CN2904572Y

CN2904572Y - Device for separating different material layers of printed circuitboard in supercritical fluid

Info

Publication number: CN2904572Y
Application number: CNU2006200720592U
Authority: CN
Inventors: 刘志峰; 潘君齐; 宋守许; 刘光复; 王淑旺
Original assignee: Hefei University of Technology
Current assignee: Hefei University of Technology; Hefei Polytechnic University
Priority date: 2006-04-01
Filing date: 2006-04-01
Publication date: 2007-05-23
Anticipated expiration: 2016-04-01

Abstract

Printing circuit board different material layer separation device in supercritical fluid, which is characterized in that a closed heating container is arranged, form a automatic temperature control electric heating element and temperature sensor is arranged is arranged in the close cavity of the heating container; a independent high temperature high pressure reaction vessel is arranged in closed cavity of the heating container; the high temperature high pressure reaction vessel is connected with CO2 air source through air booster pump, and is communicated with water source through liquid measuring pump; A return pipe is arranged in the high temperature high pressure reaction vessel, the return pipe sequentially goes through a cooler, a filter, a drier and a condenser; and is connected with air collection vessel through air-fluid booster pump. The utility model method has advantages of good economy, high recovery rate, good recovery environment, little energy consumption; the utility model device has advantages of simple structure, and easy implementation.

Description

The device that printed circuit board different material layer separates in supercritical fluid

Technical field:

The utility model relates to the layering retracting device of printed substrate.

Background technology:

Along with the high speed development of information industry, wiring board production is the gesture of sharp increase.The average annual growth rate of world's circuit board industrial is 8.7%.Till 2003, China has become second largest in the world printed substrate producing country, 1,000,000 square metres of annual productions 60.74, and 54.88 hundred million dollars of the output values, and to surpass 20% speed increment every year on average.Show that according to State Statistics Bureau's survey data in 2003 China will eliminate about 1,500 ten thousand waste household appliances current every year.By 2004, China had 5,000,000 computers, up to ten million mobile phones to enter the phase of eliminating approximately in every year.In all these waste electronic electric equipment products, contain a considerable amount of printed substrates.Add to produce about 24% leftover bits in the wiring board manufacture process, need the abandoned printed circuit board total number of recycling surprising.

Printed substrate has insulated substrate, prints conductive layer on insulated substrate, and electronic devices and components are installed.The base material of normal employing is that the papery that has the glass reinforced epoxy of brominated flame retardant or add fire retardant is strengthened phenolic resins.Conductive layer is generally metallic copper, and other metallic element for example nickel, silver, tin, tin-lead and gold etc. also is used as anticorrosive or senior conductive metal and uses.About 95% value can be recycled in the printed substrate.Metal content in the wiring board is equivalent to tens of metal content in the common mineral to positions up to a hundred, and the content of metal is up to 40%, and the rich ore tenor of occurring in nature only 3～5%.The development of printed substrate manufacturing process develops into multilayer (reaching as high as 58 layers according to the data introduction) from individual layer, bilayer on the structure rapidly, higher integrated level, and material use kind is more and more, has more strengthened recovery difficult.Printed substrate not only contains a considerable amount of precious metals (gold, silver, palladium and platinum) and base metal (copper, iron, nickel and tin), and contains the heavy metal element to the toxic effect of environment such as lead, mercury, antimony, cadmium, chromium and beryllium.Unsuitable recycling may cause serious environmental to be polluted to these noxious substances.With respect to other the other parts of municipal refuse and discarded electronic product, the environmental hazard of printed substrate is bigger.Simultaneously, owing to contain the bromination fire retardant in the base material, the conventional burning or the meeting of incineration produce carcinogenic teratogenesis mutagenic matter hexichol bioxin and dibenzofuran, and health is had harm.

The printed substrate recovery and treatment method mainly contains mechanical approach, method of chemical treatment, burning or pyrolysismethod at present.Wherein, mechanical approach is through preliminary treatment, fragmentation, sorting, finally obtains the dusty material enriched substance, carries out subsequent processes again.The key of mechanical approach high efficiente callback is to guarantee that the wiring board material monomer fully dissociates.Can produce the dust that contains glass fibre and resin in a large number because waste printed circuit board is formed in complexity, the shattering process, distribute toxic gas, continuous crushing also can cause heating, and for monomer dissociation brings a difficult problem, for this reason, Germany has begun to adopt the cryogenic freezing crushing technology.Also have in shattering process, to add the current cooling and remove dust, but cause the waste and the pollution of water resources.Method of chemical treatment is also referred to as wet method, is to handle with the method for pickling or corrosion, by the chemical solvent generation chemical reaction extraction metallic element of metal level and adding.Chemical method cost recovery height, if deal with improperly also and can cause serious pollution to water resources, therefore commercial Application is subjected to a certain degree limiting.Burning or pyrolysismethod are heating line plates under the environment of aerobic or anaerobic, produce the product with certain recycle value.Burning or pyrolysismethod hold decrement to subtracting of wiring board and have certain effect, and a part will be valuable, the wasting of resources of volatile components but burning will cause, and also will cause the discharging of poisonous and harmful substance such as hexichol bioxin and dibenzofuran.In above-mentioned three kinds of methods, chemical process is simple, but less economical and be easy to generate secondary pollution; Incineration method resource recovery is low; Pyrolysismethod environmental performance difference can't large-scale promotion application.Mechanical approach is better in aspect effects such as economy, environment and organic efficiencies than preceding two kinds of methods, and at present a lot of countries all launch research and carried out industrial applications this technology.But because mechanical approach derives from the mine metallurgical technology, along with the continuous use of new and high technology and new material in the wiring board manufacturing, the mechanical approach that technical development falls behind relatively has been difficult to be fit to handle new printed substrate.Be mainly reflected in: organic efficiency is low, can only reclaim 75% of metal material, can't reclaim other and strengthen packing material; Deficiency in economic performance, because it is low to reclaim metal purity, subsequent treatment expense height is so overall economic efficiency is low; Environmental pollution is serious, and it is huge to recycle the process energy resource consumption simultaneously.

Summary of the invention:

The utility model is for avoiding above-mentioned existing in prior technology weak point, the device that a kind of economy is better, the rate of recovery is high, recovery environment printed circuit board different material layer good, that energy resource consumption is little separates in supercritical fluid being provided

The utility model adopts following technical scheme for the technical solution problem:

Design feature of the present utility model is that airtight heating container is set, and in the airtight cavity volume that electrothermal device that the formation temperature is controlled automatically and temperature sensor are arranged on heating container, in the airtight cavity volume of described heating container, the independent setting has CO ₂The high-temperature high-pressure reaction kettle of supercritical fluid environment, described high-temperature high-pressure reaction kettle are respectively by gas-gas inflator and CO ₂Source of the gas is communicated with, and is communicated with the water source by microprocessor pump drive; In described high-temperature high-pressure reaction kettle return duct is set, described return duct is successively through subcooler, filter, drier and condenser, and is connected with the gas collecting tank by the gas-liquid pressure-boosting pump.

Processed printed substrate is placed the supercritical fluid environment of reactor, lose cementation, strengthen basic unit and conductive layers apart, collect basic unit, conductive layer after separating respectively until the printed substrate tack coat, and the bonding layer material after separating.

Bonding layer material in the printed substrate is the resin material that has added curing agent and curing accelerator, that wherein the most frequently used is FR-4, epoxy resin commonly used is the A type, generates bisphenol A diglycidyl ether (DGEBA) with A (DPP) with epoxychloropropane (ECH) reaction by bis-phenol.Belong to this epoxy resin more than 85% in the epoxy resin that uses at present.In fact DGEBA is not single pure compound, but a kind of mixture of polymolecular amount, its general formula is as follows:

After handling through the utility model device, the strand of bonding layer material is opened, and generates small-molecule substance as C ₆H ₅OH, C ₆H ₄BrOH and C ₆H ₃Br ₂OH loses its adhesive property.

Supercritical fluid (Supercritical fluid SCF) is that temperature and pressure is in the fluid on critical temperature and the critical pressure.The utility model device is that printed substrate is reclaimed in layering in the supercritical fluid environment.Compared with prior art, have following remarkable beneficial effect:

1, higher resource recovery, metal conducting layer and insulated substrate are directly left with stratiform in the printed substrate, reclaim the purity height, simultaneously for utilizing the nonmetallic materials in the wiring board that possibility is provided.

2, higher recovery economy: each after the separation layer keeps original-shape, simplified subsequent recovery technology, increased the recovery Industrial economic benefit, can promote high-tech to reclaim the development of industry.

3, good environmental performance: employed carbon dioxide and water all are eco-friendly materials in the processing procedure, and can recycle.

4, reduce energy resource consumption: compare with using more Mechanical Crushing and thermal cracking recovery technology, the energy resource consumption of the utility model method is littler.

Description of drawings:

Accompanying drawing is the utility model structural representation.

Number in the figure: 1 source of the gas pipe, 2 gas bombs, 3 heating containers, 4 reactors, 5 temperature sensors, 6 electrothermal devices, 7 water source jars, 8 measuring pumps, 9 air outlet valves, 10 coolers, 11 filters, 12 driers, 13 gas collecting tanks, 14 condensers, 15 air outlet valves, 16 gas-liquid pressure-boosting pumps, 17 air compressors, 18 Pressure gauges, 19 gas-gas inflators, 20 return ducts

Below by embodiment the utility model is further described:

Embodiment:

Referring to accompanying drawing, airtight heating container 3 is set, in the airtight cavity volume that temperature sensor 5 that the formation temperature is controlled automatically and electrothermal device 6 are arranged on heating container 3, in the airtight cavity volume of heating container 3, the independent setting has CO ₂The high-temperature high-pressure reaction kettle 4 of supercritical fluid environment, high-temperature high-pressure reaction kettle 4 are respectively by gas-gas inflator 19 and CO ₂Source of the gas pipe 1 and gas bomb 2 are communicated with, and are communicated with water source jar 7 by measuring pump 8.

Shown in the figure, return duct 20 is set in high-temperature high-pressure reaction kettle 4, return duct 20 passes through water cooler 10, filter 11, drier 12 and condenser 14 successively, at this moment the CO of HTHP ₂Condensation of gas becomes liquid, returns in the gas collecting tank 13 by gas-liquid pressure-boosting pump 16 again, is convenient to reclaim repeatedly use.After reclaiming fully, open air outlet valve 15, make that the pressure in the high-temperature high-pressure reaction kettle 4 is reduced to atmospheric pressure, compressor 17 provides power source to calm the anger.

In concrete the enforcement, should temperature and pressure be set routinely and control automatically, comprise pressure gauge sensor 18 is set, with the automatic control of realization response container design temperature and setting pressure, the relative set display unit is used for showing and monitor system parameters.

Processed printed substrate is placed the supercritical fluid environment of reactor, lose cementation until the printed substrate tack coat, basic unit and conductive layers apart are collected basic unit, conductive layer after separating respectively, and the bonding layer material after separating.

In concrete the enforcement, supercritical fluid is CO in the reactor ₂, reactor temperature is set to 150 ℃-300 ℃, and pressure is 15MPa-50MPa, and the reaction time is 1 hour-10 hours, and specifically can be set to reactor temperature and be 235 ℃, pressure is 35MPa, the reaction time is 3 hours.

Supercritical fluid also can be CO in the reactor ₂With the mixture of water, the volume of water is no more than 20% of reactor volume., specifically be set to 7%.

Claims

1, the device that in supercritical fluid, separates of printed circuit board different material layer, it is characterized in that being provided with airtight heating container (3), the electrothermal device (6) and the temperature sensor (5) of control are arranged in the airtight cavity volume of heating container (3) automatically to constitute temperature, in the airtight cavity volume of described heating container (3), the independent setting has CO ₂The high-temperature high-pressure reaction kettle of supercritical fluid environment (4), described high-temperature high-pressure reaction kettle (4) are respectively by gas-gas inflator (19) and CO ₂Source of the gas is communicated with, and is communicated with the water source by microprocessor pump drive (8); Return duct (20) is set in described high-temperature high-pressure reaction kettle (4), described return duct (20) is successively through subcooler (10), filter (11), drier (12) and condenser (14), and is connected with gas collecting tank (13) by gas-liquid pressure-boosting pump (16).

2, the device that in supercritical fluid, separates of printed circuit board different material layer according to claim 1, it is characterized in that being provided with reactor temperature is 150 ℃-300 ℃, pressure is 15MPa-50Mpa.

3, the device that separates in supercritical fluid of printed circuit board different material layer according to claim 1 is characterized in that being provided with 235 ℃ of reactor temperatures, pressure is 35MPa.