Friday, July 26, 2013

UK streets paved in precious metals?

One of the country’s biggest street cleaning firms has announced it is to “mine” the sweepings it collects from roads and pavements, in search of gold and other precious metals.

Veolia Environmental Services believes it can find at least £1 million worth of materials like platinum, palladium and rhodium from the muck swept up from Britain’s streets each year. These metals are commonly used in catalytic converters and tiny amounts can be thrown out by car exhausts, which then settle on street surfaces. The company believes it may even find traces of gold and silver in the sweepings, as tiny fragments can rub off clothes, shoes and jewellery. Until now, street sweepings have been sent straight to landfill or compost sites, but Veolia has now established the country’s first plant to extract precious metals from the material, at Ling Hall, near Rugby, Warwickshire.
Richard Kirkman, technical director, said: “In the past we have always sent our street sweeping to landfill or compost sites. We are separating everything out with flotation tanks and mechanical sorting machines. We are left with this fine black dust that contains palladium, rhodium and platinum at levels found when it is mined from the ground.”

Veolia has contracts to sweep streets in around 40 towns and cities around the country and collects up to 165,000 tons of sweepings a year. The company estimates that up to 1.5 tons of platinum, 1.3 tons of palladium, and 0.8 tons of rhodium can be recovered.