New Cement Absorbs More CO2 Than Production Emits

guardian.co.uk:

Standard cement, also known as Portland cement, is made by heating limestone or clay to around 1,500C. The processing of the ingredients releases 0.8 tonnes of CO2 per tonne of cement. When it is eventually mixed with water for use in a building, each tonne of cement can absorb up to 0.4 tonnes of CO2, but that still leaves an overall carbon footprint per tonne of 0.4 tonnes.

Novacem's cement, which has a patent pending on it, uses magnesium silicates which emit no CO2 when heated. Its production process also runs at much lower temperatures - around 650C. This leads to total CO2 emissions of up to 0.5 tonnes of CO2 per tonne of cement produced. But the Novacem cement formula absorbs far more CO2 as it hardens - about 1.1 tonnes. So the overall carbon footprint is negative - ie the cement removes 0.6 tonnes of CO2 per tonne used.

Read the whole story: guardian.co.uk

Comments

[mattress 1]

Who cares? CO2 is not responsible for global warming!! The SUN is responsible for Global Warming...just as it has been for millions of years. Wake up people. Whenever the Propoganda Machine is telling you something....you can usually bet it is not correct.

[newshawk14]

A number of years ago there was an article in Scientific American, about the production of very high
strength cements. The process used liquid CO2 under high pressure to rapidly cure the cement and
provided an almost threefold increase in strength. A similar process using fly ash made lightweight,
very strong, and fireproof roof tiles. It's a pity that the TVA didn't choose to develop the process.

[earllutz]

This is probably the same GLUE that NASA was required to use on the shuttle's external fuel tank. It was changed out because it was more "environmental"

It did not hold the foam on -- This is why it burned up over Texas.

Besides, how much CO2 do you think we create with freeking GLUE.

GLUE? Get a CLUE folks

[newshawk14]

Where did I ever mention glue? Read a post, before commenting on it.

[SwingingFromCenter]

And nobody in America will ever use it, because it undoubtedly "costs too much"

[RTIII]

This is FANTASTIC news, but they better get on with it! One problem is that the carbon dioxide that has the most negative effect is high in the atmosphere. Capture that CO2 while it's still available to be captured - hurry up guys!
.

[Tom95134]

This is going to be a long time coming into general use. Portland cement has a history going all the way back to the Romans as to its suitability and ability to retain its characteristics over time. On top of that, Portland cement will setup under water.

It seems to me that they would be better off working on ways to improve the processing of Portland cement and make use of the out gassed carbon in a closed processing cycle. I don't think I'll be holding my breath waiting for this the econ-cement to make it into general use.

[Topsailsman]

"It seems to me that they would be better off working on ways to improve the processing of Portland cement and make use of the out gassed carbon in a closed processing cycle." Yes, refining current technology is great, but I'm sure you didn't mean that we shouldn't put effort into completely new concepts? Otherwise, wouldn't we still be improving the vacuum tube?

[derekc06]

filtering and processing carbon emissions is not the answer...

[GretaR]

Wow, that's sexy. I just love innovative thinking of the "do no harm" variety.

[Biofriendlyblog]

Well, that's a good idea. It's nice to see a product that apparently produces a negative carbon footprint. Hopefully it works well.

[Wilburrr]

What is the coefficient of expansion for this stuff? Steel reinforced concrete works because the expansion coefficients for those two materials are nearly equal. Nuclear power plants have huge carbon footprints for all of the concrete required. If this magnesium silicate material can be paired with steel to give similar results as the traditional concrete then we have solved one (but only one) of the huge problems with going to nuclear energy alternatives.

[derekc06]

nuclear energy shouldn't be an alternative...

[SwingingFromCenter]

You're right. Nuclear energy should be the standard, not the alternative