One city’s trash is Veolia’s gold (or at least platinum)

Tue, 2015-05-05 08:47 -- Kevin Ebi


If you want gold or other precious metals, you have to go mining for them, right? Actually, they’re probably already sitting right atop your city’s streets -- perhaps millions of dollars worth.

With every street a veritable gold mine, Council Associate Partner Veolia is panning for gold on British streets.  And the waste recovery leader figures it could find £1 million worth of gold and other precious metals in a year. And that’s in the United Kingdom alone.

As absurd as it may seem, there’s some precedent for Veolia’s efforts. A New York man makes more than $800 a week selling gold and diamond dust that he finds in the cracks of the city’s streets and sidewalks. Veolia’s system is more high tech and can find many more types of valuable minerals.

Sweeping up money
Veolia is finding the valuables as it sweeps the streets. The sweepers pick up street dust, which is sent to a special facility for analysis and sorting. Similar to a gold-panning operation, Veolia’s system combines a washing and floating process with sieves and conveyors.

Regular recyclables, like bottles and aluminum cans, are pulled aside for traditional recycling. Stones and pebbles are recycled too; they’re sent off to be used in building and landscaping projects.

The dust that’s left is further sorted. It typically contains trace amounts of platinum, rhodium and palladium, valuable minerals that are extracted and reused as well. Over the past year, it found £100,000 worth of precious metals on British streets and that was with just a single processing center. It now plans to open two more.

More minerals are deposited all the time
The minerals on the street are replenished as fast as Veolia can sweep them up. They are not dropped accidentally by people; they are emitted by cars. Platinum, rhodium and palladium are used in the catalytic converters of cars to help filter poisonous emissions. But tiny fragments of those minerals break off and do come out of the tailpipe.

A Forbes analysis finds in a metric ton of street dust, there’s likely 4-tenths of a gram of platinum, a similar amount of palladium and a tenth of a gram of rhodium. It may not sound like much, but even those trace amounts are worth about $70.

But it’s not about the money
While the money grabs headlines, Veolia started the project because of the environment. The minerals aren’t just valuable -- they’re also toxic. Street sweeping is critical to preventing more of those materials from running off into the water. But it also wanted to prevent them from ending up in landfills too.

By pulling the toxic minerals out, the remaining dust is safe for use as a material in building projects. In fact, Veolia says its work diverts about 80% of the dust and materials that would otherwise be headed for a landfill.

Which brings us back to the money. Between reclaiming valuable minerals and significantly cutting landfill fees, Veolia says it can give cities a break on street sweeping fees. That, in turn, makes recycling road dust an even more golden idea.

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Kevin Ebi is a staff writer and social media coordinator for the Council. Follow @smartccouncil on Twitter.

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