Naked Science Forum

Life Sciences => The Environment => Topic started by: peppercorn on 25/05/2010 15:10:51

Title: Can cement really be green?
Post by: peppercorn on 25/05/2010 15:10:51
"Today companies around the world are vying to be the first to commercialise cements that can be made either by absorbing more than their production generates, or without emitting carbon dioxide at all."

http://www.newscientist.com/article/dn18885-green-machine-cementing-greener-construction.html


"To produce the cement, Semidolime is mixed with water and power-plant flue gas, which typically contains significant levels of CO2."

Who'd 've thought it?
Title: Can cement really be green?
Post by: Geezer on 25/05/2010 19:17:25
Sure. You can put dye in it!

I think my mum was way ahead of these guys, although she called her version Semolina.

OK - enough with the bad jokes!



That's very interesting Peppercorn. Thanks for sharing.
Title: Can cement really be green?
Post by: echochartruse on 26/05/2010 19:29:56
Absolutely amazing that they can grab CO2 from the atmosphere to make the cement.
'The process does, however, release a pure stream of CO2, but this can be captured and compressed for geological storage, says Sceats.'http://www.newscientist.com/article/dn18885-green-machine-cementing-greener-construction.html
Doesn't cement continually give off CO2 even after, years after, for the rest of its life?
Title: Can cement really be green?
Post by: Mazurka on 27/05/2010 10:51:47
I thought it was the opposite - portland cement absorbs CO2 as Calcium di-(Hydroxide) is converted into calcium Carbonate.

I believe that some people have tried to accelerate this process by using super critical CO2 to effectively turn concrete into a limestone conglomerate...