A waste circuit board processing system and method

Abstract

This invention discloses a waste circuit board processing system and method, belonging to the field of waste circuit boards. The waste circuit board processing system includes a crushing device, a dehydration device, a mixer, a microwave pyrolysis furnace, a heat exchanger, an absorption tower, an adsorption system, an incineration system, and a chimney, arranged sequentially along the processing direction. The desorption gas outlet of the adsorption system is connected to the incineration system via a pipeline, and the exhaust port of the adsorption system is connected to the chimney via a pipeline. The exhaust port of the incineration system is connected to both the chimney and the adsorption system via pipelines. This invention employs a microwave high-temperature pyrolysis + oxide absorption process to separate the circuit board metal from the substrate, effectively reducing the generation of gases such as dioxins.

Description

Technical Field

[0001] This invention belongs to the field of waste circuit boards, and particularly relates to a waste circuit board processing system and method. Background Technology

[0002] Circuit boards contain valuable metals such as gold, copper, and tin, and their matrix is ​​made of phenolic resin, epoxy resin, polyimide resin, or polytetrafluoroethylene resin, containing brominated flame retardants. Current pyrometallurgical processes used to process discarded circuit boards, such as high-temperature pyrolysis, produce pollutants including hydrogen chloride, hydrogen bromide, and dioxins, as well as acidic gases and volatile organic compounds. Direct release of these gases causes significant environmental pollution. Summary of the Invention

[0003] The purpose of this invention is to provide a waste circuit board processing system and method to overcome at least one of the above-mentioned defects in the prior art.

[0004] To achieve this objective, the present invention adopts the following technical solution:

[0005] The present invention provides a waste circuit board processing system, comprising a crushing device, a dehydration device, a mixer, a microwave pyrolysis furnace, a heat exchanger, an absorption tower, an adsorption system, an incineration system, and a chimney arranged sequentially along the processing direction. The desorption gas outlet of the adsorption system is connected to the incineration system through a pipeline, the exhaust port of the adsorption system is connected to the chimney through a pipeline, and the exhaust port of the incineration system is connected to the chimney and the adsorption system through pipelines respectively.

[0006] Preferably, the crushing device includes a mounting frame, a crushing box, a crushing roller assembly, a first motor, a transmission assembly, a crushing blade assembly, a blower, a screening assembly, a connecting plate, and a cooling assembly. The crushing box is fixed to the mounting frame. Two partitions are located at the top of the crushing box, dividing the upper space inside the crushing box into three independent spaces. Crushing roller assemblies are installed on both the left and right sides of the upper part of the crushing box, with the crushing ends of the two roller assemblies located in the left and right independent spaces respectively. A first motor is fixed to the front wall of the upper part of the crushing box, and the first motor is connected to the left and right crushing roller assemblies via the transmission assembly. A connecting plate is fixed in the middle independent space, and a crushing blade assembly and a cooling assembly are fixed on the connecting plate. The crushing ends of the crushing blade assemblies are located in the middle of the crushing box, and the cooling end of the cooling assembly faces the crushing ends of the crushing blade assemblies. A blower is fixed to the mounting frame, and the blower's outlet extends through the left side wall of the crushing box to the lower part of the crushing box. The screening assembly is located on the right side wall of the crushing box, opposite to the blower's outlet.

[0007] Preferably, the screening assembly includes a screen, a collection box, a mounting plate, and bolts. A through hole is provided on the lower right side wall of the crushing box, and a feed inlet is provided on the left side of the collection box. The feed inlet communicates with the through hole, and a screen is screwed to the feed inlet. A discharge port is provided at the bottom of the collection box, and mounting plates are fixed to the upper and lower side walls of the collection box. The mounting plates are detachably fixed to the crushing box by bolts.

[0008] Preferably, it further includes a first rotating shaft, a first bearing seat, a first cam, a connecting rod, a swing rod, a knocking block, and a spring. The first bearing seat is fixed to the front side wall of the lower part of the crushing box. One end of the first rotating shaft is connected to the transmission assembly. The other end of the first rotating shaft passes through the first bearing seat and the front side wall of the crushing box and extends into the crushing box where the first cam is fixed. A connecting rod is fixed to the inner side wall of the crushing box below the through hole. A swing rod is hinged to the left end of the connecting rod. A spring is fixed to the lower right side wall of the swing rod. The right end of the spring is fixed to the inner side wall of the crushing box. The first cam is located below the hinge point of the connecting rod and the swing rod and is located to the left of the swing rod. A knocking block is fixed to the upper right side wall of the swing rod and abuts against the screen.

[0009] Preferably, it also includes a second cam and a push switch. The front end of the first rotating shaft is fixed with the second cam, which is located outside the crushing box. The front side wall of the lower part of the crushing box is fixed with a push switch, which is located to the right of the second cam. The push switch is electrically connected to the cooling component and is used to control the opening and closing of the cooling component.

[0010] Preferably, the cooling component includes a water pump, an inlet pipe, an outlet pipe, a water collection ring, and atomizing nozzles. The water pump is fixed to the top of the connecting plate and is electrically connected to a push switch. The water collection ring is fixed to the bottom of the connecting plate. The inlet pipe and the outlet pipe are fixedly connected to the water pump. The inlet pipe is connected to an external water tank, and the outlet pipe is connected to the water collection ring. Several atomizing nozzles are connected at equal intervals along the circumference at the bottom of the water collection ring.

[0011] Preferably, the transmission assembly includes a three-groove drive wheel, a first synchronous belt, a first driven wheel, a second synchronous belt, a second driven wheel, a third synchronous belt, and a third driven wheel. The three-groove drive wheel is connected to a first motor. The first driven wheel is fixed to the crushing roller assembly on the left side and is driven by the three-groove drive wheel through the first synchronous belt. The second driven wheel is fixed to the crushing roller assembly on the right side and is driven by the three-groove drive wheel through the second synchronous belt. The third driven wheel is fixed to the front end of the first rotating shaft and is driven by the three-groove drive wheel through the third synchronous belt.

[0012] Preferably, the crushing roller assembly includes two roller sections with identical structures, each including a second bearing seat, a second rotating shaft, a crushing roller body, and a gear. Second bearing seats are fixed to the front and rear side walls of the crushing box. The second rotating shaft passes through the two second bearing seats and the front and rear side walls of the crushing box. A gear is fixed to the rear end of the second rotating shaft. The gears of the two roller sections mesh with each other. A first driven wheel is fixed to the front end of the right second rotating shaft of the left crushing roller assembly, and a second driven wheel is fixed to the front end of the left second rotating shaft of the right crushing roller assembly. The crushing blade assembly includes a second motor, a third rotating shaft, a first blade, and a second blade. The second motor is fixed to the top of the connecting plate, and a third rotating shaft is fixed to the bottom end of the second motor. The lower part of the third rotating shaft extends to the middle of the crushing box and is fixed with several first blades. Several second blades are fixed at equal intervals along the circumference of the inner side wall of the middle of the crushing box. The second blades are offset from the first blades, and the water spray direction of the atomizing nozzle is directed towards the second blades.

[0013] This invention also provides a method for processing waste circuit boards, which uses the above-mentioned waste circuit board processing system for recycling, including the following steps: the circuit board substrate is fed into a crushing device to be crushed into particles, and the particles are cooled during the crushing process. The crushed particles are fed into a dehydration device to be dehydrated and filtered, and then mixed with oxides so that the particles are covered with a layer of oxides. Then, the particles are placed in a microwave pyrolysis furnace and microwaved at a temperature of 500℃-600℃ for 25-35 minutes. The high-temperature pyrolysis gas comes into contact with the oxides to generate corresponding halides, which remain in the solid phase. The gas phase is rapidly cooled through a heat exchanger and then sent to an absorption tower. The acidic gas in the gas phase is absorbed by a washing liquid. The gas exiting the absorption tower enters the adsorption system. The gas adsorbed by the adsorption system is discharged to the chimney and discharged from the chimney. The adsorption system is washed by hot air. The desorbed gas generated by the adsorption system enters the incineration system for incineration. Part of the gas generated after incineration is discharged to the chimney and discharged from the chimney, and the other part is used as the washing gas of the adsorption system.

[0014] Preferably, the particle size of the crushed particles is 0.1-1 mm, the moisture content of the dehydrated particles is ≤5‰, the oxide is calcium oxide, calcium carbonate or aluminum oxide, the particle size of the oxide is 100-150 μm, the molar ratio of oxide to bromine is 1.1-1.5:1, the washing liquid is sodium hydroxide solution, sodium carbonate solution or waste alkali liquid, the adsorption system is activated carbon adsorption system or zeolite molecular sieve, and the temperature of the pyrolysis gas after rapid cooling by heat exchanger is <200℃.

[0015] The beneficial effects of this invention are as follows:

[0016] 1. The microwave high-temperature pyrolysis + oxide absorption process is used to separate the circuit board metal from the substrate, which can effectively reduce the generation of gases such as dioxins.

[0017] 2. Based on dual crushing, a screening component is combined to achieve both crushing and screening of circuit boards, meeting the particle size requirements. The screening step is directly integrated into the crushing device, eliminating the need for two separate machines and making the process more convenient.

[0018] 3. The particle size of the collected particles can be controlled by the sieving specifications of the screen. The screen and the collection box are connected by threads, which facilitates the replacement of the screen. The collection box is fixed with bolts, which also allows the collection box to be disassembled for easy screen replacement.

[0019] 4. By linking the transmission components with the crushing roller group and the first rotating shaft, a first motor drives the rotation of the three parts, which not only realizes the crushing operation, but also achieves anti-clogging treatment. The design is ingenious.

[0020] 5. Based on the above-mentioned crushing operation and anti-clogging treatment achieved by a single motor, the linkage between the second cam and the push switch also achieves intermittent cooling and reduces energy consumption.

[0021] 6. Cooling is achieved during the secondary crushing process to prevent the formation of dioxins at high temperatures. The use of a water collection ring combined with atomizing nozzles ensures more comprehensive water spraying and improves the cooling effect.

[0022] 7. Use two different crushing methods to ensure the crushed particle size. Attached Figure Description

[0023] Figure 1 This is a system block diagram of the present invention.

[0024] Figure 2 This is a cross-sectional structural diagram of the present invention.

[0025] Figure 3 yes Figure 2 An enlarged diagram of A in the diagram.

[0026] Figure 4 This is a top view of the structure of the present invention.

[0027] Figure 5 This is a schematic diagram of the main structure of the present invention.

[0028] Figure 6 yes Figure 5 Enlarged diagram of B in the diagram.

[0029] Figure 7 This is a schematic diagram of the left-side structure of the first rotating shaft and its structure according to the present invention.

[0030] The labels in the attached diagram are as follows: 100-crushing device, 200-dehydration device, 300-mixer, 400-microwave pyrolysis furnace, 500-heat exchanger, 600-absorption tower, 700-adsorption system, 800-incineration system, 900-chimney, 1-mounting frame, 2-first motor, 3-roller section, 4-crushing box, 5-transmission assembly, 6-crushing blade assembly, 7-fan, 8-screening assembly, 9-cooling assembly, 10-connecting plate, 11-partition plate, 81-screen, 82-collection box, 83-mounting plate, 84-bolt, 41-through hole, 12-first rotating shaft, 13-first bearing seat, 14- 15-Connecting rod, 16-Swing rod, 17-Knocking block, 18-Spring, 19-Second cam, 20-Push switch, 91-Water pump, 92-Inlet pipe, 93-Outlet pipe, 94-Water collecting ring, 95-Atomizing nozzle, 51-Three-slot drive wheel, 52-First synchronous belt, 53-First driven wheel, 54-Second synchronous belt, 55-Second driven wheel, 56-Third synchronous belt, 57-Third driven wheel, 31-Second bearing seat, 32-Second rotating shaft, 33-Crushing roller body, 34-Gear, 61-Second motor, 62-Third rotating shaft, 63-First blade, 64-Second blade. Detailed Implementation

[0031] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments.

[0032] Contents not described in detail in this specification are prior art known to those skilled in the art. In the description of this invention, it should be understood that terms such as "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, terms such as "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0033] like Figures 1 to 7 As shown, the waste circuit board processing system provided in this embodiment includes a crushing device 100, a dehydration device 200, a mixer 300, a microwave pyrolysis furnace 400, a heat exchanger 500, an absorption tower 600, an adsorption system 700, an incineration system 800, and a chimney 900 arranged sequentially along the processing direction. The desorbed gas outlet of the adsorption system 700 is connected to the incineration system 800 through a pipe, and the exhaust port of the adsorption system 700 is connected to the chimney 900 through a pipe. The exhaust port of the incineration system 800 is connected to the chimney 900 and the adsorption system 700 through pipes respectively.

[0034] This embodiment also provides a method for processing waste circuit boards, which uses the above-mentioned waste circuit board processing system for recycling, and includes the following steps:

[0035] The circuit board substrate is fed into a crushing device 100 and crushed into particles with a diameter of 1 mm to increase the surface area. During the crushing process, water spray cooling is used to prevent the formation of dioxins at high temperatures. The crushed particles are then sent to a dehydration device 200 for dehydration and filtration, with the moisture content of the dehydrated particles ≤5‰. They are then mixed with an oxide; in this embodiment, the oxide is calcium oxide with a particle size of 100 μm, and the molar ratio of calcium oxide to bromine is 1.1:1. After mixing, a layer of calcium oxide coats the particles. The particles are then placed in a microwave pyrolysis furnace 400 and microwaved at 500°C for 30 minutes. The high-temperature pyrolysis gas contacts the calcium oxide, generating corresponding halides that remain in the solid phase. This microwave + oxide high-temperature pyrolysis process separates the metal from the matrix, and the halogen-containing gases are absorbed by the oxide, reducing the dioxin content in the volatile gas. The gas phase is then rapidly cooled to 180°C through a heat exchanger 500 to further reduce the formation of dioxin-like gases. The gas is then fed into absorption tower 600. Inside absorption tower 600, polycyclic aromatic hydrocarbon pollutants such as hydrogen chloride, hydrogen bromide, and dioxins diffuse to the liquid phase at the gas-liquid interface and are absorbed by the liquid phase. The gas exiting absorption tower 600 enters a zeolite molecular sieve. After the volatile organic waste gas is adsorbed by the zeolite molecular sieve, the gas is discharged to chimney 900 and then externally discharged. The zeolite molecular sieve is then washed with hot air. The high-temperature desorbed gas generated by the zeolite molecular sieve enters the incineration system 800 for incineration, producing carbon dioxide and water. Part of the gas produced after incineration is discharged to chimney 900 and externally discharged, while the other part is used as washing gas in the adsorption system 700. This invention uses microwave high-temperature pyrolysis + oxide absorption technology to separate the circuit board metal from the substrate, which can effectively reduce the generation of gases such as dioxins.

[0036] The crushing device 100 includes a mounting frame 1, a crushing box 4, crushing roller sets, a first motor 2, a transmission assembly 5, a crushing blade assembly 6, a blower 7, a screening assembly 8, a connecting plate 10, and a cooling assembly 9. The crushing box 4 is fixed to the mounting frame 1. The upper part of the crushing box 4 has two partitions 11, which divide the upper space inside the crushing box 4 into three independent spaces. Crushing roller sets are installed on both the left and right sides of the upper part of the crushing box 4. The crushing ends of the two crushing roller sets are located in the left and right independent spaces respectively. A first motor 2 is fixed to the front side wall of the upper part of the crushing box 4. Motor 2, the first motor 2 is connected to the left and right crushing roller groups respectively through the transmission component 5. A connecting plate 10 is fixed in the independent space in the middle. A crushing blade group 6 and a cooling component 9 are fixed on the connecting plate 10. The crushing end of the crushing blade group 6 is located in the middle of the crushing box 4. The cooling end of the cooling component 9 is set towards the crushing end of the crushing blade group 6. A fan 7 is fixed on the mounting frame 1. The air outlet of the fan 7 passes through the left side wall of the crushing box 4 and extends to the lower part of the interior of the crushing box 4. The screening component 8 is set on the right side wall of the crushing box 4 and is set opposite to the air outlet of the fan 7.

[0037] During crushing operations, the first motor 2 is started, driving the crushing roller groups on both sides via the transmission assembly 5. The independent spaces on both sides of the crushing roller groups improve crushing efficiency and allow for separate crushing, enabling the feeding of different sized substrates into different roller groups, thus offering high applicability. The independent space in the middle provides both a space for the crushing blade assembly 6 to penetrate deep into the crushing chamber 4 and a cooling space for the cooling assembly 9 to facilitate cooling of the interior of the crushing chamber 4. The substrates, after initial crushing by the crushing roller groups, fall to the middle of the crushing chamber 4 and undergo secondary crushing by the crushing blade assembly 6. Two different crushing methods are used to ensure the correct particle size. The particles formed from the secondary crushing fall to the lower part of the crushing chamber 4 and are blown by the fan 7 to the screening assembly 8. The screening assembly 8 filters out particles with a diameter of 0.1-1mm and collects them for later use. Particles that do not meet the required diameter can be re-feeded into the crushing chamber 4 for further crushing until the required diameter is achieved. Because this system has requirements on the particle size of the particulate matter, a dual crushing process is employed, combined with a screening component 8, to achieve both crushing and screening of the circuit board, thus meeting the particle size requirements. The screening step is directly integrated into the crushing device 100, eliminating the need for two separate devices and making the process more convenient.

[0038] The screening component 8 includes a screen 81, a collection box 82, a mounting plate 83, and bolts 84. A through hole 41 is provided on the lower right side wall of the crushing box 4. The left side of the collection box 82 has a feed inlet, which is connected to the through hole 41. The screen 81 is screwed to the feed inlet. The bottom of the collection box 82 has a discharge port. Mounting plates 83 are fixed to the upper and lower side walls of the collection box 82. The mounting plates 83 are detachably fixed to the crushing box 4 by bolts 84.

[0039] The particle size of the collected particles can be controlled by the sieving specifications of the screen 81. The screen 81 and the collection box 82 are connected by threads, which facilitates the replacement of the screen 81. The collection box 82 is fixed by bolts 84, which also allows the collection box 82 to be disassembled, facilitating the replacement of the screen 81.

[0040] The system includes a first rotating shaft 12, a first bearing seat 13, a first cam 14, a connecting rod 15, a swing rod 16, a knocking block 17, and a spring 18. The first bearing seat 13 is fixed to the front side wall of the lower part of the crushing box 4. One end of the first rotating shaft 12 is connected to the transmission assembly 5. The other end of the first rotating shaft 12 passes through the first bearing seat 13 and the front side wall of the crushing box 4, and extends into the crushing box 4 where the first cam 14 is fixed. The connecting rod 15 is fixed to the inner side wall of the crushing box 4 below the through hole 41. The left end of the connecting rod 15 is hinged to the swing rod 16. The right side wall of the swing rod 16 is fixed to the lower part of the right side wall of the swing rod 16. The right end of the spring 18 is fixed to the inner side wall of the crushing box 4. The first cam 14 is located below the hinge point of the connecting rod 15 and the swing rod 16, and is located to the left of the swing rod 16. The right side wall of the upper part of the swing rod 16 is fixed to the knocking block 17, which abuts against the screen 81.

[0041] While driving the crushing rollers on both sides for crushing operations, the transmission assembly 5 also drives the first rotating shaft 12 to rotate, which in turn drives the first cam 14 to rotate. The first cam 14 intermittently pushes the lower part of the swing rod 16 to the right, causing the spring 18 to contract and the upper part of the swing rod 16 to move to the left, moving the striking block 17 to the left away from the screen 81. When the distal end of the first cam 14 leaves the swing rod 16, the spring 18 extends, pushing the lower part of the swing rod 16 to the left, causing the upper part of the swing rod 16 to move to the right, driving the striking block 17 to move to the right and strike the screen 81, causing the particles attached to the screen 81 to be shaken off, preventing the screen 81 from clogging. Through the linkage between the transmission assembly 5, the crushing rollers, and the first rotating shaft 12, a single motor 2 drives the rotation of three parts, achieving both crushing operations and anti-clogging treatment – ​​a clever design.

[0042] It also includes a second cam 19 and a push switch 20. The front end of the first rotating shaft 12 is fixed with the second cam 19, which is located outside the crushing box 4. The front side wall of the lower part of the crushing box 4 is fixed with the push switch 20, which is located to the right of the second cam 19. The push switch 20 is electrically connected to the cooling component 9 and is used to control the opening and closing of the cooling component 9.

[0043] While the first rotating shaft 12 drives the first cam 14 to rotate, it also drives the second cam 19 to rotate. During the rotation of the second cam 19, the press switch 20 is pressed intermittently, causing the cooling component 9 to be turned on intermittently, thereby achieving cooling and reducing energy consumption. Based on the above-mentioned crushing operation and anti-clogging treatment achieved by a single motor, the linkage between the second cam 19 and the press switch 20 also achieves the effect of intermittent cooling and reducing energy consumption.

[0044] The cooling component 9 includes a water pump 91, an inlet pipe 92, an outlet pipe 93, a water collection ring 94, and atomizing nozzles 95. The water pump 91 is fixed on the top of the connecting plate 10 and is electrically connected to the push switch 20. The water collection ring 94 is fixed on the bottom of the connecting plate 10. The inlet pipe 92 and the outlet pipe 93 are fixedly connected to the water pump 91. The inlet pipe 92 is connected to an external water tank, and the outlet pipe 93 is connected to the water collection ring 94. Several atomizing nozzles 95 are equidistantly connected to the bottom of the water collection ring 94 along the circumference.

[0045] When the second cam 19 presses the press switch 20, the water pump 91 starts, drawing water from the external water tank. The water flows through the outlet pipe 93 into the water collection ring 94, and is finally sprayed as atomized water droplets from the atomizing nozzle 95. These droplets are then sprayed onto the crushing end of the crushing blade assembly 6 through the independent central space, achieving cooling during the crushing process and preventing the formation of dioxins at high temperatures. The arrangement of the water collection ring 94 combined with the atomizing nozzle 95 ensures more comprehensive water spraying and improves the cooling effect.

[0046] The transmission assembly 5 includes a three-groove drive wheel 51, a first synchronous belt 52, a first driven wheel 53, a second synchronous belt 54, a second driven wheel 55, a third synchronous belt 56, and a third driven wheel 57. The three-groove drive wheel 51 is connected to the first motor 2. The first driven wheel 53 is fixed to the crushing roller group located on the left side and is connected to the three-groove drive wheel 51 through the first synchronous belt 52. The second driven wheel 55 is fixed to the crushing roller group located on the right side and is connected to the three-groove drive wheel 51 through the second synchronous belt 54. The third driven wheel 57 is fixed to the front end of the first rotating shaft 12 and is connected to the three-groove drive wheel 51 through the third synchronous belt 56.

[0047] The first motor 2 drives the three-slot drive wheel 51 to rotate, which in turn drives the first driven wheel 53 to rotate via the first synchronous belt 52, causing the crushing roller group on the left to rotate and perform crushing operations. Simultaneously, the second synchronous belt 54 drives the second driven wheel 55 to rotate, causing the crushing roller group on the right to rotate and perform crushing operations. At the same time, the third synchronous belt 56 drives the third driven wheel 57 to rotate, causing the first rotating shaft 12 to rotate. The first rotating shaft 12 simultaneously drives the first cam 14 and the second cam 19 to rotate, achieving intermittent striking of the screen 81 for anti-clogging treatment and intermittent activation of the water pump 91 for cooling treatment.

[0048] The crushing roller assembly includes two roller sections 3, which have the same structure. Each roller section 3 includes a second bearing seat 31, a second rotating shaft 32, a crushing roller body 33, and a gear 34. The front and rear side walls of the crushing box 4 are fixed with second bearing seats 31. The second rotating shaft 32 passes through the two second bearing seats 31 and the front and rear side walls of the crushing box 4. The rear end of the second rotating shaft 32 is fixed with a gear 34. The gears 34 of the two roller sections 3 mesh with each other. The front end of the right second rotating shaft 32 of the crushing roller assembly on the left side is fixed with a first driven wheel 53, and the front end of the left second rotating shaft 32 of the crushing roller assembly on the right side is fixed with a second driven wheel 55.

[0049] The rotation of the first driven wheel 53 drives the second rotating shaft 32 on the right side of the left-side crushing roller group to rotate, causing the crushing roller body 33 on it to rotate. Simultaneously, this drives the gear 34 at its rear end to rotate, meshing with the gear 34 on its left side. This causes the second rotating shaft 32 on the left side of the left-side crushing roller group to rotate in the opposite direction, driving the crushing roller body 33 on it to rotate in the opposite direction. The two work together to achieve the initial crushing process on the substrate. The crushing principle of the right-side crushing roller group is the same as that of the left-side crushing roller group, and will not be described in detail here.

[0050] The crushing blade assembly 6 includes a second motor 61, a third rotating shaft 62, a first blade 63, and a second blade 64. The second motor 61 is fixed to the top of the connecting plate 10, and the bottom end of the second motor 61 is fixed to the third rotating shaft 62. The lower part of the third rotating shaft 62 extends to the middle of the crushing box 4 and is fixed with several first blades 63. Several second blades 64 are fixed at equal intervals along the circumference of the inner sidewall of the middle of the crushing box 4. The second blades 64 are offset from the first blades 63, and the water spraying direction of the atomizing nozzle 95 is set towards the second blades 64.

[0051] During the crushing operation, the second motor 61 rotates, driving the third rotating shaft 62 to rotate, causing the first blade 63 to rotate. In cooperation with the fixed second blade 64, a secondary crushing operation is achieved on the substrate to meet the particle size requirements.

[0052] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A waste circuit board processing system, characterized in that: It includes a crushing device, a dewatering device, a mixer, a microwave pyrolysis furnace, a heat exchanger, an absorption tower, an adsorption system, an incineration system, and a chimney, arranged sequentially along the processing direction; The desorbed gas outlet of the adsorption system is connected to the incineration system via a pipeline, and the exhaust port of the adsorption system is connected to the chimney via a pipeline. The exhaust outlet of the incineration system is connected to the chimney and the adsorption system via pipes. The crushing device includes a mounting frame, a crushing box, a crushing roller assembly, a first motor, a transmission assembly, a crushing blade assembly, a blower, a screening assembly, a connecting plate, and a cooling assembly; The crushing box is fixed to the mounting frame; The upper part of the crushing box has two partitions, which divide the upper space inside the crushing box into three independent spaces. Crushing roller sets are provided on both the left and right sides of the upper part of the crushing box, and the crushing ends of the two crushing roller sets are located in two independent spaces on the left and right respectively. A first motor is fixed to the front side wall of the upper part of the crushing box. The first motor is connected to the left and right crushing roller groups respectively through a transmission assembly. A connecting plate is fixed in the independent space in the middle, and a crushing blade assembly and a cooling component are fixed on the connecting plate. The crushing end of the crushing blade assembly is located in the middle of the crushing box, and the cooling end of the cooling component is set towards the crushing end of the crushing blade assembly. A fan is fixed on the mounting frame. The air outlet of the fan passes through the left side wall of the crushing box and extends to the lower part of the crushing box. The screening component is located on the right side wall of the crushing box and is arranged opposite to the air outlet of the fan. The screening assembly includes a screen, a collection box, a mounting plate, and bolts; A through hole is provided at the bottom of the right side wall of the crushing box; The collection box has a feed inlet on the left side, which is connected to the through hole. A screen is screwed into the feed inlet, and the bottom of the collection box has a discharge outlet. Mounting plates are fixed to the upper and lower side walls of the collection box, and the mounting plates are detachably fixed to the crushing box by bolts; It also includes a first rotating shaft, a first bearing housing, a first cam, a connecting rod, a swing arm, a knocking block, and a spring; A first bearing seat is fixed to the front side wall of the lower part of the crushing box. One end of the first rotating shaft is connected to the transmission assembly. The other end of the first rotating shaft passes through the first bearing seat and the front side wall of the crushing box, and extends into the interior of the crushing box where a first cam is fixed. A connecting rod is fixed to the inner wall of the crushing box below the through hole. A swing rod is hinged to the left end of the connecting rod. A spring is fixed to the lower right side wall of the swing rod. The right end of the spring is fixed to the inner wall of the crushing box. The first cam is located below the hinge point of the connecting rod and the swing rod and is located to the left of the swing rod. A knocking block is fixed to the upper right side wall of the swing rod. The knocking block abuts against the screen. It also includes a second cam and a push-button switch; A second cam is fixed to the front end of the first rotating shaft, and the second cam is located outside the crushing box; A push-button switch is fixed to the front side wall of the lower part of the crushing box. The push-button switch is located on the right side of the second cam and is electrically connected to the cooling component to control the opening and closing of the cooling component.

2. The waste circuit board processing system according to claim 1, characterized in that: The cooling assembly includes a water pump, an inlet pipe, an outlet pipe, a water collection ring, and an atomizing nozzle; A water pump is fixed to the top of the connecting plate and is electrically connected to a push-button switch. A water collection ring is fixed to the bottom of the connecting plate. An inlet pipe and an outlet pipe are fixedly connected to the water pump. The inlet pipe is connected to an external water tank, and the outlet pipe is connected to the water collection ring. Several atomizing nozzles are equidistantly connected to the bottom of the water collection ring along the circumference.

3. The waste circuit board processing system according to claim 2, characterized in that: The transmission assembly includes a three-groove drive pulley, a first synchronous belt, a first driven pulley, a second synchronous belt, a second driven pulley, a third synchronous belt, and a third driven pulley; The three-slot drive wheel is connected to the first motor; The first driven wheel is fixed to the crushing roller group located on the left side and is connected to the three-groove driving wheel through the first synchronous belt; The second driven wheel is fixed to the crushing roller group located on the right side and is connected to the three-groove driving wheel via the second synchronous belt; The third driven wheel is fixed to the front end of the first rotating shaft and is connected to the three-groove driving wheel via a third synchronous belt.

4. The waste circuit board processing system according to claim 3, characterized in that: The crushing roller assembly includes two roller sections with identical structures, each including a second bearing seat, a second rotating shaft, a crushing roller body, and gears. The front and rear side walls of the crushing box are both fixed with second bearing seats. The second rotating shaft passes through the two second bearing seats and the front and rear side walls of the crushing box. The rear end of the second rotating shaft is fixed with a gear. The gears of the two rollers mesh with each other. The front end of the right second rotating shaft of the crushing roller group on the left side is fixed with a first driven wheel. The front end of the left second rotating shaft of the crushing roller group on the right side is fixed with a second driven wheel. The crusher assembly includes a second motor, a third rotating shaft, a first blade, and a second blade; The second motor is fixed to the top of the connecting plate, and a third rotating shaft is fixed to the bottom of the second motor. The lower part of the third rotating shaft extends to the middle of the crushing box and is fixed with several first blades. A number of second blades are fixed at equal intervals along the circumference of the inner sidewall of the middle part of the crushing box, and the second blades are offset from the first blades. The water spray direction of the atomizing nozzle is set towards the direction of the second blade.

5. A method for processing waste circuit boards, characterized in that, The recycling process using the waste circuit board processing system according to any one of claims 1-4 includes the following steps: The circuit board substrate is fed into a crushing device to be crushed into particles, and the particles are cooled during the crushing process. The crushed particles are then sent to a dehydration device to be dehydrated and filtered, and then mixed with oxides to coat the particles with a layer of oxides. The particles are then placed in a microwave pyrolysis furnace and microwaved at 500℃-600℃ for 25-35 minutes. The high-temperature pyrolysis gas comes into contact with the oxides to generate the corresponding halides, which remain in the solid phase. The gas phase is rapidly cooled through a heat exchanger and then sent to an absorption tower. The acidic gases in the gas phase are absorbed by the washing liquid. The gas exiting the absorption tower enters the adsorption system. The gas adsorbed by the adsorption system is discharged to the chimney and discharged outside the chimney. The adsorption system is washed by hot air. The desorbed gas generated by the adsorption system enters the incineration system for incineration. Part of the gas generated after incineration is discharged to the chimney and discharged outside the chimney, while the other part is used as the washing gas of the adsorption system.

6. The waste circuit board disposal method according to claim 5, characterized in that: The particle size of the crushed particles is 0.1-1 mm; The moisture content of the dehydrated granules is ≤5‰; The oxide is calcium oxide, calcium carbonate, or aluminum oxide, with a particle size of 100-150 μm and a molar ratio of oxide to bromine of 1.1-1.5:

1. The washing solution is a sodium hydroxide solution, a sodium carbonate solution, or waste alkaline solution; The adsorption system is either an activated carbon adsorption system or a zeolite molecular sieve; The temperature of the pyrolysis gas after rapid cooling by the heat exchanger is <200℃.

Images