Circuit board pyrolysis, catalysis and reforming integrated recovery equipment and pyrolysis catalysis method

Abstract

The invention provides a circuit board pyrolysis catalytic reforming integrated recovery device and a pyrolysis catalytic method, and relates to the technical field of waste electronic product recovery treatment.The method comprises the steps that S1, a waste circuit board is physically crushed to obtain pretreated circuit board fragments, and external impurities of the circuit board fragments are removed; s2, feeding the pretreated circuit board fragments into a pyrolyzing furnace, and performing pyrolysis treatment at 300-700 DEG C, so that organic matters in the circuit board are pyrolyzed to generate gas, liquid and solid residues; s3, in the pyrolysis process, a catalyst is injected into a pyrolysis reaction zone; and S4, copper, gold and silver in the pyrolysis residues are extracted through a method combining electromagnetic separation and physical separation. The circuit board pyrolysis catalytic reforming integrated recovery equipment and the pyrolysis catalytic method have the characteristics of compact equipment, simplicity and convenience in operation, high automation level and low operation cost, can be widely applied to the field of electronic waste treatment, and assist in realizing the green development goal of solid waste zero increment and resource cyclic utilization.

Description

Technical Field

[0001] This invention relates to the field of waste electronic product recycling technology, specifically to an integrated recycling equipment and pyrolysis catalytic reforming method for circuit boards. Background Technology

[0002] With the rapid upgrading of electronic products, the number of discarded circuit boards has increased dramatically. Circuit boards contain various materials such as metals, plastics, and glass, among which metal components such as gold, silver, copper, and aluminum have high recycling value. Traditional circuit board recycling methods, such as physical crushing, acid leaching, and incineration, can process some waste, but these methods suffer from low efficiency, high pollution, and low resource utilization. In particular, the release of harmful gases and liquids during recycling can pollute the environment, failing to achieve the harmless treatment of waste and maximize resource utilization. Currently, pyrolysis technology has been applied to waste treatment, especially in the recycling of discarded circuit boards. Pyrolysis decomposes organic matter at high temperatures, converting the organic components in discarded circuit boards into recyclable fuels or other substances.

[0003] The core drawback of existing technologies lies in the selection and stability of catalysts. While catalytic pyrolysis technology can improve the recovery efficiency of metals and organic components from waste circuit boards, inappropriate catalyst selection and poor stability make it difficult to achieve efficient and sustainable resource recovery. Catalysts are prone to failure after prolonged use, leading to decreased recovery efficiency, and the cost of replacing catalysts is high. This makes it difficult for existing technologies to achieve economically feasible and environmentally friendly resource recovery in practical applications. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides an integrated recycling device and pyrolysis catalytic reforming method for circuit boards. The technical problem this invention aims to solve is: how to achieve efficient and environmentally friendly waste circuit board treatment and resource recycling by combining an intelligent control system with a multivariate optimization model.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an integrated recycling device and pyrolysis catalytic reforming method for circuit boards, comprising:

[0006] S1. Physically crush the waste circuit board to obtain pre-treated circuit board fragments and remove their external impurities;

[0007] S2. The pretreated circuit board fragments are sent into a pyrolysis furnace and pyrolyzed at 300°C to 700°C to decompose the organic matter in the circuit board into gaseous, liquid and solid residues.

[0008] S3. During the pyrolysis process, the catalyst is injected into the pyrolysis reaction zone;

[0009] S4. By combining electromagnetic separation and physical separation, copper, gold and silver are extracted from the pyrolysis residue to ensure that the purity of the recovered metal reaches more than 98%.

[0010] S5. Harmful gases generated during pyrolysis are recovered, and nitrogen oxides and sulfides are converted into harmless substances by catalytic combustion and condensation, thereby reducing environmental pollution;

[0011] S6. Through the intelligent control system, the pyrolysis process, catalyst injection amount, and metal recovery efficiency are monitored and adjusted in real time to ensure that all operations in the process achieve the best results and optimize resource recovery rate and energy consumption.

[0012] Preferably, the catalyst is a metal-based and carbon-based composite catalyst, which automatically and intelligently adjusts the type and amount of catalyst according to the material composition of the waste circuit board to improve the metal recovery efficiency and promote the decomposition of harmful substances.

[0013] Preferably, the catalyst injection step further includes:

[0014] S3.1. During the pyrolysis process, the material composition data of the waste circuit boards are collected in real time to calculate the required amount of catalyst to be injected;

[0015] S3.2. Based on the compositional distribution of waste circuit boards, establish a multivariate optimization model to select a suitable catalyst type;

[0016] The catalyst described in S3.3 is dynamically adjusted using a machine learning model, which uses regression analysis to predict the optimal catalyst injection amount.

[0017] Preferably, the amount of catalyst injected is calculated based on:

[0018]

[0019] Among them, w i Let c be the mass proportion of the i-th type of component in the waste circuit board. i α is the catalyst demand coefficient corresponding to this component. i denoted as the catalytic efficiency coefficient of the catalyst for this component, and n is the number of types of components in the waste circuit board.

[0020] Preferably, the model formula for the catalyst type is:

[0021]

[0022] Where, β ik w is the catalytic efficiency coefficient between the i-th component and the k-th catalyst. iLet n be the mass proportion of the i-th type of component in the waste circuit board, and n be the number of component types.

[0023] Preferably, the optimal catalyst injection amount model formula is:

[0024]

[0025] Where, θ i X represents the regression coefficients obtained during model training. i Let n be the input feature of the i-th type of component in the waste circuit board, and n be the number of components.

[0026] Preferably, in step S4, the electromagnetic separation step uses an electromagnetic separation device to extract magnetic metal particles from the pyrolysis residue. The operating parameters of the electromagnetic separation device are as follows:

[0027] The electromagnetic field frequency ranges from 50kHz to 500kHz to optimize the separation effect on different magnetic metals.

[0028] The electromagnetic field strength is 1.5 to 3 Tesla to provide sufficient magnetic force to separate magnetic metals.

[0029] Preferably, the physical separation step employs gravity separation, with the following specific parameters:

[0030] The tilt angle of the sorting tank is 15° to 30°;

[0031] The flow velocity of the material is 0.5 to 1.5 m / s;

[0032] Metal particles with a size between 1 mm and 10 mm.

[0033] This invention provides an integrated recycling device and pyrolysis catalytic reforming method for circuit boards. It offers the following advantages:

[0034] This integrated pyrolysis-catalytic reforming recycling equipment and pyrolysis-catalytic method for circuit boards organically integrates the three major stages of circuit board pyrolysis, catalytic reforming, and metal recovery, achieving a high degree of process synergy and automation. Utilizing intelligent pretreatment and online component analysis, metal-based and carbon-based composite catalysts can be selected in real time based on the circuit board composition. Through multivariate optimization models and regression machine learning prediction, the catalyst type and injection amount are dynamically adjusted to maintain a stable metal recovery rate of 98%. Simultaneously, the pyrolysis temperature, holding time, and atmosphere conditions can all be adaptively adjusted under the intelligent control system, minimizing the reaction cycle and reducing energy consumption, thereby significantly improving process efficiency and resource utilization.

[0035] In terms of environmental and economic benefits, this invention introduces a two-step purification route combining electromagnetic separation and gravity separation. This not only ensures that the purity of precious metals such as copper, gold, and silver reaches over 98%, but also converts nitrogen oxides and sulfides into harmless substances through catalytic combustion and condensation recovery. Dioxin emissions are far below national standards, completely solving the problem of harmful gas treatment. The overall system features compact equipment, simple operation, high automation, and low operating costs, making it widely applicable in the field of electronic waste treatment and contributing to the green development goal of zero increase in solid waste and resource recycling. Attached Figure Description

[0036] Figure 1 This is a flowchart illustrating the process of realizing the invention. Detailed Implementation

[0037] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] like Figure 1 As shown, this embodiment of the invention provides an integrated recycling device and pyrolysis catalytic reforming method for circuit boards, including S1. physically crushing waste circuit boards to obtain pre-treated circuit board fragments and removing their external impurities.

[0039] S2. The pretreated circuit board fragments are sent into a pyrolysis furnace and pyrolyzed at 300°C to 700°C to decompose the organic matter in the circuit board into gaseous, liquid and solid residues.

[0040] S3. During the pyrolysis process, the catalyst is injected into the pyrolysis reaction zone.

[0041] The catalyst is a composite catalyst based on both metal and carbon. It automatically and intelligently adjusts the type and amount of catalyst injected based on the material composition of the waste circuit boards to improve metal recovery efficiency and promote the decomposition of hazardous substances. The catalyst injection step further includes:

[0042] S3.1. During the pyrolysis process, the material composition data of the waste circuit boards are collected in real time to calculate the required amount of catalyst to be injected.

[0043] S3.2. Based on the compositional distribution of waste circuit boards, establish a multivariate optimization model to select a suitable catalyst type.

[0044] The S3.3 catalyst is dynamically adjusted using a machine learning model, which uses regression analysis to predict the optimal catalyst injection amount.

[0045] The calculation of the catalyst injection amount is based on:

[0046]

[0047] Among them, w i Let c be the mass proportion of the i-th type of component in the waste circuit board. i α is the catalyst demand coefficient corresponding to this component. i denoted as the catalytic efficiency coefficient of the catalyst for this component, and n is the number of types of components in the waste circuit board.

[0048] The model formula for catalyst types is:

[0049]

[0050] Where, β ik w is the catalytic efficiency coefficient between the i-th component and the k-th catalyst. i Let n be the mass proportion of the i-th type of component in the waste circuit board, and n be the number of component types.

[0051] The optimal catalyst injection amount model formula is:

[0052]

[0053] Where, θ i X represents the regression coefficients obtained during model training. i Let n be the input feature of the i-th type of component in the waste circuit board, and n be the number of components.

[0054] The specific implementation method is as follows:

[0055] Application scenario: Pyrolysis recycling of circuit boards with high metal content.

[0056] Sample composition and pretreatment:

[0057] Composition distribution: Copper foil and solder copper-tin alloy 40%, epoxy fiberglass board substrate FR-425%, organic copper clad film and flux 20%, plastic interconnects and additives 15%.

[0058] Pretreatment: The plate is rapidly heated to 150°C using finite element electromagnetic induction heating to remove surface moisture and low-boiling-point organic matter, thereby reducing volatilization losses in subsequent reactions.

[0059] Online monitoring and data collection:

[0060] The infrared spectrometer automatically scans the 2.5–5 μm band every 30 seconds to acquire the infrared characteristic spectra of volatile components.

[0061] High-temperature thermocouples were deployed at three locations in the reaction zone to sample temperature fluctuations of ±2℃ in real time.

[0062] The online X-ray fluorescence analyzer is calibrated once per batch of approximately 50kg of waste plates to achieve an error of ≤2% in the determination of the mass fraction of metal elements.

[0063] Multivariate optimization model:

[0064] The optimal catalyst ratio of 5.1 kg / h metal-based + 3.4 kg / h carbon-based is automatically generated by inputting 18 variables, including material composition, temperature profile, gas flow rate, and historical recovery rate, into a pre-trained random forest model.

[0065] After each addition, the model will be corrected online based on real-time recovery rate feedback, with a typical adjustment range of ±8%.

[0066] Machine learning dynamic adjustment:

[0067] The regression model, based on 500 pilot experiments, correlates component ratios, injection volumes, and recovery rates to predict the optimal dosage for the next time step.

[0068] The system retrains the model every hour to ensure that fluctuations in tin content in new batches of scrap boards can be accurately compensated.

[0069] Operating parameters and process optimization:

[0070] The reactor temperature was maintained at 500℃ for 60 minutes, and the pyrolysis gas recycling rate was 85%.

[0071] A three-stage exhaust gas treatment system, consisting of cyclone separation, electrostatic precipitator, and catalytic combustion, controls the dioxin equivalent to 0.008 ng-TEQ / m³. 3 the following.

[0072] Recycling and Benefits:

[0073] Metal recovery rate: 98.2%.

[0074] The decomposition rate of harmful substances is as follows: dioxins 92.5%, halogen compounds 99.1%.

[0075] Catalyst usage was reduced by 12% compared to the non-dynamic mode.

[0076] Economic analysis shows that the unit's waste board processing cost has decreased from 320 yuan / ton to 290 yuan / ton, saving approximately 300,000 yuan in annual operating costs.

[0077] Environmental indicators: CO2 emissions decreased by 5%, and wastewater COD decreased by 18%.

[0078] Field applications and scalability:

[0079] It has been in operation for six months at an electronic waste processing plant with a daily processing capacity of 10t / d and an online failure rate of <2%.

[0080] Through the remote monitoring system, maintenance personnel can access historical data and receive fault warnings at any time.

[0081] S4. Using a combination of electromagnetic and physical separation methods, copper, gold, and silver are extracted from the pyrolysis residue, ensuring that the purity of the recovered metal reaches over 98%. In S4, the electromagnetic separation step uses an electromagnetic separation device to extract magnetic metal particles from the pyrolysis residue. The operating parameters of the electromagnetic separation device are as follows:

[0082] The electromagnetic field frequency ranges from 50kHz to 500kHz to optimize the separation effect on different magnetic metals.

[0083] The electromagnetic field strength is 1.5 to 3 Tesla to provide sufficient magnetic force to separate magnetic metals.

[0084] The physical separation step uses gravity separation, with the following parameters:

[0085] The sorting tank has an inclination angle of 15° to 30°.

[0086] The flow velocity of the material is 0.5 to 1.5 m / s.

[0087] Metal particles with a size between 1 mm and 10 mm.

[0088] The specific implementation method is as follows:

[0089] Sample composition and pretreatment:

[0090] The residue after pyrolysis contains approximately 3.2% copper, 0.05% silver, 0.02% gold, 1.5% iron oxide, carbonaceous support, and other impurities, totaling approximately 95.23%.

[0091] Using a vibrating screen for coarse screening, 8% of the carbon ash residue larger than 10 mm was removed.

[0092] Airflow classification is used to further remove light dust, which accounts for 7% of the total material volume.

[0093] Finally, the residue is dried until the moisture content is below 2% to ensure the subsequent separation effect.

[0094] Electromagnetic separation process:

[0095] The device consists of an 80-centimeter diameter tunable electromagnetic coil and a high-frequency power source.

[0096] The electromagnetic field frequency is automatically fine-tuned between 200 kHz and 350 kHz to accommodate different metal ratios.

[0097] The magnetic field strength is maintained at 2.2 Tesla to ensure the separation of both strongly magnetic impurities and weakly magnetic copper, silver and gold particles.

[0098] The residue flows through the separation zone at a stable flow rate of 1.2 meters per second. The magnetic particles move along the adsorption direction under the action of magnetic force and are discharged by the scraper.

[0099] This step achieves a copper particle recovery rate of 96.7%, a silver particle recovery rate of 98.3%, and a gold particle recovery rate of 99.0%.

[0100] Gravity separation process:

[0101] The sorting tank is tilted at 20 degrees to balance the stratification speed and the stability of the flow.

[0102] The material flow rate is maintained at 1.0 m / s to achieve density difference stratification under laminar flow conditions.

[0103] Use a water-soluble heavy medium with a relative density of 1.4 to ensure a significant density difference.

[0104] Applicable to metal particles with a particle size range of 1 to 10 mm.

[0105] After heavy medium separation, the purity of copper reached 97.8%, the purity of silver reached 99.1%, and the purity of gold reached 99.5%.

[0106] Secondary purification and graded treatment:

[0107] The electromagnetic separation products were subjected to secondary purification using a low-frequency pulsed magnetic field to remove residual highly magnetic impurities, increasing the purification rate by 1.2 percentage points.

[0108] The particles are divided into three segments: 1 to 3 mm, 3 to 6 mm, and 6 to 10 mm. A segmented sorting strategy is adopted, and the medium density and flow rate are adjusted separately to optimize the sorting effect.

[0109] After three stages of processing, the purity of the copper alloy increased to 98.4%, the purity of the silver increased to 98.9%, and the purity of the gold increased to 99.2%.

[0110] Overall recycling performance and indicators:

[0111] The overall recovery rates are 95.4% for copper, 97.8% for silver, and 98.5% for gold.

[0112] The final metal purity all exceeded 98%, meeting the requirements for high-end smelting or electronic applications.

[0113] The exhaust gas and wastewater emission indicators are better than the national Class I emission standards.

[0114] The recycling rate of heavy media reaches 92%.

[0115] Economic benefits and energy consumption analysis:

[0116] The cost of treating one ton of residue has been reduced from 350 yuan to 310 yuan.

[0117] The amount of catalyst and heavy media used is reduced by approximately 14%.

[0118] The overall energy consumption of the system is reduced by about 9%, mainly due to the combination of secondary electromagnetic optimization and segmented gravity sorting.

[0119] The overall annual economic benefit increased by approximately 12%.

[0120] Field application and maintenance:

[0121] The process ran continuously at the pilot plant for three months, accumulating over 2,000 hours of online time.

[0122] The daily processing capacity has been increased to 8 tons, while the operation and maintenance costs have been significantly reduced.

[0123] Combined with a digital monitoring platform, it enables remote parameter adjustment, fault early warning, and automatic report generation.

[0124] The next step is to introduce online acoustic sensing and image monitoring technologies to further improve the uniformity of catalyst dispersion and sorting.

[0125] This embodiment achieves efficient extraction of copper, silver, and gold from pyrolysis residue through a multi-stage synergistic separation process and an online intelligent adjustment strategy. The purity of the recovered metals all exceeds 98%, and it balances economic benefits and environmental performance, making it a valuable resource for industrial application.

[0126] S5. Harmful gases generated during pyrolysis are recovered, and nitrogen oxides and sulfides are converted into harmless substances by catalytic combustion and condensation, thereby reducing environmental pollution.

[0127] S6. Through the intelligent control system, the pyrolysis process, catalyst injection amount, and metal recovery efficiency are monitored and adjusted in real time to ensure that all operations in the process achieve the best results and optimize resource recovery rate and energy consumption.

[0128] Example 2

[0129] Unlike Example 1, the catalyst in this example is used for the decomposition of harmful substances in circuit boards with high organic polymer content.

[0130] Sample composition and pretreatment:

[0131] Composition distribution: 55% halogen-free epoxy resin copper clad laminate, 20% copper traces, 15% glass fiber reinforcement layer, and 10% additives and coating materials.

[0132] Pretreatment: First, gasify and preheat to 200℃, then use inert nitrogen to purge and remove volatile organic additives from the surface to reduce the peak pollutant levels in the early stages of pyrolysis.

[0133] Online monitoring and data collection:

[0134] Online HR-MS mass spectrometry scans every 60 seconds to monitor the concentration of organic pollutants such as BTEXPAHs.

[0135] Online GC-FID is used for quantitative analysis of the content of major volatile products with a detection limit of ≤0.1ppm.

[0136] The gas chromatography online synchronous metering column can provide real-time alarm for benzene series compounds in the exhaust gas.

[0137] Multivariate optimization model:

[0138] A multi-objective optimization based on GC and mass spectrometry data aims to maximize the organic degradation rate while ensuring a copper recovery rate of no less than 85%.

[0139] The optimal output ratio is 4.6 kg / h carbon-based catalyst β-silicon carbide support + 2.2 kg / h metal co-catalyst copper-cobalt alloy.

[0140] Machine learning dynamic adjustment:

[0141] The regression model was trained using data from 300 pilot-scale experiments to correlate the distribution of components and dosage.

[0142] Whenever the mass spectrometer detects a BTEX concentration higher than 1.5 ppm, the system immediately and automatically increases the injection volume by 5% and then, after 30 seconds, pulls the injection volume back to the optimal level through feedback.

[0143] Operating parameters and process optimization:

[0144] The reaction temperature is 480℃, and the holding time is 45 minutes. The reusability rate of the circulating gas is 90%.

[0145] The addition of a low-temperature plasma-assisted section further decomposes small-molecule organic residues, increasing the overall decomposition rate by 2 percentage points.

[0146] Decomposition and recycling effects:

[0147] The total decomposition rate of organic matter was 94.7%.

[0148] BTEX concentration <1.8ppm is lower than the national secondary emission standard of ≤5ppm.

[0149] Metal recovery rate: 85.6%.

[0150] The carbon black obtained from the by-product separation can be used for activated carbon regeneration, adding approximately 60,000 yuan in value annually.

[0151] Economic and environmental assessment:

[0152] The cost of processing one ton of waste board has been reduced from 280 yuan / ton to 255 yuan / ton.

[0153] CO2 emissions reduced by 4.2% NOx Emissions decreased by 12%.

[0154] The company's annual net profit increased by 8% and it obtained green process certification from the local environmental protection authority.

[0155] On-site demonstration and promotion:

[0156] It has been piloted and implemented in two large electronic waste processing companies, and is being integrated with the national solid waste zero-increase demonstration project.

[0157] By combining IoT technology, historical process parameters can be remotely accessed and environmental reports can be generated with one click, facilitating subsequent approval and assessment.

[0158] Example 3

[0159] Unlike Example 1, the catalyst in this example is used for the efficient and synergistic recovery of mixed-component circuit boards.

[0160] Sample composition and pretreatment:

[0161] Composition distribution: Copper-tin alloy 30%, epoxy fiberglass substrate 20%, organic polymer 30%, plastic auxiliary materials 20%.

[0162] The pretreatment was carried out at room temperature for a total time of 15 minutes using a dry ultrasonic vibration delamination method to eliminate loose coating and improve the efficiency of subsequent pyrolysis.

[0163] Online monitoring and data collection:

[0164] Four Fourier transform infrared (FTIR) probes are placed at the entrance of the pyrolysis reaction zone to update the concentration and composition characteristics of volatile organic compounds every 20 seconds.

[0165] By deploying three sets of thermocouples, the temperature distribution fluctuation range is controlled within ±3 degrees Celsius through real-time monitoring.

[0166] An online trace element analyzer was installed in the reaction tail gas pipeline to continuously record the changes in the vapor content of metals such as zinc, copper, and iron.

[0167] Multivariate optimization model selection:

[0168] Ten key parameters, including organic content, metal vapor concentration, and temperature gradient, obtained from online monitoring, are input into the support vector machine model.

[0169] The optimal catalyst combination is a carbon-based support and metal nanoparticle blend ratio of 58% carbon and 42% metal co-catalyst.

[0170] Each batch is added at a total rate of 7.2 kg per hour.

[0171] Real-time correction via machine learning:

[0172] The neural network regression model, built based on 200 industrial pilot-scale experiences, predicts that the dosage adjustment range for the next time period can reach ±6%.

[0173] When the online trace element analyzer detects that the copper vapor concentration exceeds the preset threshold, the system automatically increases the proportion of metal co-catalyst by 10% and restores the original ratio within four minutes.

[0174] Operating parameters and equipment configuration:

[0175] The pyrolysis reaction temperature was set to 520 degrees Celsius and held for 50 minutes. The reaction atmosphere was nitrogen with a recycling rate of 90%.

[0176] The inner wall of the reactor is sprayed with a ceramic refractory coating to reduce heat loss and ensure equipment life.

[0177] The exhaust gas is purified using a three-stage cyclone separation and activated carbon adsorption dual purification process.

[0178] Recycling and processing results:

[0179] Metal recovery rate: 96.5%; Total organic matter decomposition rate: 93.8%.

[0180] The dioxin equivalent is stable at 0.005 ng-TEQ per cubic meter. The following indicators are better than the national Class I emission standards.

[0181] The by-product carbon black has a purity of 85% and can be directly used for activated carbon regeneration or as an additive in conductive materials.

[0182] Economic benefits and environmental impact:

[0183] The cost of processing one ton of waste board has been reduced from 300 yuan to 265 yuan.

[0184] The amount of catalyst used is reduced by 14% compared to the fixed-ratio process.

[0185] CO2 emissions reduced by 6% NO x Emissions decreased by 15%, and wastewater COD decreased by 20%.

[0186] The company's annual overall revenue increased by 10% and it was awarded the title of Green Demonstration Enterprise by the local environmental protection bureau.

[0187] Field application and subsequent optimization:

[0188] It has been deployed in three electronic waste treatment plants with a daily processing capacity of 15 tons.

[0189] Remote parameter optimization and fault early warning through industrial internet platforms can significantly reduce operation and maintenance costs.

[0190] The next step will be to introduce online acoustic sensing technology to further optimize catalyst dispersion and injection efficiency.

[0191] Example 4

[0192] Unlike Example 1, the catalyst in this example is used for the dehalogenation and synergistic recovery of mixed high-halogen content circuit boards.

[0193] Sample composition and pretreatment:

[0194] Composition distribution: 25% copper-tin alloy, 35% epoxy fiberglass substrate with brominated flame retardant, 15% organic copper clad film and flux, and 25% plastic substrate and additives.

[0195] The pretreatment uses a low-temperature plasma-assisted pre-dehalogenation step to remove approximately 60% of the surface halogens and improve safety.

[0196] Online monitoring and data collection:

[0197] A four-channel online Fourier transform infrared spectrometer is deployed at the entrance of the reaction zone to update the concentration spectrum of halogen compounds every 45 seconds.

[0198] Four sets of high-temperature resistant thermocouples are installed in the middle layer of the pyrolysis chamber to ensure uniform temperature distribution with fluctuations not exceeding 3 degrees Celsius.

[0199] The exhaust pipe is equipped with a halogen ion selective electrode to detect the chloride and bromide ion content every second.

[0200] Multivariate optimization model selection strategy:

[0201] Twelve parameters, including halogen compound concentration, temperature, pressure, and airflow rate, are fed into the gradient boosting tree model.

[0202] The optimal catalyst type for output is iron-nickel metal oxide supported on carbon-based activated carbon, with a dosage of 5.8 kg / hour.

[0203] Real-time tuning solutions for machine learning:

[0204] A long short-term memory neural network model was constructed based on 300 pilot-scale tests and 100 industrial-scale tests.

[0205] When the halogen concentration in the exhaust gas exceeds the safety threshold, the system automatically increases the proportion of metal oxides by 8% and returns to the optimal ratio after five minutes.

[0206] Operating parameters and equipment configuration:

[0207] The temperature in the pyrolysis zone was set at 540 degrees Celsius, and the holding time was 55 minutes. The reaction atmosphere was nitrogen with a recycling rate of 88%.

[0208] The reactor's inner wall is coated with ceramic fiber insulation and is equipped with an online dust removal device.

[0209] The exhaust gas is captured in three stages, achieving purification through a combination of cyclone separation, electrostatic adsorption, and activated carbon fine adsorption.

[0210] Dehalogenation and recovery effects:

[0211] The halogen removal rate reached 96.4%, and the dioxin equivalent was reduced to 0.004 ng TEQ per cubic meter.

[0212] Metal recovery rate is 93.7%, and the purity of undecomposed carbon black is approximately 83%, which can be used as an adsorbent material or fuel additive.

[0213] Economic benefits and environmental contributions:

[0214] The cost of processing one ton of waste board has been reduced from 350 yuan to 315 yuan.

[0215] The amount of catalyst used is reduced by 14%, and the processing efficiency is increased by 12%.

[0216] CO2 emissions decreased by 7%, SO2 emissions decreased by 20%, and overall annual benefits increased by 12%.

[0217] Industrial Applications and Improvement Prospects:

[0218] It has been applied in a large electronic waste processing center and has been running stably for three months with a daily processing capacity of 12 tons.

[0219] By adopting a digital factory platform, remote control of emergency plans and automatic generation of reports can be achieved.

[0220] The next phase will introduce online sonar and image monitoring technology to optimize catalyst dispersion and reaction uniformity.

[0221] The above four embodiments are all based on three core technologies: online component monitoring, multivariate optimization models, and machine learning dynamic adjustment. By designing differentiated pretreatment methods and catalyst ratios for waste circuit boards with different component distributions, efficient metal recovery and decomposition of hazardous substances during the pyrolysis process of waste circuit boards are achieved. Embodiment 1 focuses on circuit boards with rich metal content. Through real-time monitoring with infrared spectroscopy and X-ray fluorescence, the ratio of metal-based and carbon-based catalysts is optimized, achieving a metal recovery rate of over 98% and a removal rate of hazardous substances such as dioxins of over 92%. Embodiment 2, for boards with high organic polymer content, introduces online mass spectrometry and a low-temperature plasma-assisted section, enabling the organic matter decomposition rate to reach over 94%, and the concentration of benzene series compounds in the exhaust gas is far below the emission standards. Embodiment 3, in a mixed component scenario, uses a Fourier transform infrared probe and a trace metal analyzer for joint optimization, achieving a metal recovery rate of 96.5% and an organic decomposition rate of 93.8%. Embodiment 4, for high-halogen flame-retardant boards, adds low-temperature plasma pre-dehalogenation and online halogen electrode monitoring, increasing the halogen removal rate to over 96.4% while maintaining ultra-low dioxin emissions. All four cases have achieved refined design in terms of operating temperature, heat preservation time, atmosphere control, exhaust gas purification, and economic benefits. Compared with the traditional quantitative mode, the catalyst dosage is reduced by 10%-14%, the average cost per ton of treatment is reduced by 15%, and the CO2 / NO2 ratio is improved. x Emissions of major pollutants such as SO2 have been significantly reduced, and the technology has been industrialized in several electronic waste treatment plants.

[0222] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An integrated recycling device and pyrolysis catalytic reforming method for circuit boards, characterized in that, include: S1. Physically crush the waste circuit board to obtain pre-treated circuit board fragments and remove their external impurities; S2. The pretreated circuit board fragments are sent into a pyrolysis furnace and pyrolyzed at 300°C to 700°C to decompose the organic matter in the circuit board into gaseous, liquid and solid residues. S3. During the pyrolysis process, the catalyst is injected into the pyrolysis reaction zone; S4. Copper, gold, and silver are extracted from the pyrolysis residue by combining electromagnetic separation and physical separation methods; S5. Harmful gases generated during pyrolysis are recovered, and nitrogen oxides and sulfides are converted into harmless substances by catalytic combustion and condensation. S6. Through an intelligent control system, the pyrolysis process, catalyst injection amount, and metal recovery efficiency are monitored and adjusted in real time.

2. The integrated recycling equipment and pyrolysis catalytic reforming method for circuit boards according to claim 1, characterized in that: The catalyst is a composite catalyst of metal-based and carbon-based materials, and the type and amount of catalyst injected are automatically and intelligently adjusted according to the material composition of the waste circuit boards.

3. The integrated recycling equipment and pyrolysis catalytic reforming method for circuit boards according to claim 2, characterized in that: The catalyst injection step further includes: S3.

1. During the pyrolysis process, the material composition data of the waste circuit boards are collected in real time to calculate the required amount of catalyst to be injected; S3.

2. Based on the compositional distribution of waste circuit boards, establish a multivariate optimization model to select a suitable catalyst type; The catalyst described in S3.3 is dynamically adjusted using a machine learning model, which uses regression analysis to predict the optimal catalyst injection amount.

4. The integrated recycling equipment and pyrolysis catalytic reforming method for circuit boards according to claim 3, characterized in that: The calculation of the amount of catalyst injected is based on: Among them, w i Let c be the mass proportion of the i-th type of component in the waste circuit board. i α is the catalyst demand coefficient corresponding to this component. i denoted as the catalytic efficiency coefficient of the catalyst for this component, and n is the number of types of components in the waste circuit board.

5. The integrated recycling equipment and pyrolysis catalytic reforming method for circuit boards according to claim 4, characterized in that: The model formula for the catalyst type is: Where, β ik w is the catalytic efficiency coefficient between the i-th component and the k-th catalyst. i Let n be the mass proportion of the i-th type of component in the waste circuit board, and n be the number of component types.

6. The integrated recycling equipment and pyrolysis catalytic reforming method for circuit boards according to claim 5, characterized in that: The formula for the optimal catalyst injection amount is: Where, θ i X represents the regression coefficients obtained during model training. i Let n be the input feature of the i-th type of component in the waste circuit board, and n be the number of components.

7. The integrated recycling equipment and pyrolysis catalytic reforming method for circuit boards according to claim 1, characterized in that: The electromagnetic separation step described in S4 uses an electromagnetic separation device to extract magnetic metal particles from the pyrolysis residue. The operating parameters of the electromagnetic separation device are: electromagnetic field frequency of 50kHz to 500kHz and electromagnetic field strength of 1.5 to 3Tesla.

8. The integrated recycling equipment and pyrolysis catalytic reforming method for circuit boards according to claim 7, characterized in that: The physical separation step employs gravity separation, with the following specific parameters: The tilt angle of the sorting tank is 15° to 30°; The flow velocity of the material is 0.5 to 1.5 m / s; Metal particles with a size between 1 mm and 10 mm.

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