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The US tackles e-waste, while the EU clamps down on WEEE processing

The US is taking on some serious issues associated with e-waste. Many states have taken on the idea of preventing e-waste from entering landfill sites- a somewhat belated idea, leaving them lagging way behind the rest of the world.

The US is taking on some serious issues associated with e-waste. Many states have taken on the idea of preventing e-waste from entering landfill sites- a somewhat belated idea, leaving them lagging way behind the rest of the world. The Vermont House of Representatives passed S.77, An Act Relating to the Disposal of Electronic Waste. The bill bans the disposal in landfills of computers and other electronic devices that contain toxins, and it establishes a convenient, free way for consumers to recycle them. Some twenty states have passed similar legislation and manufacturers have implemented such programs.

However, in the EU, such issues, which have already been addressed, are throwing up further teething troubles, with recyclers throughout Europe comming under fire for poor processing techniques. These predominantly fall into the area of material extraction from such wastes as computers, laptops and goods containing chips and processors. Electrical conductivity and bus speeds rely on the use of Gold, platinum and silver. These precious materials are simply being amalgamated through large reprocessors employing large shredders, which only seperate out ferrous metals. The remainder end up being wasted, along with the precious metals. Management of WEEE consists of three steps: collection, pre-processing and end-processing, with each step typically carried out by specialised operators. Using substance flow analysis (SFA), a method which tracks the movement of substances through a process, this study investigated the pre-processing stage: that is the pre- sorting, separation through manual dismantling and/or shredding, and further manual and/or mechanical separation of waste into different material categories that are then sold to the end-processing stage.

The SFA demonstrated that after the pre-processing stage, only about a quarter of the gold and palladium and a tenth of the silver that could potentially be recovered ends up in output streams from which they will actually be recovered. This implies that process operators lose the revenue for nearly three-quarters of the gold and palladium contained in the WEEE input.

Unselective fine shredding in the pre-processing stage disperses precious metals amongst other materials causing unwanted losses. For example, about 5 per cent of palladium ends up in filter dust because palladium is often found in the ceramics of circuit boards and is broken down to dust during shredding.

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