CN108031702B - Complete treatment equipment and treatment method for waste circuit board recovery - Google Patents

Abstract

The invention provides a complete set of treatment equipment and a treatment method for waste circuit board recovery, wherein the equipment comprises a pretreatment device, a waste circuit board recovery device and a waste circuit board recovery device, wherein an inlet of the pretreatment device is connected with an outlet of a feeding device and is used for pretreating the waste circuit board from the feeding device or electronic waste containing the waste circuit board; the inlet of the cracking oiling device is connected with the outlet of the pretreatment device and is used for carrying out cracking oiling treatment on the waste circuit board material output by the pretreatment device; the inlet of the crushing/sorting device is connected with the solid material outlet of the cracking oiling device and is used for further crushing and sorting the mixture of the metal and the glass fiber output by the cracking oiling device; and the inlet of the dust removal device is respectively connected with the dust outlets of the pretreatment device and the crushing/sorting device and is used for treating the dust which reaches the standard and is discharged. The equipment has the advantages of good decomposition effect, safety, labor saving, capability of continuously operating for 120 hours, low energy consumption, high productivity, no pollution and capability of reaching the metal recovery rate of 95-98 percent.

Description

Complete set of processing equipment and processing method for recycling waste circuit boards

technical field

The invention relates to a complete set of processing equipment and a processing method for recycling waste circuit boards, especially a complete set of processing equipment and a processing method for harmless waste circuit boards, belonging to the field of non-ferrous metal reproduction.

Background technique

my country is a big producer of electrical and electronic products, but also a big consumer. With the continuous development of the times, the upgrading speed of electrical and electronic products is getting faster and faster, and a large number of electrical and electronic products have entered the peak phase of elimination. According to the statistics of the Ministry of Industry and Information Technology in 2015, more than 200 million electrical and electronic products are scrapped in my country each year, with a weight of more than 5 million tons. Substances or elements contained in waste electrical and electronic products that are harmful to humans, animals, plants and the environment, including lead (Pb), mercury (Hg), cadmium (Cd), hexavalent chromium (Cr ⁶⁺ ), polybrominated biphenyls (PBB ), polybrominated diphenyl ethers (PBDE), polychlorinated biphenyls (PCBs), substances containing ozone-depleting substances, and hazardous wastes regulated by the state. With the blowout generation of electronic waste and the transformation of my country's manufacturing industry towards intelligence and greenness, higher requirements for environmental protection have been put forward. Recycling waste electronic circuit boards has become an urgent social problem that needs to be solved. The board (PCB) recycling market has ushered in a huge opportunity for development.

According to relevant information, the annual compound growth rate of the world's printed circuit board industry is 8.7%, and that of my country is 14.4%. More than 40% of the circuit boards in the world are produced in China, and the Pearl River Delta and the Yangtze River Delta are the concentration places of circuit board manufacturers in my country. Waste circuit boards are a mixture of glass fiber reinforced resin and various metals, plus a large amount of leftovers produced by the production of circuit boards. If not properly disposed of, it will not only cause a large loss of useful resources, but also have a negative impact on the environment. serious hazard. At present, more than 500,000 tons of waste circuit boards need to be processed in China every year, and the market size is more than 18 billion yuan. In the next five years, the compound annual growth rate of waste circuit boards will reach 20%.

As an important component of electronic waste, waste printed circuit boards contain copper, gold, silver and other common metals and rare and precious metals, which have high recycling value; on the other hand, they also contain lead, cadmium, polyvinyl chloride, etc. A variety of heavy metals and harmful substances such as plastics have potential environmental pollution risks. The content of precious metals in waste circuit boards is as high as 40%, and the most is copper. 1 ton of PCB can extract 200-350kg of copper; in addition, 1 ton of waste circuit boards can extract about 300g of gold and 500-2000g of other precious metals. The waste circuit board recycling project is currently a project with relatively high profit potential and wide development space in the renewable resource utilization industry. The average gross profit rate of the industry is about 17%. But at the same time, the recycling technology of waste circuit boards is currently the most difficult treatment process in the treatment of waste electrical and electronic products. In China, most of the small and medium waste circuit board recycling enterprises have backward production technology, and generally adopt brutal methods such as incineration and pickling to recycle high-value metal substances in waste circuit boards. The metal recovery rate is low and the environmental pollution is serious.

At present, enterprises mainly use physical separation technology, pyromelting technology, hydrometallurgy technology and cracking method to deal with waste circuit boards. If the pyromelting technology scheme is adopted, there are problems of high equipment investment, high disposal cost, and is not suitable for small-scale waste circuit board treatment; if the wet smelting technology scheme is adopted, the consumption of chemical reagents is large, a large amount of difficult-to-treat wastewater is produced, and the environment is polluted , suitable for precious metal extraction, not suitable for copper clad circuit board treatment; physical separation technology scheme is adopted, the process is simple, the treatment cost is low, suitable for waste circuit board and copper clad laminate treatment, but it cannot solve the problem of epoxy resin; the pyrolysis method is environmentally friendly, But it can't solve the fiberglass problem.

Contents of the invention

In order to overcome the deficiencies in the prior art, the object of the present invention is to provide a complete set of processing equipment for recycling waste circuit boards. Chemical and harmless treatment not only separates and recycles copper, aluminum, and glass fibers, but also solves the problem of environmental pollution. Another object of the present invention is to provide a treatment method for recycling waste circuit boards, which uses a combination of pyrolysis and physical separation to effectively control costs, ensure environmental friendliness, and achieve harmlessness.

To achieve the above object, the present invention adopts the following technical solutions:

A complete set of processing equipment for recycling waste circuit boards, comprising:

A pretreatment device, the inlet of which is connected to the outlet of the feed device, is used to pretreat the waste circuit boards from the feed device or electronic waste containing waste circuit boards;

A cracking and oiling device, the inlet of which is connected to the outlet of the pretreatment device, and is used for cracking and oiling the waste circuit board material output by the pretreatment device;

A crushing/separating device whose inlet is connected to the solid material outlet of the cracking and oiling device for further crushing and sorting treatment of the metal and glass fiber mixture output by the cracking and oiling device;

The dust removal device, the inlet of which is connected with the dust outlet of the pretreatment device and the crushing/sorting device respectively, is used to process the dust to make the air discharge up to standard.

In the above-mentioned complete set of processing equipment for recycling waste circuit boards, as a preferred embodiment, the pretreatment device includes: a first pretreatment device and/or a second pretreatment device; wherein, the first pretreatment device It includes a tin remover, which is used to separate tin and electronic components from the waste circuit board to obtain a light board circuit board; the second pretreatment device includes a first crusher, a first sorting machine and a manual sorting platform , wherein, the first crusher is used to crush the electronic waste containing waste circuit boards; the first sorter is arranged after the first crusher to crush the crushed materials Sieving and filtering treatment; the manual sorting platform is arranged before or after the first sorting machine, for manually sorting larger materials; preferably, the second pretreatment device also includes: a first magnetic A sorting machine, the first magnetic separator is arranged between the first crusher and the first sorting machine.

In the above complete set of processing equipment for recycling waste circuit boards, as a preferred embodiment, the first crusher is a chain crusher.

In the above-mentioned complete set of processing equipment for recycling waste circuit boards, as a preferred embodiment, the first sorting machine is a corrugated screening tank or a drum screen.

In the above-mentioned complete set of processing equipment for recycling waste circuit boards, as a preferred embodiment, the material processed by the first crusher is a block material smaller than 50mm×50mm; The particle diameter of the crushed material is less than 20mm to 40mm; the manual sorting platform manually sorts out the material larger than 100mm.

In the above-mentioned complete set of processing equipment for recycling waste circuit boards, as a preferred embodiment, the cracking and oiling device includes: a thermal decomposition tank, a catalyst tank, a cooling device, an oil storage tank and a gas burner; wherein, the thermal The inlet of the decomposition tank is connected to the outlet of the pretreatment device; the inlet of the catalyst tank is connected to the gas outlet of the thermal decomposition tank; the inlet of the cooling device is connected to the outlet of the catalyst tank; the oil storage tank The inlet of the gas burner is connected with the oil outlet of the cooling device; the inlet of the gas burner is connected with the gas outlet of the cooling device.

In the above-mentioned complete set of processing equipment for recycling waste circuit boards, as a preferred embodiment, the pyrolysis tank includes a pyrolysis tank, a heating tank and a reversing device, wherein the pyrolysis tank is used to accommodate the The place where the waste circuit board material is described, the heating tank is used to heat the pyrolysis tank to cause cracking reaction to occur in the pyrolysis tank, and the reversing device is arranged outside the heating tank and/or the pyrolysis tank , for reversing the pyrolysis tank and the heating tank, so as to dump out the pyrolyzed material in the pyrolysis tank.

In the above-mentioned complete set of processing equipment for recycling waste circuit boards, as a preferred embodiment, the cooling device is a cooling tower, which is internally provided with a gas cooler, a tower top cooler, and a cooling machine and circulation tank, wherein, The gas cooler and tower top cooler are used to cool the reformed pyrolysis gas, and the cooler and circulation tank are used to recover oil; the gas burner is a combustion furnace.

In the above-mentioned complete set of processing equipment for recycling waste circuit boards, as a preferred embodiment, the crushing/separating device includes: a second crusher, a second sorting machine, and an electrostatic sorting machine; wherein,

The inlet of the second crusher is connected to the solid material outlet of the cracking and oiling device for further pulverizing the metal and glass fiber mixture output by the cracking and oiling device;

The inlet of the second classifier is connected to the outlet of the second crusher for separating heavy and light objects in the materials output by the second crusher;

The inlet of the electrostatic separator is connected to the dust outlet of the second separator for separating glass fiber and metal powder in the dust;

Preferably, the crushing/separating device further includes: a second magnetic separator arranged between the second crusher and the second separator.

In the above complete set of processing equipment for recycling waste circuit boards, as a preferred embodiment, the second crusher is a hammer mill.

In the above-mentioned complete set of processing equipment for recycling waste circuit boards, as a preferred embodiment, the second separator includes an air jig separator and/or an eddy current separator.

In the above-mentioned complete set of processing equipment for recycling waste circuit boards, as a preferred embodiment, the dust removal device includes dust removal equipment, and the inlet of the dust removal equipment is connected to the first crusher and the second crusher respectively. The dust outlet is connected; preferably, the dust removal equipment includes a Z-type sieve, a multi-cone sieve, a cyclone dust collector and a jet filter.

In the above complete set of processing equipment for recycling waste circuit boards, as a preferred embodiment, a belt conveyor is used to transport materials between the machines in the complete set of processing equipment; preferably, the belt conveyor uses a herringbone Type rubber belt, and a protective cover is provided on the belt conveyor.

A processing method for recycling waste circuit boards, comprising the steps of:

Pretreatment step: pretreating different types of waste circuit boards;

Oily cracking step: subjecting the waste circuit board material obtained after the pretreatment step to cracking and oily treatment, and obtain regenerated oil and a mixture of metal and glass fiber after cooling;

Crushing and sorting step: the metal and glass fiber mixture obtained through the oil cracking step is first pulverized, and then sorted to obtain different recycled materials.

The above-mentioned treatment method for recycling waste circuit boards, as a preferred embodiment, the pretreatment step includes a first pretreatment step and/or a second pretreatment step; wherein,

The first pretreatment step is a tin removal step, and the electronic components are separated from the waste circuit board by a tin removal machine to obtain a light board circuit board;

The second pretreatment step includes the following sub-steps: Sub-step 1, crushing the electronic waste containing circuit boards, so as to separate the metal and non-metal in the electronic waste containing circuit boards , breaking up; sub-step 2: sieving and filtering the waste circuit board material obtained in the sub-step 1 to obtain broken materials with a certain particle size; preferably, the crushing process is carried out using a chain crusher; more preferably, Before the sub-step 2 in the second pretreatment step, there are sub-steps of iron removal and manual sorting; further preferably, magnetic separator is used for iron removal, and the material of >100mm is separated by manual sorting selected; furthermore, in the first substep, the electronic waste containing the circuit board can be broken into blocks smaller than 50mm×50mm, and the particle diameter of the broken material obtained after the substep treatment is less than 20mm～40mm .

The above-mentioned treatment method for the recovery of waste circuit boards, as a preferred embodiment, the cracking and oiling step specifically includes the following sub-steps:

The cracking sub-step is to heat the waste circuit board material obtained after the pretreatment step to carry out cracking reaction to obtain pyrolysis gas and a mixture of metal and glass fiber;

In the step of modifying the proton, the pyrolysis gas obtained in the cracking sub-step is modified under the action of a catalyst, that is, the long carbon chain is cut into a short carbon chain;

Cooling sub-step, cooling and liquefying the pyrolysis gas in the proton-modifying step to obtain liquid regenerated oil and waste gas;

Preferably, the heating temperature in the cracking sub-step is 400-600°C, and the pressure is ≤0.05Mpa;

In the cooling sub-step, the light oil and heavy oil in the regenerated oil are recovered independently, and the waste gas is discharged after thermal combustion treatment reaches the standard, and the temperature of the combustion treatment is preferably 250°C-1050°C.

The above-mentioned processing method for recycling waste circuit boards, as a preferred embodiment, the crushing and sorting steps specifically include the following sub-steps:

Pulverizing sub-step, pulverizing the metal and glass fiber mixture produced in the cracking and oiling step;

In the sorting sub-step, first, the materials processed in the crushing sub-step are separated by air-flow jigging and/or eddy current separation to obtain mixed metal products, glass fibers and dust; then the dust is obtained by electrostatic separation Glass fibers and metal powders;

Preferably, the crushing treatment is carried out using a hammer mill;

More preferably, there is an iron removal sub-step before the sorting sub-step;

Further preferably, when adopting airflow jigging separation, if the material after the pulverization sub-step process contains aluminum, red metal, plastics, secondary separation is required.

The above-mentioned processing method for recycling waste circuit boards, as a preferred embodiment, the processing method also includes a dust removal step, and the dust generated in the pretreatment step and the crushing and sorting step is processed by dust removal equipment; more Preferably, the dust generated during the crushing process in the second pretreatment step and the crushing process in the crushing and sorting steps is sent to the dust removal device for dust removal treatment so that it can be discharged up to standard.

The beneficial effects brought by the technical scheme provided by the invention are:

1) The decomposition effect is good: the waste circuit board is produced into heavy oil and light oil, and the recycling of resources is truly realized. The reaction temperature is 500 ° C, and no harmful gases such as dioxin will be produced; at the same time, the recycled oil produced by itself can be used production, reducing operating costs;

3) High safety: the reaction can be stopped urgently by filling nitrogen; some greenhouse gases can be decomposed by secondary combustion;

4) Using a chain crusher to dismantle materials requires 7 to 9 workers, which can replace the original 80 to 100 workers for manual dismantling, greatly improving production efficiency and avoiding workers' exposure to toxic and harmful substances during production;

5) High environmental benefits: no dust pollution during the production process, and no secondary pollution such as waste water and waste gas during the production process;

6) It can run continuously for 120 hours, with low energy consumption and high production capacity;

7) The metal recovery rate is high, the recovery rate can reach 95%-98%, and the metal content in the non-metallic powder is less than 1%. Metals can be directly divided into copper, iron, aluminum, etc., and the purity of metals is as high as 99%, far exceeding the purity of domestic physical separation equipment (more than 80% in China), so as to avoid the mixing of non-metals into metals and cause secondary pollution.

Description of drawings

Fig. 1 is the process flow diagram and the structural representation of the complete set of processing equipment used for the recovery of waste circuit boards in the preferred embodiment of the present invention;

In the figure: 1-Tin removal machine, 3-The first crusher, 4-The first magnetic separator (i.e. 1# magnetic separator), 5-The first separator, 6-Thermolysis tank, 7-Catalyst tank , 8-cooling device, 9-gas burner, 10-second crusher, 11-second magnetic separator (i.e. 2# magnetic separator), 12-second separator, 13-electrostatic separator , 14- dust removal equipment, 15- the first belt conveyor, 16- the second belt conveyor.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention clearer, the following will further describe in detail the embodiments of the present invention in conjunction with the accompanying drawings.

It should be noted that, in the case of no conflict, the features in the specific implementation manners of the present invention can be combined with each other.

In the description of the present invention, the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom" etc. indicate The orientation or positional relationship shown in the drawings is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and does not require that the present invention must be constructed and operated in a specific orientation, so it should not be construed as a limitation of the present invention. In the description of the present invention, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a flexible connection. Detachable connection, or integral connection; it can be mechanical connection or electrical connection; it can be direct connection or indirect connection through an intermediary, and it can be the internal communication of two components. For electricity and communication, it can be a wired connection or a wireless connection. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in specific situations.

The present invention provides a preferred embodiment of a complete set of processing equipment for recycling waste circuit boards, see Figure 1, mainly including a pretreatment device, a cracking and oiling device, a crushing/sorting device, and a dust removal device. The above parts and The connections are explained one by one.

The pretreatment device, the inlet is connected with the outlet of the feeding device, and is used to pretreat the waste circuit boards from the feeding device or electronic waste containing waste circuit boards. Specifically, the pretreatment device includes: a first pretreatment device and/or a second pretreatment device; wherein, the first pretreatment device includes a tin remover 1, and the tin remover 1 is used to pretreat waste circuit boards, namely Tin and electronic components are separated from waste circuit boards to obtain bare circuit boards, which can be directly sent to the cracking and oiling device, and tin and electronic components can be recycled; the second pretreatment device includes the first crusher 3, the first Sorting machine 5 and artificial sorting platform, wherein, the first crusher 3 is used for crushing the electronic waste containing waste and old circuit boards; The first sorting machine 5 is arranged after the first crusher 3, for The materials crushed by a crusher 3 are screened and filtered to facilitate subsequent thermal cracking; the manual sorting platform is arranged before or after the first sorting machine 5 for manually sorting larger materials. Preferably, the second pretreatment device also includes: the first magnetic separator 4 (i.e. the 1# magnetic separator in Fig. 1), the first magnetic separator 4 is arranged on the first crusher 3 and the first separator 5, used to remove magnetic substances such as iron in the material crushed by the first crusher 3. In the pretreatment device in the present invention, the first crusher 3 can be general crushing equipment, but is preferably a chain crusher, which can not only process circuit boards but also directly process small electronic wastes, and can disassemble and break incoming materials. Scatter and crush, and separate the connected wires and plastics; the first sorting machine 5 can be a general sorting device, preferably a corrugated screening tank or a drum screen. Preferably, the material processed by the first crusher 3 is a block material smaller than 50mm×50mm; the particle diameter of the crushed material screened out by the first sorting machine 5 is less than 20mm to 40mm (such as 22mm, 25mm, 28mm, 32mm , 35mm, 38mm), the artificial sorting platform manually sorts out materials larger than 100mm.

The cracking and oiling device, the inlet is connected to the material outlet of the pretreatment device, and is used to process the waste circuit board materials output by the pretreatment device (such as broken materials after sorting or bare circuit boards processed by the tin removal machine 1). Cracking oil treatment to obtain regenerated oil and a mixture of metal and glass fiber. Specifically, the cracking and oiling device comprises: thermal decomposition tank 6, catalyst tank 7, cooling device 8, oil storage tank and gas burner 9, wherein, the inlet of thermal decomposition tank 6 is connected with the outlet of pretreatment device, is used for The waste circuit board material output by the pretreatment device is subjected to thermal cracking treatment to obtain pyrolysis gas and a mixture of metal and glass fiber respectively; the inlet of the catalyst tank 7 is connected to the gas outlet of the pyrolysis tank, and the pyrolysis gas from the pyrolysis tank passes through the catalyst Under the effect of the catalyzer in the groove 7, upgrade (i.e. long carbon chain is cut into short carbon chain); , oil and gas separation after liquefaction; the inlet of the oil storage tank is connected to the oil outlet of the cooling device 8 for reclaiming regenerated oil; the inlet of the gas burner 9 is connected to the gas outlet of the cooling device 8 for the gas discharged from the cooling device 8 Combustion treatment is carried out, and the gas after combustion treatment is discharged up to the standard. In a preferred embodiment of the present invention, the pyrolysis tank 6 includes a pyrolysis tank, a heating tank and an inversion device, wherein the pyrolysis tank is a place for accommodating waste circuit board materials, and the heating tank is used to heat the pyrolysis tank The cracking reaction occurs in the pyrolysis tank, and the inversion device is arranged outside the heating tank and/or the pyrolysis tank for reversing the pyrolysis tank and the heating tank, so that the solid matter after the pyrolysis reaction in the pyrolysis tank Materials such as metal and fiberglass mixtures are poured out. In a preferred embodiment of the present invention, the cooling device 8 is a cooling tower, which is internally provided with a gas cooler, a tower top cooler and a cooling machine and a circulation tank, wherein the gas cooler and the tower top cooler are used for cooling the improved The degraded pyrolysis gas, the cooler and circulation tank are used to recover the oil. In a preferred embodiment of the present invention, the gas burner 9 can be a combustion furnace. The heat source of the heating tank can be regenerated oil recovered by pyrolysis, or natural gas.

Specifically, in the cracking and oiling device of the present invention, the inlet is connected to the material outlet of the second pretreatment device, and is also connected or communicated with the outlet of the first pretreatment device (being the detinning machine 1 in the embodiment of the present invention) , when processing waste and old circuit boards, the bare circuit boards obtained after the waste and old circuit boards are processed by the tin removal machine 1 are transported to the cracking and oiling device from the outlet of the tin removal machine 1. In an embodiment of the present invention, the tin removal machine is about to 1. The bare circuit board obtained is delivered to the pyrolysis tank of the thermal decomposition tank 6, and the above-mentioned thermal cracking process is carried out. When the processed raw material is electronic waste containing waste and old circuit boards, the waste is sorted by the first sorter 5 into the thermal decomposition tank 6 to carry out the above-mentioned thermal cracking treatment.

Crushing/separating device, the inlet is connected to the outlet of the cracking and oiling device, which is used for further crushing and sorting treatment of the metal and glass fiber mixture output from the cracking and oiling device. Specifically, the crushing/separating device includes: a second crusher 10, a second separator 12, and an electrostatic separator 13, wherein the inlet of the second crusher 10 is connected with the outlet of the cracking oilification device for The metal and glass fiber mixture output from the pyrolysis oilification device are further pulverized; the inlet of the second classifier 12 is connected to the outlet of the second crusher 10, and is used to separate the heavy objects in the output of the second crusher 10 ( Such as metals, such as copper, aluminum, stainless steel, etc.) and light objects (such as plastics, such as glass fibers); the inlet of the electrostatic separator 13 is connected with the dust outlet of the second separator 12 for separating the glass in the dust Fiber and metal powder. Preferably, the crushing/separating device also includes: the second magnetic separator 11 (i.e. 2# magnetic separator in Fig. 1), arranged between the second crusher 10 and the second separator 12, for removing iron. Preferably, the second crusher 10 is a hammer mill, and the hammer mill has a better treatment effect than a general crusher; preferably, the second separator 12 includes an airflow jigging separator and/or eddy current separation The airflow jigging separator is based on specific gravity, and the eddy current separator is based on magnetic separation. They can be set at the same time but not started at the same time, but can be selected and used according to the material condition. In a preferred embodiment of the present invention, the crushing/separating device includes: a hammer mill, a second magnetic separator 11, an airflow jigging separator, and an electrostatic separator 13, wherein the hammer mill is connected with the thermal decomposition tank 6 , used to further pulverize the metal and glass fiber mixture from the thermal decomposition tank 6, separate the iron in the pulverized material through the second magnetic separator 11, and then separate the iron in the material through the air jig separator Non-ferrous metals (such as copper, aluminum) and glass fibers are separated, and finally the dust in the airflow jigging separator is introduced into the electrostatic separator 13, and the metal powder and glass fibers are separated by the electrostatic separator 13.

The dust removal device, the inlet is respectively connected with the dust outlet of the pretreatment device and the crushing/sorting device, which is used to treat the dust and make the air discharge up to standard. Specifically, the dust removal device includes a dust removal device 14, and the inlet of the dust removal device 14 is connected with the dust outlets of the first crusher 3 and the second crusher 10 respectively, so as to discharge excess air and dust, reduce the amount of dust, and improve the working environment . In a preferred embodiment of the present invention, the dust removal equipment 14 includes a Z-type sieve, a multi-cone sieve, a cyclone dust collector and a jet filter, and a Z-type sieve, a multi-cone sieve, and a cyclone dust collector are used to separate For particulate dust, jet filters are used for final dust removal.

Preferably, belt conveyors are used to transport materials between the machines in the above-mentioned complete set of processing equipment. In the preferred embodiment of the present invention, in order to avoid material slipping when the material is climbing up, the belt conveyor uses a herringbone rubber belt; in order to avoid the entry of foreign objects, the belt conveyor is also subjected to closed treatment, that is, a closed buffer treatment is set Devices, for example, with protective covers on belt conveyors.

The present invention also provides a processing method for recycling waste circuit boards, comprising the following steps:

Pretreatment step: pretreating different types of waste circuit boards;

Oil cracking step: the pretreated PCB waste is subjected to cracking and oil treatment, and after cooling, regenerated oil and a mixture of metal and glass fiber are obtained;

Crushing and sorting steps: the metal and glass fiber mixture obtained through the oil cracking step is first pulverized and then sorted to obtain different recycled materials.

In the above-mentioned treatment method for recycling waste circuit boards, as a preferred embodiment, the pretreatment step includes a first pretreatment step and/or a second pretreatment step; wherein,

The first pretreatment step is the detinning step, that is, the tin and electronic components are separated from the waste circuit board through the detinning machine, wherein tin and electronic components (heavy metals such as tin, lead, nickel, etc. are basically in the electronic components) are removed and recycled, Leaving the bare circuit board can directly enter the cracking and oiling step for cracking and oiling treatment;

The second pretreatment step includes the following sub-steps: sub-step 1, crushing the electronic waste containing circuit boards, so that metals such as iron and non-metals such as plastics in the electronic waste containing circuit boards are separated , breaking up; sub-step two: screening and filtering the waste circuit boards obtained in sub-step one to obtain broken materials of a certain particle size; preferably, the crushing process is carried out using a chain crusher. Preferably, there are sub-steps of iron removal sub-step and manual sorting before sub-step 2 in the second pretreatment step. More preferably, magnetic separator is used to remove iron, and the material >100mm is sorted out by means of manual sorting. Further preferably, in the sub-step 1, the electronic waste containing the circuit board can be broken into blocks smaller than 50mm×50mm, and after the sieving and filtering in the sub-step 2, the particle diameter of the broken material is less than 20mm-40mm (such as 22mm , 25mm, 28mm, 32mm, 35mm, 38mm).

In the above-mentioned treatment method for recycling waste circuit boards, as a preferred embodiment, the cracking and oiling step specifically includes the following sub-steps:

The pyrolysis sub-step is to heat the PCB waste obtained after pretreatment to carry out the pyrolysis reaction to obtain pyrolysis gas and a mixture of metal and glass fiber;

In the proton modification step, the pyrolysis gas obtained in the cracking sub-step is modified under the action of a catalyst, that is, the long carbon chain is cut into a short carbon chain;

In the cooling sub-step, the pyrolysis gas in the proton modification step is cooled and liquefied to obtain liquid regenerated oil and waste gas.

In the above-mentioned treatment method for recycling waste circuit boards, as a preferred embodiment, in the cracking and oiling step, the heating temperature in the cracking sub-step is 400-600°C (such as 410°C, 420°C, 450°C, 480°C, 520°C, 550°C, 580°C, 590°C)°C, pressure ≤0.05Mpa. The cracking step is to heat the PCB waste under the condition of isolating the air, control the temperature and pressure, so that the organic matter in the PCB waste is decomposed and converted into oil and gas, which can be recycled after being condensed and collected. The cracking sub-step is carried out under anaerobic conditions, so the production of dioxins and furans can be suppressed, the amount of waste gas produced is small, and the environmental pollution is small.

In the above-mentioned treatment method for recycling waste circuit boards, as a preferred embodiment, in the cooling sub-step, after the oil/gas separation, wherein the light oil and heavy oil in the regenerated oil are recovered independently, and the waste gas is treated by thermal combustion after reaching the standard emission. The uncooled tail gas (i.e. exhaust gas) produced during the oil recovery process mainly includes methane, ethane, ethylene, propane, propylene, butene, butane, etc., and is discharged after being burned by a gas burner. The temperature of the burner is 250°C -1050°C.

In the above-mentioned processing method for recycling waste circuit boards, as a preferred embodiment, the crushing and sorting steps specifically include the following sub-steps:

The pulverization sub-step is to pulverize the metal and glass fiber mixture produced in the cracking and oiling step; preferably, the pulverization treatment is carried out with a hammer mill, and the different ductility characteristics of different metals are used to knead them into types Metal balls of different sizes.

Sorting sub-step, at first the materials processed by the crushing sub-step are separated by air flow jigging and/or eddy current separation to obtain mixed metal products (such as copper, aluminum, stainless steel), glass fiber and dust respectively; then dust Glass fiber and metal powder (such as copper powder) are obtained respectively by electrostatic separation. The glass fiber is separated from the metal through two sorting steps, and the metal part is sorted out to improve the metal recovery rate. At the same time, the glass fiber can be sold again, which is conducive to the effective utilization of resources. More preferably, there is also an iron removal sub-step before the sorting sub-step. More preferably, when air-flow jigging is adopted, if the material processed by the pulverizing sub-step contains aluminum, red metal (mainly refers to copper, also has a small amount of zinc, gold, silver and other precious metals), plastics, need Perform secondary sorting.

In the above treatment method for recycling waste circuit boards, as a preferred embodiment, the treatment method also includes a dust removal step, and the dust generated in the pretreatment step, crushing and sorting steps is treated by dust removal equipment; more preferably, the second The dust generated during the chain crushing in the pretreatment step and the crushing process in the crushing and sorting steps are all sent to the dust removal device for dust removal treatment and then discharged up to the standard. The dust content of the discharged gas is preferably as low as 10mg/ ^m3 .

The above method is completed by the complete set of processing equipment of the present invention. The complete set of processing equipment and processing method for recycling waste circuit boards and the processing method for recycling waste circuit boards of the present invention will be described below in conjunction with the embodiments.

Example

The complete set of processing equipment for the recycling of waste and old circuit boards provided by this preferred embodiment, the structure is as shown in Figure 1, and the equipment mainly includes the following devices: tin remover, magnetic separator, chain crusher, corrugated screening tank, Thermal decomposition tank, catalyst tank, cooling device, oil storage tank, gas burner (specifically combustion furnace), hammer mill, airflow jigging separator, electrostatic separator, belt conveyor; the above devices are commercially available products, as follows:

1) 2 belt conveyors. It is used to convey the PCB materials placed at each machine. The length of the conveyor is 6000mm. In order to avoid the material from falling when the discharge climbs, a herringbone black rubber belt is used. The horizontal elevation angle of the fuselage is 25 degrees, and the fuselage material is made of 20 steel materials , The foot column material is square tube, the head wheel is magnetic head wheel, the belt linear speed is 4455mm/min, and the power supply is AC3Φ×380V×50Hz deceleration motor drive, the processing capacity is above 5000kg/hr.

2) One desoldering machine.

3) There are 3 belt magnetic separators, the length and width of the magnet discs are not less than 750*900mm, and the magnetic field strength cannot be lower than 4000 Gauss. The frame material is made of No. 20 steel material, the belt width is 700mm, and the belt material is double-sided rubber material covering the reinforced core.

4) One chain crusher. The rotor chain crusher equipped with a powerful airflow screening function is used to crush waste circuit boards into small pieces. The electronic circuit board produces shearing action, which can break the waste electronic circuit board into pieces smaller than 50mm×50mm.

5) One corrugated screening tank.

6) Cracking and oiling unit.

Pyrolysis tank: including one pyrolysis tank, one heating tank and one decomposition tank inversion device; the diameter and height of the reaction tank of the pyrolysis tank are 800×2138mm, the material is 304 stainless steel, and the effective capacity is 4.5m ³ ; The furnace diameter and height of the heating tank are 600×3250mm, the material is SS400+ refractory insulation material, and the oil combustion heating system is adopted; the length, width and height of the decomposition tank reversing device are 3400×3800×5500mm, the material is SS440, and it is reversed at 120°C. Waste plastics, etc. put into the thermal decomposition tank of the equipment are heated and decomposed and gasified.

Catalyst tank: 1 catalyst tank, the diameter and height of the reactor are 770×885mm, the material is 304 stainless steel, and the capacity is 0.35m ³ . Under the action of the catalyst in the catalyst tank, the pyrolysis gas is modified (long carbon chains are cut into short carbon chains).

Cooling device: 1 cooling tower with a length, width and height of 1400×31000×2275mm. Circulating water temperature 20°C; 1 gas cooler with a diameter and height of 712×2900mm, made of 304 stainless steel and SS440, using oil spray gas cooling method; 1 tower cooler with a diameter and height of 500×2500mm, made of 304 stainless steel, SS440, cooling capacity 46500 kcal/H; cooling machine and circulation tank, length, width and height 900×1250×850mm, material is 304 stainless steel, capacity is 0.75m ³ . Cooling is carried out in the cooler, liquefied, and recycled oil is recovered. Cooling recovery is divided into two parts, that is, light oil and heavy oil are recovered independently.

One frame for oiling device, made of SS400 (anti-rust).

7) One hammer mill: to further crush the solid material discharged from the pyrolysis oilification device, that is, the mixture of metal and glass fiber. Utilize the different ductility properties of different metals to knead them into metal balls of different types and sizes.

8) One airflow jigging separator. The air jig separator can separate heavy objects (such as metal) and light objects (such as plastics) according to the weight of the material and the difference in particle composition. The material moves upward along the inclined jig plane. The ventilator blows air in the opposite direction of material movement, so that light materials cannot maintain upward movement and exit from the bottom of the air jig separator, and only heavy materials will exit from the top. The air jig separator can separate two kinds of materials each time. If the mixed material contains such as aluminum, red metal, plastic, secondary separation is required. In the first sorting, heavy metals and light plastics can be sorted out. During secondary separation, relatively heavy red metal and relatively light aluminum can be separated out.

9) One electrostatic separator: it is mainly used to separate a small amount of metal in the dust output by the airflow jig separator. The main working principle is a method to achieve re-separation by utilizing the difference in electrical properties of each component in a solid material in a high-voltage electric field.

10) 1 set of dust removal device: the chain crusher will generate dust during the crushing process; in addition, during the hammer mill process, fresh air is continuously input into the hammer mill, and the air flow is used to cool the hammer mill and its outlet. material, and can extract the fine material and lint produced in the feeding or hammer milling process. Dust of different weights and different particles is separated by the cyclone dust collector. The remaining air is piped to the jet filter for final dust removal. It can ensure that the dust content of the discharged gas is as low as 10mg/m ³ .

Referring to Fig. 1, the connection relationship of the above-mentioned devices is:

The outlet of the feeding device (not shown in the figure) is connected with the inlet of the tin remover 1; the light board circuit board outlet of the tin remover 1 is connected with the inlet of the thermal decomposition tank 6;

The outlet of the feeding device (not shown in the figure) is connected with the entrance of the chain crusher through the first belt conveyor 15; the outlet of the chain crusher is connected with the entrance of the first magnetic separator 4; the first magnetic separator The outlet of 4 links to each other with the inlet of corrugated screening tank; the outlet of corrugated screening tank links to each other with the entrance of thermal decomposition tank 6 through the second belt conveyor 16; The second belt conveyor 16 is provided with manual sorting platform;

The thermal decomposition tank 6, the catalyst tank 7, and the cooling device 8 in the cracking oilification device are connected successively; wherein, the solid outlet of the thermal decomposition tank 6 is connected with the entrance of the hammer mill, and the gas outlet of the thermal decomposition tank 6 is connected with the outlet of the catalyst tank 7. The inlet is connected; the outlet of the catalyst tank 7 is connected with the inlet of the cooling device 8; the waste gas outlet of the cooling device 8 is connected with the inlet of the gas burner 9, and the liquid outlet of the cooling device 8 is connected with the oil storage tank;

In the sorting device, the inlet of the hammer mill is connected to the solid outlet of the thermal decomposition tank, and the outlet of the hammer mill is connected to the inlet of the second magnetic separator 11; the outlet of the second magnetic separator 11 is connected to the airflow jigging separator The inlet of 12 is connected; the dust outlet of airflow jig separator 12 is connected with the inlet of electrostatic separator 13;

In addition, the dust outlet of the chain crusher 3 is connected to the inlet of the dust removal device 14; the dust outlet of the hammer mill is connected to the inlet of the dust removal device 14.

The above-mentioned complete set of processing equipment is used to disassemble and recycle waste and old cables. The process includes: a pretreatment step (comprising detinning; and/or, crushing-magnetic separation-screening); an oily cracking step (cracking- catalytic reforming - gas cooling - oil/gas separation - gas combustion); crushing and sorting steps (crushing - magnetic separation - sorting); and dedusting steps. details as follows:

1) Detinning. The electronic components are separated from the waste circuit board by using the tin remover 1 to obtain the electronic components, tin and light board circuit board respectively. Heavy metals such as tin, lead, and nickel in waste circuit boards are basically contained in electronic components. After the electronic components are removed, the waste circuit boards basically do not contain heavy metals. For complete circuit boards and circuit board leftovers, directly enter the thermal decomposition tank 6 after de-tinning, that is, enter the next process-cracking process, so that the separation rate can be improved.

2) Broken-magnetic separation-screening. First, the electronic waste containing circuit boards (such as scrapped laptops) is sent to the chain crusher for chain crushing, and the iron, plastic and larger electronic components attached to the electronic waste are broken up. The rotor chain crusher with powerful airflow screening function can be used to crush waste electronic circuit boards into pieces smaller than 50mm×50mm; then, the materials >100mm are manually sorted out; then, the first magnetic separation After the machine 4 magnetically separates and removes iron, it is screened by the corrugated screening tank 5, and the crushed materials with a particle diameter of less than 20mm are screened and sent to the thermal decomposition tank 6, which enters the next process—the cracking process. The crushing-magnetic separation-screening step in the present invention is in order to make the subsequent cracking of material more thorough, improve cracking efficiency.

3) cracking. Carry out in the pyrolysis tank 6, specifically, put the waste circuit board material obtained through step 1) or 2) into the pyrolysis tank, use nitrogen to replace the air in the pyrolysis tank, and put the pyrolysis tank into the heating tank , external heating is carried out through the heating tank. After the temperature in the pyrolysis tank reaches 500 ° C, the plastic (such as epoxy resin) contained in the waste circuit board material will be thermally decomposed and gasified. Move out, change to the next tank, and continue production.

4) Catalytic reforming. The decomposition gas generated in the pyrolysis tank is sent to the catalyst tank, and the silica catalyst is used for catalytic reforming to modify it into short carbon chains (long carbon chains are cut off).

5) Gas cooling. Including gas cooler, tower top cooler. The oil and gas produced by catalytic upgrading is liquefied in the cooling device 8, and the pump circulation is adopted, and the oil mist gas cooling method and the multi-tube water cooling method are used, and the temperature of the circulating water is below 20 °C.

6) Oil/gas separation. Regarding oil recovery, in the cooling machine and circulation tank, the oil cooler is used to recover oil, and the pump circulates the oil to the oil storage tank, in which light oil and heavy oil are recovered independently. The uncooled tail gas produced in the oil recovery process mainly includes methane, ethane, ethylene, propane, propylene, butene, butane, etc., which are discharged up to the standard after being burned in the combustion furnace. The temperature of the combustion furnace is 250°C-1050°C. The plastic consumption of the pyrolysis tank in the oil cracking device is 100kg, and the temperature in the pyrolysis tank is 500°C; the quality of oil produced after cracking is 51.10kg, which is 51.1% of the plastic mass; the gas density of liquefied petroleum gas is 2.35kg/ Nm ³ , the calorific value of liquefied petroleum gas is 44750Kj/m ³ . After the plastic is decomposed, the residual substance is 41.0% of the plastic mass, and the non-condensable gas accounts for 7.9% of the total plastic mass.

7) Crushing-magnetic separation-sorting. The metal and glass fiber mixture produced in step 3) is sent to the hammer mill 10 for further pulverization, and in the hammer mill, the blades rotating at high speed further crush the small pieces of material to obtain fine particles with a particle size less than 2mm Materials, using different metals with different ductility characteristics, knead them into metal balls of different types and sizes; then pass through the third magnetic separator 11 to screen the iron metal; Metals (copper, aluminum, stainless steel), glass fibers, and dust are separated; finally, other metal powders are further separated from the dust by an electrostatic separator 13, and finally the glass fibers are left.

8) Dust removal and other environmental protection measures. It mainly deals with waste gas, waste water, solid waste and noise. Waste water and noise are generated continuously; for noise, pollution is reduced through vibration reduction and sound insulation; for waste water, domestic sewage is discharged into the sewage pipe network after pretreatment in septic tanks. The waste gas produced by pyrolysis is mainly discharged through the combustion furnace after reaching the standard, that is, the waste gas (non-condensable gas) during the cracking process of waste circuit boards is about 1.42% of the mass of waste circuit boards, and the waste gas (non-condensable gas) is burned through the combustion furnace to produce H ₂ O and CO ₂ are discharged through the chimney, which basically does not produce exhaust gas pollution. As for solid waste, the separated ones are sold to the outside world, and the refractory residues are sold to relevant recycling units. Regarding the dust, through the dust removal device, the dust of different weights and different particles is separated through the Z-type sieve, the multi-cone sieve, and the cyclone dust collector, and then the final dust removal is carried out through the filter. The filter can ensure the dust content of the discharged gas. as low as 10mg/m ³ .

In the present embodiment, the power of the complete production line is 775KW, and the annual production of iron 800t, non-ferrous metals 3200t (containing about 10 tons of precious metals such as gold and silver), and oil 1500t can be processed for waste and old circuit boards. The crushing production line in the pretreatment device (executing step 2) crushing-magnetic separation-screening production line): the annual normal operation hours are greater than 7000 hours; the crushing production line is normally continuous for no less than 120 hours, and the output is 2-3t/h (pretreatment Completed circuit boards), the theoretical maximum production capacity of the equipment is 15,000t/year (preprocessed circuit boards); the metal separation efficiency is greater than 98%.

The complete set of treatment process provided by the present invention is to send the circuit board into the thermal decomposition tank of the oil cracking device for cracking reaction by crushing, screening and sorting the circuit board to obtain small particle materials, or the bare circuit board obtained after detinning. Part of the raw material is thermally decomposed and gasified, leaving a mixture of metal and glass fiber; on the one hand, the decomposition gas generated in the thermal decomposition tank is sent to the catalyst tank for catalytic reforming and reforming into short carbon chain substances, and then the modified oil and gas are Liquefied to obtain cooling oil recovery, the uncondensed tail gas generated during the oil recovery process is burned in the combustion furnace to meet the standard discharge; on the other hand, the metal and glass fiber mixture is further pulverized through a hammer mill, and finally passed through the airflow jigging The sorting device is used for sorting, so that copper, aluminum, stainless steel and glass fiber are completely separated and recycled, and the metal powder and glass fiber are further separated and recycled through electrostatic sorting. Adopting the complete treatment process provided by the present invention has high recovery efficiency, good decomposition effect, environmental protection and no pollution.

Due to the complexity of PCB materials, the separation of copper, aluminum and glass fibers is difficult to complete. The parameters in the above-mentioned complete set of processing equipment, that is, the processing method, can be adjusted according to the calculation results of actual operating conditions. Therefore, without violating the scope of the appended claims of the present invention Under the premise, in the specific implementation process, some appropriate changes can be made to the selection of key parameters in the present invention. The invention is especially suitable for the crushing, cracking and sorting of waste circuit boards.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of the present invention. within the scope of protection.

Claims (9)

1. A complete set of treatment equipment for waste circuit board recovery, characterized in that, the equipment includes:

the inlet of the pretreatment device is connected with the outlet of the feeding device and is used for pretreating the waste circuit board from the feeding device or the electronic waste containing the waste circuit board;

the pretreatment device comprises: the first pretreatment device and/or the second pretreatment device; wherein,

the first pretreatment device comprises a tin removing machine which is used for removing tin and electronic elements from the waste circuit board to obtain a light panel circuit board;

the second pretreatment device comprises a first crusher, a first sorting machine and a manual sorting platform, wherein the first crusher is used for crushing the electronic waste containing the waste circuit board; the first separator is arranged behind the first crusher and is used for screening and filtering crushed materials; the manual sorting platform is arranged in front of or behind the first sorting machine and used for manually sorting out larger materials;

the second preprocessing unit further includes: the first magnetic separator is arranged between the first crusher and the first separator; the first crusher is a chain crusher; the first separator is a corrugated screening groove or a rotary screen; the material processed by the first crusher is lump material with the size less than 50mm multiplied by 50 mm; the particle diameter of the crushed material screened by the first separator is less than 20-40 mm; the manual sorting platform is used for manually sorting materials larger than 100 mm;

the inlet of the cracking oiling device is connected with the outlet of the pretreatment device and is used for carrying out cracking oiling treatment on the waste circuit board material output by the pretreatment device;

the pyrolysis oiling device comprises: the device comprises a thermal decomposition tank, a catalyst tank, a cooling device, an oil storage tank and a gas burner; wherein the inlet of the thermal decomposition tank is connected with the outlet of the pretreatment device; the inlet of the catalyst tank is connected with the gas outlet of the thermal decomposition tank; the inlet of the cooling device is connected with the outlet of the catalyst groove; the inlet of the oil storage tank is connected with the oil outlet of the cooling device; the inlet of the gas burner is connected with the gas outlet of the cooling device;

the thermal decomposition tank comprises a pyrolysis tank, a heating tank and a reversing device, wherein the pyrolysis tank is a place for containing the waste circuit board materials, the heating tank is used for heating the pyrolysis tank to enable cracking reaction to occur in the pyrolysis tank, and the reversing device is arranged outside the heating tank and/or the pyrolysis tank and is used for reversing the pyrolysis tank and the heating tank so as to pour out the materials pyrolyzed in the pyrolysis tank;

the cooling device is a cooling tower, and a gas cooler, a tower top cooler and a cooler and circulating tank are arranged in the cooling tower, wherein the gas cooler and the tower top cooler are used for cooling the modified pyrolysis gas, and the cooler and circulating tank is used for recovering oil; the gas burner is a combustion furnace;

when the waste circuit board is treated, the light board circuit board obtained after the waste circuit board is treated by the detinning machine is conveyed to a pyrolysis oiling device from an outlet of the detinning machine; when the electronic waste containing the waste circuit board is treated, the materials of the electronic waste sorted by the first sorting machine enter the thermal decomposition tank to be subjected to heating and cracking treatment;

the inlet of the crushing/sorting device is connected with the solid material outlet of the cracking oiling device and is used for further crushing and sorting the mixture of the metal and the glass fiber output by the cracking oiling device;

the crushing/sorting apparatus includes: a second crusher, a second classifier, an electrostatic classifier; wherein,

the inlet of the second crusher is connected with the solid material outlet of the cracking oiling device and is used for further crushing the mixture of the metal and the glass fiber output by the cracking oiling device; the second crusher is a hammer mill;

the inlet of the second separator is connected with the outlet of the second crusher and is used for separating heavy objects and light objects in the materials output by the second crusher; the second separator comprises an air flow jigging separator and/or an eddy current separator;

the inlet of the electrostatic separator is connected with the dust outlet of the second separator and is used for separating glass fibers and metal powder in dust;

the crushing/sorting apparatus further comprises: the second magnetic separator is arranged between the second crusher and the second separator;

the inlet of the dust removal device is respectively connected with the dust outlets of the pretreatment device and the crushing/sorting device and is used for processing dust so that the air is discharged after reaching the standard;

the dust removing device comprises dust removing equipment, and an inlet of the dust removing equipment is respectively connected with dust outlets of the first crusher and the second crusher; the dust removing equipment comprises a Z-shaped sieve, a multi-cone sieve, a cyclone dust remover and an air-jet filter.

2. The plant for recycling waste circuit boards as claimed in claim 1, wherein a belt conveyor is used for conveying materials between the machines in the plant.

3. The plant for recycling waste circuit boards as claimed in claim 2, wherein the belt conveyor uses a herringbone rubber belt, and a protective cover is arranged on the belt conveyor.

4. A processing method for waste circuit board recovery, which is implemented by using the complete processing equipment for waste circuit board recovery of any one of claims 1-3, and comprises the following steps:

a pretreatment step: pretreating different types of waste circuit boards;

an oil cracking step: carrying out cracking oiling treatment on the waste circuit board material obtained after the pretreatment step, and cooling to obtain regenerated oil and a mixture of metal and glass fiber;

crushing and sorting: and crushing the mixture of the metal and the glass fiber obtained in the oil cracking step, and then sorting to obtain different recycled materials respectively.

5. The processing method for recycling the waste circuit boards as claimed in claim 4, wherein the pretreatment step comprises a first pretreatment step and/or a second pretreatment step; wherein,

the first pretreatment step is a detinning step, and the electronic element is separated from the waste circuit board through a detinning machine to obtain a light panel circuit board;

the second preprocessing step includes the following substeps: the method comprises the following steps that firstly, electronic waste containing a circuit board is crushed, so that metal and nonmetal in the electronic waste containing the circuit board can be split and scattered; and a second substep: screening and filtering the waste circuit board material obtained in the first substep to obtain a crushed material with a certain particle size; the crushing treatment is carried out by adopting a chain crusher; a second substep in the second pretreatment step is also preceded by a substep of removing iron and a substep of manually sorting; removing iron by using a magnetic separator, and sorting out materials with the thickness of more than 100mm in a manual sorting mode; in the first substep, the electronic waste containing the circuit board can be crushed into blocks smaller than 50mm multiplied by 50mm, and the particle diameter of the crushed material obtained after the processing of the substep is smaller than 20 mm-40 mm.

6. The processing method for recycling waste circuit boards as claimed in claim 4 or 5, wherein the cracking and oiling step comprises the following substeps:

a cracking sub-step, namely heating the waste circuit board material obtained after the pretreatment step for cracking reaction to obtain pyrolysis gas and a mixture of metal and glass fiber;

a modification substep, namely modifying the pyrolysis gas obtained in the cracking substep under the action of a catalyst, namely cutting long carbon chains into short carbon chains;

and a cooling substep, wherein the pyrolysis gas after the modification substep is subjected to cooling liquefaction treatment to obtain liquid regenerated oil and waste gas.

7. The processing method for recycling waste circuit boards according to claim 6,

the heating temperature in the cracking sub-step is 400-600 ℃, and the pressure is less than or equal to 0.05Mpa;

in the cooling substep, light oil and heavy oil in the reclaimed oil are independently recovered, the waste gas is discharged after reaching the standard through hot combustion treatment, and the temperature of the combustion treatment is 250-1050 ℃.

8. The processing method for recycling waste circuit boards as claimed in claim 7, wherein the crushing and sorting step comprises the following substeps:

a crushing substep, crushing the mixture of the metal and the glass fiber produced in the cracking oiling step;

a separation substep, namely firstly subjecting the materials treated in the crushing substep to air flow jigging separation and/or eddy current separation to respectively obtain mixed metal products, glass fibers and dust; then the glass fiber and the metal powder are respectively obtained from the dust through electrostatic separation;

the crushing treatment is carried out by adopting a hammer mill;

the sorting substep is also preceded by a deironing substep;

when the air jigging separation is adopted, secondary separation is needed if the materials processed by the crushing substep contain aluminum, red metal and plastic.

9. The processing method for recycling waste circuit boards as claimed in claim 8, further comprising a dust removal step of processing dust generated in the pretreatment step and the pulverization and sorting step by a dust removal device; and when the second pretreatment step is used for crushing treatment, and the crushing and sorting steps are used for crushing treatment, the generated dust is sent to the dust removal device for dust removal treatment, so that the dust is discharged after reaching the standard.

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