Climate change: How slag can remove CO2 from the air
Scientists in Wales are looking at how slag heaps can be used to remove CO2 from the air in the fight against climate change.
Slag is the waste left over from an old ironworks and the researchers at Cardiff University are using it to suck the gas away.
The technique isn't perfect, and scientists say more needs to be done to solve the wider global warming problem, but this process could help.
Video Journalist: Laura Foster
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