« Back to Home Page

Sign up for the 3p daily dispatch:

Recycling used gadgets by saving the memory of their plastic shapes

| Wednesday October 22nd, 2008 | 0 Comments

circuit-board-mouse-pad.jpgRecycling gadgets is a headache. Many of the few gadgets that actually are kept out of the landfill are painstakingly taken apart in the Third World under hazardous conditions and creating environmental problems. A new method called Active Disassembly using Smart Materials could be the problem that producers and consumers are looking for.
Product disassembly offers an attractive alternative to manual methods for reducing the landfill and helping countries to get on the legal targets they at the moment fail to achieve. That’s because the method optimizes the recovery of hazardous and valuable components during the recycling process.
David Harrison and Habib Hussein, two scholars who investigated ADSM, claim that by inserting fasteners within the materials of the gadgets, a solution might be at hand. At the end of a product’s life the fasteners can be heated directly, which causes the device case to fall apart without screws having to be undone or stiff clasps opened manually. “This is one important design feature that might make recycling electronic devices with plastic cases much easier”, the two scholars believe. They researched the method at the School of Engineering and Design at Brunel University, UK and have set up a dedicated website (ActiveDisassembly.com) to the issue.


Their concept relies on the so-called shape memory effect in engineering plastics, or polymers. Plastics can be fabricated in one shape – the unfastened state – and then moulded a second time into a new shape – the fastened state. When the fastened state version is heated, the plastic will revert to its original, unfastened state, as it retains a molecular memory of the form in which it was originally produced.
The two scholars are looking to get funding from European countries. Europe’s Waste Electrical and Electronic Equipment (WEEE) directive, aimed at reducing electrical and electronic goods going to the landfill, provides incentives to design equipment that is more recyclable. The recycling problem of e-waste is also a big problem in the US. Sources estimate that between 50 and 80% of the 300,000 to 400,000 tons of electronics collected for recycling in the U.S. ends up in mostly Third World countries like China, India and Nigeria.
The standard practice for disassembling them is the use of hammers, gas burners and manual labor to strip them down to the bare metals, glass and other valuable recyclables. A recent study by Greenpeace reveals that India generated 1040 tonnes of e-waste every day last year from discarded Computers, Televisions and Mobile Phones. The ewaste floods are projected to grow over 15% to more than double the waste heaps by 2012.
At present, merely 3% of the e-waste reaches authorized recyclers while remaining lands in informal recycling yard causing threat to environment and public health. The study presents the position of major electronics manufacturers on IPR (Individual Producer Responsibility), and their application on the ground through takeback services offered in India.
“It seems like e-waste takeback in India is in no way a priority for global brands; otherwise, how can one explain the irresponsible conduct of brands like Sony, Sony Ericsson, Toshiba, Samsung and Philips, which have no take-back service in India whatsoever?” questioned Abhishek Pratap, Greenpeace Toxics campaigner and the principal investigator for this study.
“Allowing valuable components and metals to be recovered more efficiently from the millions of devices discarded every year,” says Hussein. The researchers have developed a case-fastening device based on one such shape memory polymer. Their tests demonstrated that lowering the device at end of life into hot water, leads to the fasteners reverting to their unfastened state and the case falling apart, on agitation. They have also shown that the fasteners retain their integrity for at least two years without disassembling spontaneously.
One thing the two have going for them and their ideas is that the European Union targets to recycle technical equipment through improving the recovery of hazardous and valuable components during the recycling process. What’s necessary is to create the fastenings and tabs of gadgets based on the shape-memory effect of the plastics used to produce the devices, so that disassembling them can be automated.


▼▼▼      0 Comments     ▼▼▼

Newsletter Signup