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Significant metal deposits in the ashes
Since 1985 waste incineration has increased dramatically, and consequently the quantity of metals that remain in the ash.
Nicklas Svensson, research associate at the Environmental Technology and Management at Linköping University (LiU), in conjunction with the giant regional energy company Tekniska Verken has studied how much metal this might amount to.
“There’s between 10 and 15% metal in the bottom ash and around five percent in the fly ash,” he states.
The ash is currently deposited in landfill; over the course of a year this amounts to nearly 1 million tonnes, where a tonne corresponds to one cubic metre.
Waste incineration from 1987 to 2010 has given rise to 11 million tonnes of ash, which also constitutes around 1.5 million tonnes of metal of various types present in the ash.
A large portion of the ash is currently used as construction material in places such as the landfills.
“We need to research further to find out which metals are of interest economically and environmentally for reclamation from the ashes,” Svensson says.
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Since 1985 waste incineration has increased dramatically, and consequently the quantity of metals that remain in the ash.
Page responsible:
anna.nilsen@liu.se
Last updated: Wed Mar 14 15:46:24 CET 2012
