyte preparation:

[0056] Prepare an ammonia-ammonium chloride mixed electrolyte in a corrosion-resistant container, adjust it to a suitable pH range, and set it aside for use.

[0057] Step 3, Anode Installation:

[0058] The pretreated carbide round bar is fixed to the conductive clamp 2, and the exposed length of the anode working section is determined by the insulating sleeve 10; the anode is immersed in the electrolyte and its position is adjusted so that it is in the central area of ​​the graphite crucible 12.

[0059] Step 4: Start the cooling and exhaust system:

[0060] Turn on the cooling water of the condenser and cooling jacket 13 to indirectly cool the electrolysis system; confirm that the condensate return channel 7 and the tail gas absorption component 8 are unobstructed, and that the system remains open to the atmosphere and does not form a closed pressure space.

[0061] Step 5, Electrolyte circulation:

[0062] Start the circulation pump 15 to drive the electrolyte circulation flow, and adjust the circulation flow rate according to the anode mud settling state; if back mixing occurs in the settling zone, the flow rate can be reduced or the intermittent circulation mode can be switched to ensure that the solid particles settle fully.

[0063] Step 6: Electrolysis with electricity:

[0064] Using a graphite crucible 12 as the cathode and a cemented carbide round rod as the anode, a DC power supply 22 is connected to carry out electrolysis in a constant current mode with phased current ramp-up. During operation, the cell voltage and electrolyte temperature are monitored. If any abnormality occurs, the current is adjusted or the power supply is suspended in time. A pulse power supply mode can also be used as needed.

[0065] Step 7: Anode mud settling and collection:

[0066] During electrolysis, the metallic bonding phase in the cemented carbide undergoes anodic dissolution, and a small amount of insoluble impurities and unreacted solid particles enter the settling zone under gravity for collection; a small amount of fine particles flowing with the electrolyte are intercepted by the circulating filter and subsequently recycled and processed.

[0067] Step 8: Exhaust gas condensation and treatment:

[0068] The ammonia-containing tail gas generated by electrolysis is passed into a condenser for cooling. The condensed ammonia-containing liquid is returned to the electrolytic cell, and the uncondensed gas is discharged after being treated by the tail gas absorption component 8.

[0069] Step 9, Electrolysis Endpoint Control:

[0070] When the anodic dissolution reaches the expected level, the concentrations of ammonium tungstate and cobalt ions in the electrolyte meet the standards, or the electrolysis parameters show continuous abnormalities, the electrolysis endpoint is determined. After reaching the endpoint, the DC power supply is cut off first, then the electrolyte circulation is stopped, and the cooling and exhaust gas systems continue to operate. The cover is opened only after the exhaust gas in the tank is completely discharged.

[0071] Step 10, Product Recovery:

[0072] Remove the remaining hard alloy anode, clean and dry it, and keep it. Collect the electrolyte and obtain ammonium tungstate product by filtration, impurity removal, concentration and crystallization. Collect the tungsten-containing anode mud in the sedimentation zone and the cathode deposited product on the inner wall of the graphite crucible 12. After cleaning, filtration and drying, they can be further processed or analyzed.

Claims

1. A waste tungsten alloy electrolytic recycling device, characterized in that, include: A graphite crucible (12) has an inner cavity that forms an electrolytic cell. The graphite crucible (12) also serves as a cathode and is electrically connected to the negative terminal of a DC power supply (22). An insulating cover is detachably provided at the upper opening of the graphite crucible (12). The insulating cover is provided with an anode positioning hole (1), a liquid filling port (5), and a tail gas outlet (6). An anode assembly is inserted through the anode positioning hole (1) and arranged along the central axis of the graphite crucible (12). The anode assembly includes a waste alloy anode (9) and a conductive clamp (2), the conductive clamp (2) being electrically connected to the positive terminal of the DC power supply (22); and an insulating assembly is disposed on the waste alloy anode (9) to isolate the non-working area of ​​the waste alloy anode (9) to limit the exposed length and area of ​​the anode working section. The graphite crucible (12) has a conical settling zone at its lower part, and the bottom of the conical settling zone is detachably connected to an anode mud collection assembly (18).

2. The waste tungsten alloy electrolytic recycling device according to claim 1, characterized in that, It also includes a slow-flow isolation component (11), which is disposed inside the graphite crucible (12) and located below the anode working section and above the conical settling zone, dividing the inner cavity into an upper circulating electrolysis zone and a lower static settling zone; The slow-flow isolation component (11) has a particle channel in the middle for the anode mud to pass through, and its edge has a liquid flow gap or several slow-flow holes between it and the inner wall of the graphite crucible (12).

3. The waste tungsten alloy electrolytic recycling device according to claim 2, characterized in that, It also includes an electrolyte circulation pipeline, which includes an outlet (14), a circulation pump (15), a filter (16), and a return outlet (17). The liquid outlet (14) and liquid return outlet (17) are both located on the side wall of the graphite crucible (12) and above the slow-flow isolation assembly (11); The liquid outlet (17) is set along the tangential or circumferential direction of the inner wall of the graphite crucible (12).

4. The waste tungsten alloy electrolytic recycling device according to claim 1, characterized in that, It also includes an exhaust gas condensation and recirculation assembly, which includes a condenser, a condensate recirculation channel (7), and an uncondensed gas discharge channel; The inlet of the condenser is connected to the outlet of the exhaust gas (6). One end of the condensate return channel (7) is connected to the condensate collection part of the condenser, and the other end is connected to the electrolysis chamber of the graphite crucible (12). The other end of the uncondensed gas discharge channel is connected to the exhaust gas absorption assembly (8).

5. The waste tungsten alloy electrolytic recycling device according to claim 1, characterized in that, The graphite crucible (12) is covered with a cooling jacket (13) on the outside. The cooling jacket (13) has a cooling water inlet (20) at the bottom and a cooling water outlet (21) at the top. The cooling jacket (13) and the outer wall of the graphite crucible (12) form a cooling medium flow cavity. The cooling jacket (13) is made of an electrically insulating material or electrically isolated from the graphite crucible (12) through an electrically insulating isolation layer.

6. The waste tungsten alloy electrolytic recycling device according to claim 1, characterized in that, The insulating component is an insulating sleeve (10), which is sleeved on the outside of the waste alloy anode (9) and can move and be fixed along the axial direction of the waste alloy anode (9) to adjust the exposed length of the anode working section. The anode assembly also includes an axial positioning mechanism for adjusting and locking the installation height of the waste alloy anode (9) within the graphite crucible (12).

7. The waste tungsten alloy electrolytic recycling device according to claim 2, characterized in that, The anode mud collection assembly (18) is a collection basket that is detachably installed at the bottom of the conical settling zone; The bottom of the conical settling zone is provided with a detachable plug (19), and the collection basket can be removed by opening the detachable plug (19).

8. The waste tungsten alloy electrolytic recycling device according to claim 1, characterized in that, The insulating cover is also provided with multiple detection element mounting holes, in which temperature sensor (3) and pH sensor / conductivity sensor (4) are inserted, and the probes of each sensor extend into the electrolyte.

9. The waste tungsten alloy electrolytic recycling device according to claim 3, characterized in that, The liquid outlet (14) is provided with a particle inhalation prevention component, which is selected from one of the following: filter screen, filter cover, porous baffle or cyclone separator. The filter (16) has a detachable structure and is equipped with a filter element, filter screen or filter bag inside.

10. The waste tungsten alloy electrolytic recycling device according to claim 1, characterized in that, The conductive clamp (2) is located above the insulating cover and is provided with an insulating protective part that covers the non-clamping area; An insulating positioning sleeve is provided inside the anode positioning hole (1) to keep the anode assembly electrically insulated from the insulating cover and the graphite crucible (12).

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