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New Technique for Recycling PCBs 77

Posted by samzenpus
from the use-and-use-again dept.
MattSparkes writes "PCBs from discarded computers, cellphones and other devices could be recycled less harmfully using a technique developed by researchers in China. Unlike current methods, it can be used to reclaim metals such as copper without releasing toxic fumes into the air. Only a small numbers of PCBs are currently recycled."
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New Technique for Recycling PCBs

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  • Bulding materials? (Score:5, Interesting)

    by TubeSteak (669689) on Thursday March 01, 2007 @02:35AM (#18191668) Journal
    They want to compact & use the non-metallic parts as building materials.

    This raises the question: Will there still be toxins in these compacted objects? And will they come out when the structure is eventually demolished?

    Even concrete has all kinds of nasty that leeches out when you turn it into a pile of rubble.
    • Re: (Score:1, Informative)

      by dido (9125)

      The plastic used for most PCB's is polyvinyl chloride, which in itself isn't particularly toxic under most circumstances. It's in common use these days for plumbing fixtures and the like, as well as for PCB's. However, if you burn PVC plastic, it gets converted into some particularly nasty dioxins and furans which are dangerously carcinogenic.

      • Re: (Score:2, Interesting)

        by PC-PHIX (888080) *

        However, if you burn PVC plastic, it gets converted into some particularly nasty dioxins and furans which are dangerously carcinogenic.

        Thus, if you happen to be inside one of these buildings when they catch fire, you are really screwed!

      • I read an article in Harper's Magazine about a bunch of people living in a garbage dump in the Philippines. The kids gather all the computers into a pile and then light it on fire. They stand around the fire and poke it so everything plastic burns. Then they gather the metal components and sell them. And if that isn't bad enough, the garbage sometimes falls over and kills 200 people living in garbage huts underneath!
        • by digitalchinky (650880) <dtchky@gmail.com> on Thursday March 01, 2007 @06:52AM (#18192588)
          In the Philippines they really only burn insulated wire, car tyres, and anything with springs like beds and chairs. Electronics rarely make it to the dump sites these days, too much value to be thrown away, they usually end up in repair shops, stripped for spares. (I do a lot of work for a charity here on Smokey Mountain dump site in Manila)

          You are right about the garbage falls, though it's usually the land slides that take out 200 people or more at a time.

          • Re: (Score:2, Informative)

            Here is the article:

            http://harpers.org/TheMagicMountain.html [harpers.org]

            It's a fascinating look at the underworld of the Garbage Dwellers. It's really sad, horrible, horripilating, and awful.

            The author says a recent garbagefall killed hundreds of people. And you're right: the people burn insulation off wires. Which still produces dioxins and carcinogens.

            An excerpt:

            Wandering from pile to pile, calling out, "Piyesa! Piyesa!" (Parts! Parts!), are brokers of electronic and computer components, a new and lucrative category
      • by ajs318 (655362) <sd_resp2@@@earthshod...co...uk> on Thursday March 01, 2007 @04:03AM (#18191946)

        The plastic used for most PCB's is polyvinyl chloride
        No it isn't. PCBs are made either from glass fibre (FR4) or resin-bonded fabric (CEM1). PVC would soften too much at soldering temperatures.
        • by dido (9125) <didoNO@SPAMimperium.ph> on Thursday March 01, 2007 @04:41AM (#18192062)

          Right, now that I've looked it up, but the issues are still the same it would seem. Burning these types of boards to get at the metal is still something that you really don't want to do. They typically use brominated flame retardants [wikipedia.org] on these boards, which while they are generally inert and non-poisonous in their normal state, when burned they also produce deadly carcinogenic fumes, especially in the presence of copper [haloclean.com]. That makes that ingenious technique described in the article all the more useful: it separates the metallic and non-metallic components without burning.

          • Re: (Score:3, Interesting)

            by ajs318 (655362)
            Well, the whole point is they're designed not to burn! Under fault conditions, electronic apparatus usually overheats; and the last thing you want it bursting into flames. PCB board, when it gets hot, generally just tends to smoulder a bit and cut off its own air supply. Usually, it's the overheating component that fails first; and once it goes open-circuit, the heat source is removed and the unpleasant fumes stop.
      • Pasta PCB (Score:3, Interesting)

        by iangoldby (552781)
        This reminds me of a story I heard about printing circuits on a sheet of pasta.

        Pasta PCB [sciencemuseum.org.uk]

        Once the protective coating is removed, the board quickly biodegrades, and the ICs and metal coatings can be easily reclaimed.

        And here's a Pretty pasta picture [bbc.co.uk]
    • by dmayle (200765)

      Eeeeeek!

      I repeat, Eeeeeek!

      All those lovely cancer causing fumes, sure we don't release them because we turn them into building materiel.

      But... What happens when your neighbor's house built of this stuff catches fire? Sure, it's not something that happens often on the time scale of an individual, but when you consider the number of buildings as a whole, buildings burning down happens pretty damn often...

      • by smithmc (451373) *

          But... What happens when your neighbor's house built of this stuff catches fire? Sure, it's not something that happens often on the time scale of an individual, but when you consider the number of buildings as a whole, buildings burning down happens pretty damn often...

        Not nearly as often as PCs get thrown into landfills...

  • That's better. (Score:5, Interesting)

    by Fantastic Lad (198284) on Thursday March 01, 2007 @03:15AM (#18191796)
    I was getting tired of all the fear-mongering with regard to China. It's nice to see the editors pull up something positive about our neighbors to the East.


    -FL

    • Re: (Score:3, Funny)

      by couchslug (175151)
      "I was getting tired of all the fear-mongering with regard to China."

      The copper reclaimed from the circuit boards is being machined into shaped charge projectiles by the Sino-Jihadist Internationale, a shadowy Islamo-Maoist group. Just when we thought the Yellow Peril had receded, it reappears in a slightly browner incarnation.
      • by couchslug (175151)
        Wait, come back! I'd like to hear from whoever modded this "Flamebait" which part of the joke they didn't get. I don't care about the moderation, but WTF?
  • by Anonymous Coward
    someone recycling PHB's. Preferably into something useful.
  • Recycling (Score:2, Interesting)

    by wvmarle (1070040)
    Only a small numbers of PCBs are currently recycled.
    Large quantities are being shipped to China for stripping of components and recovery of the copper. Especially now the copper price is so high. So I don't believe just a small number is being recycled - in the USA maybe, but not world wide!

    Wouter.
    • Re: (Score:1, Informative)

      by Anonymous Coward
      Actually there are regulation in China that prevents old PCB from being imported into China on fear of China being dumping ground. Getting China set up as repair depot was (is?) a headache because of that.

      Also China is following EU into having their own RoHS program effectively banning PCB made with toxic metals which most older PCB contains.

      On the other hand, this would still help China in recycling PCB that is already there.
      • Re: (Score:3, Informative)

        by lxt518052 (720422)
        I think the Chinese government's concern is not unjustified.

        http://www.chinadaily.com.cn/english/doc/2005-05/ 2 4/content_445129.htm [chinadaily.com.cn]

        Hi-tech waste being smuggled into China has caused big pollution because the method used to recycle them. Recycling is a generally good thing, but not so if the process actually causes harm to the local residents.

        I think those waste exporters in developed countries are rather selfish in moving the problem to China and India, although it comes at no surprise to me in that th

        • People who dislike China tend to mention Tiananmen Square a lot, but they always forget the Tank Man is also a Chinese.

          Some who like China also talk of Tiananmen Square [wikipedia.org], as well as how 2 million Nationists Chinese led by Chiang Kai-shek [wikipedia.org] invaded and subjegated 20 million on the island called Formosa [wikipedia.org], meaning "beautiful island", by the Portuguese but now called Taiwan. After the invasion Formosans had their own version of the Holocaust, 28 February 1947 [taiwandc.org], which led to the massive slaughter of thousands of

          • by lxt518052 (720422)
            Get your facts straight first if you want convince people you actually know what you're talking about.

            The population of Taiwan IS about 23 million at the moment, minus 2 million mainland immigrants - that's 1 million. Are you saying after 60 some years since Japan handed back Taiwan to Chiang's government after WWII, the net population growth is only 1 million?

            If the KMT government was so bad as to cause the population stop growing, how come its economy took off and became one of the Asian Dragons, toget

            • Get your facts straight first if you want convince people you actually know what you're talking about.

              I did not provide any facts I didn't include a link to where I got the data.

              The population of Taiwan IS about 23 million at the moment, minus 2 million mainland immigrants - that's 1 million. Are you saying after 60 some years since Japan handed back Taiwan to Chiang's government after WWII, the net population growth is only 1 million?

              Secondly, nowhere did I give any numbers other than "thousands" o

    • Large quantities are being shipped to China for stripping of components and recovery of the copper. Especially now the copper price is so high. So I don't believe just a small number is being recycled - in the USA maybe, but not world wide!

      Another thing that needs to be recycled more are cellphones. Many electronics gadgets, especially cellphones [bbc.co.uk], use coltan [wikipedia.org], and mining of coltan is fueling the conflict or fighting and war along with the dissemination of gorillas in the Congo. That new movie out about

  • PCBs - You mean printed circuit boards? It'd also be nice if we could recycle polychlorinated biphenyls (or if the Linux kernel could recycle process control blocks).
    • It would be nice if we could just keep polychlorinated biphenyls out of the environment in the first place.
    • I dont think printed circuit boards should be allowed to use the acronym PCB, its way too confusing. I just circulated this article to about 20 different experts and journals thinking they were talking about poly-chlorinated bi-phenyls.

      What?! I read slashdot, did you really expect me to RFA?!?!
  • Prediction (Score:4, Insightful)

    by Anonymous Coward on Thursday March 01, 2007 @03:55AM (#18191918)

    We will be mining the landfills as soon as it becomes economically feasible. I think this will happen within a decade or so. They're full of tons of stuff we threw away before extracting all of the usefulness. It's metal-rich sludge full of useful organic matter to power the nanodigesters (or whatever we have to invent).

    Not that you shouldn't recycle your aluminum and steel cans today.

    • I have been saying this exact same thing for a few years. There is so much useful material that we have thrown away and at such high concentrations that this should seem like a logical, and profitable, step in the cleanup of our planet.
      • Re:Prediction (Score:4, Insightful)

        by Muad'Dave (255648) on Thursday March 01, 2007 @08:52AM (#18193294) Homepage
        Me too, but most with regard to all of the barely used nuclear fuel rods languishing at reactors all over the country. There's a ton of energy left in them, and by burning up the actinides you're left with waste that's 'hot' for a faction of the time. From this Wikipedia article [wikipedia.org]:

        Compared to current light-water reactors with a once-through fuel cycle that uses less than 1% of the energy in the uranium, the IFR has a very efficient (99.5% usage) fuel cycle.
        and

        Another important benefit of removing the long half-life transuranics from the waste cycle is that the remaining waste becomes a much shorter-term hazard. After the actinides and transuranics are removed from the spent fuel, the remaining waste elements have half lives of a few decades at most. The result is that within 300 years, such wastes are no more radioactive than the ores of natural radioactive elements.

        This interview [nationalcenter.org] with George S. Stanford, Ph.D highlights the history and potential on IFR's.

        • Me too, but most with regard to all of the barely used nuclear fuel rods languishing at reactors all over the country. There's a ton of energy left in them, and by burning up the actinides you're left with waste that's 'hot' for a faction of the time.

          IEEE's magazine "Spectrum" has a good article on this, dealing with France's Nuclear Wasteland [ieee.org] . The article also points out the problems with reprocessing.

          Falcon

    • is not a good idea if the toxic waste has already polluted soil and underground water system.

  • by throwaway18 (521472) on Thursday March 01, 2007 @04:41AM (#18192064) Journal
    I'm currently trying to make sense of the WEEE regulations. UK businesses that supply electronic products are required to register with a waste collection and recycling scheme by the 15th of march if they fall into vaguely defined categories covering most consumer products and some other stuff. A few months after that suppliers have to start taking back unwanted electronics.

    The intention is the push the costs of disposal back to the manufacturer.
    A director of a UK manufacturing company told me recently that the extra costs for him amount to 18% of turnover for no practical benefit.

    It seems to be a full employment scheme for lawyers and beaurocrats. After reading lots of conflicting information on the web I tried reading the act of parliament that implements the European directive and was even more confused and outraged afterwards.
    I'm sure there are lots of cases where people can argue over whether their product falss into the vaguely defined categories.

    This is on top of CE marking, EMC, and ROHS. I'v seen companys discontinue products because it is just not worth the cost of redesigning to not use lead solder and other non-rohs stuff. With WEEE on top niche market electronics manufacturers just took a big hit.
    Consideirng how easy it is to buy very very cheap, non-CE marked electronics direct from Hong Kong via ebay I worry about whats left of UK electronics manufacturing. It's been decimated by pacific rim competition over the last ten years already.
    • Re: (Score:3, Insightful)

      by Detritus (11846)
      A director of a UK manufacturing company told me recently that the extra costs for him amount to 18% of turnover for no practical benefit.

      No practical benefit? I'd think that proper disposal and recycling of his company's products is a practical benefit for society-at-large. It might even encourage the company to design products with a lower total life-cycle cost.

    • by squizzar (1031726)
      Another side effect of this is that people don't seem to want to give stuff away any more. I'm not sure if its WEEE, but there's some bit of legislation about waste disposal that means my University will not give away old computers and parts. I'd like to see them given away to students (particularly those for whom a reasonably good computer is hard to afford), or maybe given to local schools etc. Or even reused in different departments - most of the uni computing facilities are nowhere near as good as th
      • by Firethorn (177587)
        Talk about violating the idea of saving the enviroment...

        My training:
        Reduce - If you don't need to use 2 gallons, don't. If possible, use a friendlier substance over an unfriendly one. IE soap & water rather than a petrol based cleaner
        Reuse - If it's still good, keep using it. Use reusable parts when possible rather than disposables
        Recycle - After the first two have been done, if possible, recycle the items rather than simply throwing them away.
  • I think that while finding new ways to recycle old computer parts and PCBs is still a good idea, educating the public about how and where to take their old computer parts is probably money equally well spent. I know that I have often just tossed old computer cards and whatnot that I would have preferrably recycled, for a simple lack of knowledge as to where to take them.
  • Sure, we can mash up some circuit boards and make something. Burning them is silly. I would rather smoke crack than PVC.
    • Sure, we can mash up some circuit boards and make something. Burning them is silly.

      Tell that to the poor people that are doing just that. http://cities.expressindia.com/fullstory.php?newsi d=81450 [expressindia.com] I saw a documentary about it a few years ago, people melting/burning PCBs for the copper/gold/whatever metal they can get their hands on. I saw women and kids burning old computer boards, they didn't seem to care that they were hovering right above the flames, inhaling the thick black smoke. I wish I could find

      • Follow up (Score:4, Informative)

        by Emetophobe (878584) on Thursday March 01, 2007 @06:02AM (#18192372)
        I happened to find a good story with a few pictures. http://www.ban.org/Library/ghosts_in.html [ban.org]

        Here's a choice quote:

        Every year Guiyu takes in more than a million tonnes of computer waste, earning its residents, according to mainland press reports, RMB1 billion. All day, every day, mountains of wire and other equipment are burned in Guiyu's streets to obtain copper and other scrap metals. Printed circuit boards are heated over charcoal burners to liberate them of computer chips that might be reusable. The boards are then soaked in acid to extract gold, and the waste dumped alongside or in the nearby Lianjiang River. Printer cartridges are ripped apart for their toner and recyclable aluminium, steel and plastic parts. Cathode-ray tubes are hammered open for their copper yokes.

        The result is that the air, land and water on which local people depend have all been poisoned. Local well water is already undrinkable, even after boiling, and fresh supplies must be trucked in from the town of Chan Dim 15 kilometres away. According to the report: "It is extremely likely that due to the presence of PVC or brominated flame retardants in wire insulation, the emissions and ashes from such burning will contain high levels of both brominated and chlorinated dioxins and furans - two of the most deadly persistent organic pollutants. It is also highly likely that cancer-causing polycyclic aromatic hydrocarbons are present in the emissions and ash."

        "Compared to the rest of China, this place has more miscarriages," says Doctor Li Fai-ping, who works in the maternity ward at the local Chao Yang Yiu Fai Hospital. "Babies simply die in the wombs. There are several cases a month." She adds that the Government has done nothing to assess the damage being done by the e-waste industry. "No scientists have come here to test the effects [of the pollution on the community]. We are sent to work here, we are scared too." "The fact that nobody knows of the dangers is the most depressing thing," says BAN researcher Jim Puckett, co-author of the report.
        • The result is that the air, land and water on which local people depend have all been poisoned. Local well water is already undrinkable, even after boiling, and fresh supplies must be trucked in from the town of Chan Dim 15 kilometres away.

          I think the mention of boiling as a method of purifying the water shows the unfortunate region's ignorance about the materials they're "processing". It makes me think that some poor bunch of folks got sick from the contamination, reported the illnesses to officials, and

  • Why not feed the waste into a high-temperature furnace, like those used to rip apart toxic chemical compounds into more benign elements and compounds?
    • by lxt518052 (720422)
      From TFA:

      Only a small numbers of PCBs are recycled. They are typically put into copper smelters, which risks releasing harmful toxic fumes. Most circuit boards are simply incinerated or thrown into landfill, which releases toxic pollutants such as heavy metals and dioxins into groundwater and the atmosphere.

      They're already using the method you suggested and it has problems. Plus, high-temperature furnace has rather large carbon footprint, which in turn accelerates global warming.

      • by Detritus (11846)
        I'm not a chemical engineer, but I believe the furnaces used for neutralizing toxic materials run at substantially higher temperatures that the typical metal smelter.
        • Re: (Score:3, Informative)

          by lxt518052 (720422)
          Sure, but to generate the heat needed to sustain such high furnace temperature you've got to burn a large amount of fossil fuel. Note the carbon footprint I mentioned.

          Also, heavy metals are not consumed by burning. Think about the pollution when it's escaped into the atomosphere.

          With all these cost and danger, what have we gain from it? Not much is recycled. We just add tons of greenhouse gas to the planet.

    • by Ogive17 (691899)
      You mean something like this http://www.polyurethane.org/s_api/sec.asp?CID=867& DID=3520 [polyurethane.org]?

      I saw this on TV a few nights ago. Not exactly benign, but useful.
  • It would be great to extract the metals and save the plastic with tracings, then we can make computer cases, notepad covers, desk veneers, and other office supplies out of it.
  • PHBs? (Score:2, Funny)

    by srealm (157581)
    I first read that as 'Recycling PHBs' ... now that is something I would REALLY like to see, because lord knows I need a new boss!
  • The Chinese university method does not seem particularly new, and not particularly good for the environment. It seems to involve very intensive shredding and pulverizing processes, using an enormous amount of energy, to mechanically convert circuit boards into particles so minute that metal and non-metal, tightly bonded together in the board, can be separated by further mechanical processing. The production of pure metals using such processes is, in laboratory settings, theoretically possible, but it woul
    • "This is an interesting technique that can be a part of a portfolio of technologies to treat PCBs,"

      It didn't say this is THE environment friendly way to treat PCBs. But combined with other methods, it could prove more effective. Note this is only research, not meant to be all-encompass solution.

      Your argument about the Chinese energy infrastructure is valid though. The reality is China has large coal reserve but not a lot of oil. Now researches are being done to turn coal into oil. I hope development in

  • I thought it said "New Technique for Recycling PHBs".
  • It's no mystery that circuit boards are produced by soldering the pieces together. If the parts can be soldered they can certainly be de-soldered as well. Instead of smashing the pieces, why not just slowly heat the boards to the point at which the solder liquifies and then vibrate them to free up the pieces. If the boards could tolerate the heat during production then obviously they can tolerate the same heat in dissassembly without burning.

    Once the various capacitors, chips, connectors and such are separa

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