Heavy industry takes a lot of blame for greenhouse gas emissions but at least one segment may be able to do something to give a little back. Steelworks around the world emitting large quantities of carbon dioxide but scientists report that a byproduct of steel production could be used to absorb that greenhouse gas and help control global warming. The study is in Industrial & Engineering Chemistry Research.
Professor Mourad Kharoune and colleagues point out that production of one ton of steel releases up to one ton of CO2. With global steel production standing at 1.34 billion tons in 2007, that adds up to a substantial contribution of carbon dioxide.
Kharoune suggests a new method to sequester, or capture, carbon dioxide so that it does not contribute to global warming – using steel slags, which are complex mixtures of compounds produced during the separation of the molten steel from impurities.
In the study, Kharoune suggests that electric arc furnace (EAF) and ladle furnace (LF) slag suspensions could be used for greenhouse-gas sequestration. According to the report, the ladle furnace slag suspension's capacity to sequester emissions was 14 times higher than that of the EAF suspension, possibly due to the LF's higher content of a rare mineral called portlandite.
Article: Danielle Bonenfant, Lynda Kharoune, Sébastien Sauve´, Robert Hausler, Patrick Niquette, Murielle Mimeault and Mourad Kharoune, 'CO2 Sequestration Potential of Steel Slags at Ambient Pressure and Temperature', Ind. Eng. Chem. Res., 47 (20), 7610–7616, 2008. 10.1021/ie701721j
(Wikipedia entry on Slag)
And I also say it's jolly good for the garden! (Unless you're growing Rhododendrons and similar lime-hating plants.) Especially it stops the soil in pots from going sour, when you're dealing with long-termers like cacti or the mesembryanthemum family.
Robert H. Olley
Physics Department
University of Reading
England