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Green Cement Absorbs Carbon

kdawson posted more than 4 years ago | from the do-not-like-green-cement-and-ham dept.

Earth 213

Peace Corps Online writes "Concrete accounts for more than 5 percent of human-caused carbon dioxide emissions annually, mostly because cement, the active ingredient in concrete, is made by baking limestone and clay powders under intense heat that is generally produced by the burning of fossil fuels. Now Scientific American reports that British start-up company Novacem has developed a 'carbon-negative' cement that absorbs more carbon dioxide than it emits over its life cycle. The trick is to make cement from magnesium silicates rather than calcium carbonate, or limestone, since this material does not emit CO2 in manufacture and absorbs the greenhouse gas as it ages. 'The building and construction industry knows it has got to do radical things to reduce its carbon footprint and cement companies understand there is not a lot they can do without a technology breakthrough,' says Novacem Chairman Stuart Evans. Novacem estimates that for every ton of Portland cement replaced by its product, around three-quarters of a ton of CO2 is saved, turning the cement industry from a big emitter to a big absorber of carbon. Major cement makers have been working hard to reduce CO2 emissions by investing in modern kilns and using as little carbon-heavy fuel as possible, but reductions to date have been limited. Novacem has raised $1.7M to start a pilot plant that should be up and running in northern England in 2011."

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213 comments

Strength? (5, Insightful)

plnb (579253) | more than 4 years ago | (#29032787)

No mention in the article of the strength of the new material. How would this compare to regular concrete?

Re:Strength? (1, Insightful)

Anonymous Coward | more than 4 years ago | (#29032819)

Or the ramifactions of the extra weight caused by absorbing the CO2..

Re:Strength? (-1, Flamebait)

Anonymous Coward | more than 4 years ago | (#29032869)

CO2 is lighter than air retard.

Re:Strength? (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#29032901)

Except regular cement doesn't absorb air so g.p. has a valid point retard.

Re:Strength? (5, Funny)

Anonymous Coward | more than 4 years ago | (#29033299)

weight of air, approximately 28 grams per mole
weight of carbon dioxide, 44 grams per mole
Being a tard on /., priceless. Also weightless.

Re:Strength? (-1, Flamebait)

Anonymous Coward | more than 4 years ago | (#29033385)

What planet are you on, moron?

Re:Strength? (-1, Flamebait)

Anonymous Coward | more than 4 years ago | (#29033445)

Look MS boy, if CO2 was lighter than air, it would RISE to the top. The reason is that air is nothing more than an ocean of gases. The best example is Helium and Hydrogen. BOTH rise to the top of ocean due to their being lighter. They will also slowly escape our planet. OTH, had CO2 been lighter than N2, then plants would not exist and to be honest, we would not breath (our rate of breaths is determined by amounts of CO2, not O2).

What amazes me is the total lack of logic on a site devoted to software. Makes me wonder about how many bugs there really are out there. I know that it is a lot, but I am starting to suspect that even my worst fears do not do it justice.

Re:Strength? (1, Informative)

Anonymous Coward | more than 4 years ago | (#29033809)

we would not breath (our rate of breaths is determined by amounts of CO2, not O2)

Not quite. It's determined by CO2, yes, but it's the CO2 in the blood that determines it, not atmospheric CO2.

Basically the intake is kept equal to the exhaust.

Re:Strength? (0)

Anonymous Coward | more than 4 years ago | (#29033273)

But maybe someday we can reuse this concrete as a carbon-based fuel source - neo-coal or such.

Re:Strength? (3, Insightful)

Z00L00K (682162) | more than 4 years ago | (#29033805)

The weight may not be the issue, but will the structure and volume change when it absorbs CO2 over time?

If there is a volume change then there may be problems with warping and cracking. It's not easy to make a cement that can handle all construction requirements.

Then there is also the concerns about the availability of the magnesium silicates used.

Re:Strength? (5, Funny)

HeLLFiRe1151 (743468) | more than 4 years ago | (#29033891)

No need to worry about the availability of Magnesium Silicates, they just found the mother-lode in the South American rain forest.

Re:Strength? (1)

LaZZaR (216092) | more than 4 years ago | (#29032825)

My thoughts exactly, does it not have to store the carbon somewhere? Of course I have no knowledge in this area, but sureley that would change the structural integrity of the concrete over time? Could someone more knowledgable comment on this?

Or, for all we know, because its absorbing carbon it could very well make it stronger.

Re:Strength? (2, Informative)

Anonymous Coward | more than 4 years ago | (#29034109)

All concrete absorbs CO2 as it cures. They don't bother to tell you that. It only gives off CO2 in its manufacture. Basically what I they're talking about is breaking down calcium sulfates instead of calcium carbonates to make one of the primary ingreedient. They're probably also using more calcium overall...making it a little more like masonry mortar. Were we to make the bulk of our concrete with this process we would quickly surpass our need for sulfuric acid and other sulfates and the resulting pollution would make CO2 look like the elixir of life. Hmmm, come to think of it CO2 just about is the elixir of life anyway. We really need to concern ourselves more with actual pollution and less with CO2.

As for structural integrity...it will increase over time, just like normal concrete. While concrete may be considered to be fully cured within a few days it takes decades before it reaches full strength (sometimes as much as twice as hard as when it's first considered "fully cured")

Re:Strength? (4, Insightful)

mysidia (191772) | more than 4 years ago | (#29032847)

Strength is important, and so is longevity.

I don't want to be in the car on that 50 year old bridge that collapses, because they didn't do right trials to detect aging and absorbing CO2 having an adverse effect on the material's strength over time.

Concrete is a rather proven material that has been proven over hundreds of years; spontaneously replacing it now could be highly dangerous.

Much like replacing the OS on a computer system that's been chugging a way for 500 years, with a brand new release version.

Sure, there may be an efficiency improvement. There can also be unexpected bugs.

Re:Strength? (2, Interesting)

Anonymous Coward | more than 4 years ago | (#29032927)

Sure, hundreds of years, if not more. Do you mean that this is the first time someone has changed the recipe?

Re:Strength? (2, Informative)

Sensiblemonkey (1539543) | more than 4 years ago | (#29033443)

A *lot* more than hundreds of years. The Romans used concrete all over the place. Even the Pantheon's dome is concrete.

Re:Strength? (2, Insightful)

jelle (14827) | more than 4 years ago | (#29033783)

Do you seriously believe that modern concrete is the same recipe, strength, and longevity as roman concrete?

Re:Strength? (1)

Sensiblemonkey (1539543) | more than 4 years ago | (#29034295)

Do you seriously believe that modern concrete is the same recipe, strength, and longevity as roman concrete?

lol!! It's not the same recipe, but it's still technically concrete.

FYI, the parent was indicating that the recipe might have been altered in the past two hundred years or so. I was pointing out that an even greater time frame existed in which to have different recipes emerge. There's nothing in my post to indicate otherwise.

Which leads me to ask: Do you seriously believe any of us to credit you with any semblance of social skills?

Re:Strength? (5, Insightful)

GeigerBC (1056332) | more than 4 years ago | (#29033057)

You're right in that we want strong and durable concrete. As another poster pointed out we are constantly changing the concrete mix proportions and admixtures. Admixes themselves are relatively new (~50 years) in the grand scheme of making concrete. It gets introduced slowly...and the universities then test it beyond belief for different properties. Maybe you'd like to be a grad student in civil engineering and make hundreds, or perhaps thousands of ever so slightly different mixes to determine the properties of your variable. I'm all for making concrete more "green" and I figure the universities and companies will test it before they use it in important projects.

Re:Strength? (1)

bitrex (859228) | more than 4 years ago | (#29034283)

For a moment I thought you were going to say "Maybe you'd like to be a grad student in civil engineering and make hundreds, or perhaps even thousands of dollars!"

Re:Strength? (0)

Anonymous Coward | more than 4 years ago | (#29033473)

"Much like replacing the OS on a computer system that's been chugging a way for 500 years, with a brand new release version. "

good analogy!

...

Re:Strength? (1)

Xtravar (725372) | more than 4 years ago | (#29033583)

All of the roads and bridges aren't going to be replaced at once, and especially not any bridges that rely on concrete for structural integrity.

Not to mention, every time a material like this comes out, it's prohibitively expensive, so probably only eccentric European cities will even try it.

I wouldn't worry too much about it... nobody's going to take away your concrete just yet.

Re:Strength? (0)

Anonymous Coward | more than 4 years ago | (#29033687)

I don't want to be in the car on that 50 year old bridge that collapses, because they didn't do right trials to detect aging and absorbing CO2 having an adverse effect on the material's strength over time.

No need to worry, the studies have been done and the material's strength actually increases over time due to the absorbtion of CO2.

It's a win-win all round.

Re:Strength? (1)

Thanshin (1188877) | more than 4 years ago | (#29034085)

Much like replacing the OS on a computer system that's been chugging a way for 500 years, with a brand new release version.

Sure, there may be an efficiency improvement. There can also be unexpected bugs.

And we could even use a car analogy.

It would be like replacing the fuel on a car that's been chugging a way for 500 years, with a brand new fuel type.

Or even for a mix of fuel types.

We could call that mix "mutant", or "hybrid", or something like that.

Re:Strength? (0)

sadness203 (1539377) | more than 4 years ago | (#29033085)

What I want to know is... If we build a basement with that, Will it will absorb enough CO2 to kill / damage brain of a geek. I fear some parents might take drastic measure to help us out of the house !

Re:Strength? (1)

DerekLyons (302214) | more than 4 years ago | (#29034173)

No mention in the article of the strength of the new material. How would this compare to regular concrete?

Who cares dude? It's effin' green! just like the cash we can get from investors because it's like fashionable to investing in things that are green!

Re:Strength? (0, Troll)

icebike (68054) | more than 4 years ago | (#29034255)

No mention in the article of the strength of the new material. How would this compare to regular concrete?

Not only no mention of the strengths, or the weight of absorption, but also no mention of the huge body of knowledge of cement that the building industry has amassed over time.

There is a cement for every purpose, using formulas worked out over hundreds of years, virtually every aspect of it is well understood.

Who knows about the new stuff?

Who builds the first bridge, or sky scraper that will get heavier (by 2/3rds according to the article) as it ages?

And what about the fossil fuels used to make the cement? Do they remain the same?

People are going nuts looking for CO2 emission sources in all the wrong places. Look at the chart of CO2 emission sources. Soda Ash production (the category that includes cement) is WAY down the list. Microscopic.
http://www.epa.gov/climatechange/emissions/co2_human.html [epa.gov]

The effort would be better spent building Nuclear generation plants and figuring out what to do with spent nuclear fuels, because a 10% reduction in CO2 emission from fossil fuels would totally swamp any reduction due to cement manufacturing.

Of course the same scare tacticians who see the CO2 boogie man under every bed also won't let us build Nukes. So we cast our hopes in cement, literally and figuratively.

Less CO2 = $Green$ (3, Insightful)

Scubaraf (1146565) | more than 4 years ago | (#29032835)

I see one of the early tags is 'negligible.'

Maybe it is in terms of global CO2 levels, but under a cap and trade system, this will turn an industry that might have to buy CO2-emission rights into one that could make money selling them!

Re:Less CO2 = $Green$ (5, Insightful)

Mad Merlin (837387) | more than 4 years ago | (#29032999)

Even if it is negligible, "going green" is the trendy thing to do nowadays, so as long as it seems like they're making an effort, that's far more important than if it actually helps.

Re:Less CO2 = $Green$ (3, Funny)

Bemopolis (698691) | more than 4 years ago | (#29034041)

Considering the volume of carbon dioxide emitted by the loud-mouthed opponents to the very concept of global warming, I'll take even a palliative corporate effort to ameliorate the problem. For now.

Re:Less CO2 = $Green$ (3, Insightful)

Dragonslicer (991472) | more than 4 years ago | (#29033135)

A solution that fixes only 1% of a problem may be considered negligible, but gather together a hundred such "negligible" solutions and see what you get.

Re:Less CO2 = $Green$ (4, Funny)

tehSpork (1000190) | more than 4 years ago | (#29033713)

An alarming lack of airborne greenhouse gasses leading to a dangerous trend of global cooling?

Re:Less CO2 = $Green$ (1, Offtopic)

hairyfeet (841228) | more than 4 years ago | (#29033727)

Am I the only one that when reading or hearing of "cap and trade" automatically thinks of that old scam the Catholics had going several centuries ago where you could fuck your neighbor's wife, or steal his land, just as long as you bought your 'get out of hell free" card from the church?

And why do I get this really nasty feeling that we will find Goldman Sachs sitting their behind the scenes ready to cash in? Am I the only one that when hearing all this "going green" with huge numbers and taxes attached to it think "total scam"? if you want to cut emissions, fine, then cut them. But this cap and trade nonsense just smells like another way for those like Goldman Sachs to make yet another killing while giving the middle class the bills AGAIN. Or is it just me?

Re:Less CO2 = $Green$ (0)

Anonymous Coward | more than 4 years ago | (#29034143)

Cap and trade has a number of advantages over other ways to allocate CO2 emissions.
* It allows us to set the cap at whatever we want, and be assured that the amount of (legal) CO2 emissions will not exceed that value. Rather than trying to model how use will fluctuate based on CO2 taxes or other systems, we will have a firm value for the total emission numbers.
* It doesn't matter to the environment who emits the CO2. You seem to be worried about a single company emitting disproportionately high amounts of CO2 (at least, I think that's what you're getting at with the wife fucking analogy). However, if a company does this, it will necessarily be accompanied with a corresponding decrease in the amount of emissions that other companies are allocated (hence the "cap").
* This sort of allocation problem is the type of thing that the market system solves easily and efficiently. I'm a pretty thorough bleeding heart, and even I can admit that the free market is the best way to solve this.

Who honestly cares about carbon? (0, Insightful)

Anonymous Coward | more than 4 years ago | (#29032839)

What is the purpose of going to all the trouble of actually creating a product that produces more or less carbon. Global warming may or may not be happening, but if so we don't exactly know what is causing it and we definitely can't stop it - but the companies that seek to profit from global warming hysteria don't care in the slightest that anything is actually being done about carbon - just that one pays the extra global warming carbon tax.

Try harder next time. (5, Funny)

Capsaicin (412918) | more than 4 years ago | (#29033761)

Global warming may or may not be happening.

That's a tautology much like "water may or may not be wet," so by definition it's logically true. "Global warming is happening." That's a statement of scientific fact, it's empirically true.

... we don't exactly know what is causing it ...

We don't know exactly, however it has been established beyond any reasonable doubt that human activity is a major contributor.

... and we definitely can't stop it

Up to that point this was such a beautiful example of agnatology [wikipedia.org] relying on nothing but formally True statements. Why did you have to ruin it? How very disappointing!

Can you help me Slashdot? (-1, Troll)

Anonymous Coward | more than 4 years ago | (#29032841)

My dad is a nigger kike and my mom is a spic muslim. Of course I have a donkey-sized dick due to my dad but I also speak Hebrew, Spanish, Arabic and English. What does that make me?

Re:Can you help me Slashdot? (0, Funny)

Anonymous Coward | more than 4 years ago | (#29032913)

An mal-adjusted, racist asshole?

Re:Can you help me Slashdot? (0, Offtopic)

Ethanol-fueled (1125189) | more than 4 years ago | (#29032957)

Of course I have a donkey-sized dick due to my dad

You have his nose, but not his dick. How about the three of you get nose jobs and then you and daddy can take turns waxing momma's back and asshole.

Have fun at the airport you mutt-terrorist fucks!

Re:Can you help me Slashdot? (-1, Flamebait)

Anonymous Coward | more than 4 years ago | (#29032993)

Obama?

Re:Can you help me Slashdot? (1, Funny)

Anonymous Coward | more than 4 years ago | (#29033245)

Unintelligible.

Isn't magnesium silicate... (2, Interesting)

1zenerdiode (777004) | more than 4 years ago | (#29032845)

the composition of asbestos?

Re:Isn't magnesium silicate... (5, Informative)

reverseengineer (580922) | more than 4 years ago | (#29033013)

It's the composition of quite a few minerals, including asbestos, but also talc and soapstone. The issue with asbestos isn't the chemical composition per se, but rather its inclination to break into micron-sized fibers that can be deposited in the lungs. Compare fine silica, which is nearly chemically inert, but poses a serious danger if inhaled.

Re:Isn't magnesium silicate... (1, Informative)

Anonymous Coward | more than 4 years ago | (#29033181)

amorphous silica is fine to inhale even if it is really fine dust particles. crystalline silica is what will give you silicosis..

Re:Isn't magnesium silicate... (1)

Michael Woodhams (112247) | more than 4 years ago | (#29034057)

The company's site is very light on detail, but I did find this in one of their (two) press releases:
Novacem's revolutionary technology is based on magnesium silicates rather than limestone
(calcium carbonate) as is used in traditional Portland cement. Global reserves of magnesium
silicates are estimated to be in excess of 10,000 billion tonnes. The company's technology
converts magnesium silicates into magnesium oxide using a low carbon, low temperature process,
and then adds special mineral additives to produce Novacem cement.

I still have many questions, beyond the strength and durability issues others have raised.
Are suitable magnesium silicate deposits common, or will this require shipping bulky material over long distances? Will the process be a simple (quarry->grind up->heat) sequence or will some refining be required? What about those "special mineral additives": are they abundant and non-toxic?

Severe doubts (4, Interesting)

sofar (317980) | more than 4 years ago | (#29032859)

This sounds like a concrete nightmare:

If a material absorbs so much CO2 over it's lifespan, it significantly alters the chemical composition and therefore strength.

I doubt any builder will use this material unless it's been proven that the new material is sufficiently stable.

Example: as a geology student, I ran into an area in central spain with lots of Gypsum sediments (Ca|MG.SO4). Putting limestone and concrete buildings on this sediment wasn't done until the 20th century, but all the buildings built in that area are long gone, even though in nearby towns they still stand tall. Reason? The Gypsym in the soil chemically eats the mortar and limestone (CaCO3) out of the structure on top of it, making it crumble within a few decades. The Gypsum areas are largely a wasteland where only very few buildings remain.

Now, Mg.Ca-CO3 (dolomite limestone) is largely as stable or more stable than pure limestone, and certainly harder, but any new formula for the glue in concrete will have to pass the test of time before it will be widely adopted, especially in e.g. bridges and skyscrapers...

Perhaps we can start with the interstates, nobody would notice if they started to crumble early ;)

Re:Severe doubts (1)

zygotic mitosis (833691) | more than 4 years ago | (#29032949)

Now, Mg.Ca-CO3 (dolomite limestone) is largely as stable or more stable than pure limestone, and certainly harder...

That's dolomite, baby.

Re:Severe doubts (0)

Anonymous Coward | more than 4 years ago | (#29032985)

If a material absorbs so much CO2 over it's lifespan, it significantly alters the chemical composition and therefore strength.

So much? How much?

it absorbs more carbon dioxide over its life cycle than it emits [...] this material does not emit CO2 in manufacture and absorbs the greenhouse gas as it ages

So it absorbs more than zero.

Re:Severe doubts (0)

Anonymous Coward | more than 4 years ago | (#29033021)

um. has the fixation process of cement changed since it was a carbon neutral process....?
http://books.google.com/books?id=Ldo3AAAAMAAJ&lpg=PA2&ots=DIBo8wY4G3&dq=cement%20carbon%20resorption&pg=PA2#v=onepage

i mean, negative CO2 might be a sweet breakthrough. but i'm pretty sure cement has never been CO2 positive. it has to resorb CO2 to solidify, doesn't it?

Re:Severe doubts (4, Interesting)

Anonymous Coward | more than 4 years ago | (#29033163)

Interstates, roads, curbs, sidewalks, etc...
Structure and load bearing however, strength is where it is at. Also most concrete is however very brittle. It is good at load distribution not in actual strength.

Also many times these structures are torn up and tossed into large piles. They could continue to soak up carbon.

The idea is sound, but in practice probably wouldnt be so good as you pointed out. In some applications it is a decent idea.

Re:Severe doubts (2, Informative)

ATestR (1060586) | more than 4 years ago | (#29033381)

It is good at load distribution not in actual strength.

More precisely, concrete is good in compression, but poor in tension. That's why you fill it with steel bars if it has to take any bending forces that would put part of it in tension.

Actually (1)

WindBourne (631190) | more than 4 years ago | (#29033469)

I would think that sidewalks and minor side roads would be the place to start. If EU is going to start this, then perhaps we should order some of this and put it into various places (none structural) to see how it lasts. In fact, just thinking about it, it MIGHT actually improve the roads. It would slowly gain weight which MIGHT also strengthen bonds in it, though I notice that they have said NOTHING about that. I would think that if it did get stronger, then they would say something. Regardless, if this is cheaper, it would be great on sidewalks.

Re:Severe doubts (0)

Thanshin (1188877) | more than 4 years ago | (#29034129)

as a geology student, I ran into an area in central spain with lots of Gypsum sediments (Ca|MG.SO4).

Ca|MG.S04?

Dang! They have strange area names in Spain.

I wonder if they use that place as a surname too.

"I am don Quijote de la Ca|MG.S04. "

Re:Severe doubts (1)

sofar (317980) | more than 4 years ago | (#29034335)

Ca|Mg.SO4 is another way to write Gypsum. It is not nearly as strange as some area names in Spain :)

Seriously... (4, Insightful)

redmond (611823) | more than 4 years ago | (#29032861)

"The building and construction industry knows it has got to do radical things to reduce its carbon footprint and cement companies"

Seriously? At least here in the Midwest (USA), construction bids still go to the lowest bidder and there are huge piles of construction waste that go straight to the landfill. They won't change until someone makes them change.

Re:Seriously... (1)

blindseer (891256) | more than 4 years ago | (#29034059)

They will be forced to change by tax and trade. If carbon emissions are taxed then the lowest bidder will likely be the one with the smallest CO2 output.

Re:Seriously... (0, Troll)

icebike (68054) | more than 4 years ago | (#29034305)

the lowest bidder will likely be the one with the smallest CO2 output.

I see where this is going.

Never mind the real costs. Lets set building prices based on some half baked idea that CO2 emission is more dangerous than anything else that could possibly happen.

More parking lots then? (0, Flamebait)

Bodhammer (559311) | more than 4 years ago | (#29032881)

Well, we better start cutting down some more rainforests and start pouring more swimming pools and parking lots if we are ever going to beat this global warming thing!

Re:More parking lots then? (0)

Anonymous Coward | more than 4 years ago | (#29032979)

Well, we better start cutting down some more rainforests and start pouring more swimming pools and parking lots if we are ever going to beat this global warming thing!

This is a geek site. If you want to fight global warming by building more geek friendly concrete structures then build more basements! There's a serious shortage and it'll give geeks a chance to be green and live in a comfortable familiar environment.

What is the life span? 200 years to break even? (1, Interesting)

Anonymous Coward | more than 4 years ago | (#29032899)

What is the life span?
How much if a cost increase would it take to reduce our carbon dioxide emissions by using this product?
Does it have the same strength? Is it completely interchangeable with today's concrete?
Is it possible to retrofit current concrete plants? Do we have to build all new concrete plants?

I have a similiar green question about concrete (3, Interesting)

Anonymous Coward | more than 4 years ago | (#29032925)

Fly ash, which is the ash waste from burning coal is also being used in concrete to lessen the amount of C02 concrete creates as well as improve strength. My question is since this fly ash has a high amount of toxins(heavy metals) in it, would the toxins be locked in the concrete or would they seep out if exposed to water or other stresses over time.
      I am curious to know this because apparently fly ash can make concrete easier to work with in insulated concrete form construction and because other types of materials that compete with concrete seem to be using it. Gigacrete.com ( supposedly 10,000 psi strength) though not for structural use is an example. I can't tell if they are using weasel words though because they claim there binder is nontoxic, I can't tell if they are purposely talking about the binder being non toxic and not the fly ash.
    I hope someday to build a house out of ICF's (insulated concrete forms), I guess I must have taken to heart that story of the three little pigs when I was young.

Re:I have a similiar green question about concrete (4, Informative)

SomeKDEUser (1243392) | more than 4 years ago | (#29033965)

Fly ash is actually widely used as a supplementary cementitious material. It has all sorts of excellent properties, it reduces porosity, increases durability mitigates ASR. It is a so-called pouzzolane, which means it reacts with the carbon hydroxide produced by the reaction of the cement and transforms it into calcium-silicate hydrate which is the main responsible for the strength of cement (C-S-H is the main product of the reaction of cement with water)

In fact, we are running out of sources of fly ash to put in cement. So basically, no, there is no risk, or we would have known by now. Also, you have to realise that FA is essentially pure amorphous silica, and that heavy elements would only be there as traces and stay trapped as the FA reacts.

Inaccurate (2, Informative)

Brian Gordon (987471) | more than 4 years ago | (#29032931)

Novacem estimates that for every ton of Portland cement replaced by its product, around three-quarters of a ton of CO2 is saved, turning the cement industry from a big emitter to a big absorber of carbon

You mean turning the cement industry from a big emitter to a small emitter...

Re:Inaccurate (1)

Mad Merlin (837387) | more than 4 years ago | (#29033031)

Nobody said that a ton of concrete produces a ton of CO2.

Re:Inaccurate (0)

Anonymous Coward | more than 4 years ago | (#29033173)

But "a ton" means "a lot". So if you save three quarters of "a lot", that means one-quarter is unsaved, and hence still released.

In this house we obey the laws of qualitative approximations!

Re:Inaccurate (1)

Nyall (646782) | more than 4 years ago | (#29034097)

This is being compared to portland cement. Just to pull numbers out of my butt, if the production of one ton of portland cement releases 6 tons of CO2, then one ton of this new cement (which use 3/4 tons less than portland) will release 5.25 tons of CO2.

Re:Inaccurate (1)

Nyall (646782) | more than 4 years ago | (#29034221)

p.s. since the summary terms it "carbon negative" those numbers probably aren't the best...

Re:Inaccurate (1)

SomeKDEUser (1243392) | more than 4 years ago | (#29034001)

Well, no, but a ton of cement, yes. You cannot do anything about it, because the reaction that transforms the rocks into cement liberates CO2. The little abstract at the to is completely wrong about the fossil fuels: a cement plant will burn anything and is typically doubling as an incinerator. The reason there are masses of CO2 produced is chemical, and unless you give up on cement, you will never reduce that.

In fact, to reduce the emissions, this is exactly what the cement companies do: they replace part of the cement with other materials, such as slag, fly ash rice ash hulk which harden not as fast or only with the product of cement hydration but yield better properties in the long run

Is it does me or does (1)

carp3_noct3m (1185697) | more than 4 years ago | (#29032963)

The summary jump to the conclusion that "is made with a process that traditionally uses fossil fuels" to "emits carbon dioxide" , albeit without saying the latter? Wouldn't the more effecient thing to do be to figure out a way to make cement without using traditional methods requiring fossil fuels? I guess nowadays anything you call green and make sound even close to like it helps the environment makes the hippies happy and business believe you..sigh...

Re:Is it does me or does (1)

Nyall (646782) | more than 4 years ago | (#29033233)

Ah yes, why do xyz when abc would be so much magically better? Because people are always tackling problems from all sides.

A quick googling tells me that cement production requires baking the stuff at 2700F so I presume abc would mean either:
a) Get rid of the need to bake it at such a temperature.
b) Generate that heat with a different method.

Not to say that A is impossible but it sounds like a really hard problem. If someone solves it they deserve their billion dollars.

And B is also hard because I suspect the best way to generate 2700 degrees is with fire. At this point I'm too lazy to google how high electricy->heat conversion can go (especially for the scales that a cement production plant needs) Any experts out there?

Re:Is it does me or does (1)

benjamindees (441808) | more than 4 years ago | (#29033253)

The summary is confusing. The CO2 comes from two places, from the fuel burned to heat the limestone (calcium carbonate), and from the calcium carbonate itself. Simply using renewable heating methods would not eliminate all of the CO2 emissions as the majority result from the chemical reaction of the material itself. The solution is to use a different material that does not emit CO2 or will re-adsorb CO2 over it's lifetime without losing strength.

Re:Is it does me or does (1)

SomeKDEUser (1243392) | more than 4 years ago | (#29034019)

Amazing! someone read the article! Indeed, madam/sir, you are right. I did not read the article (wondered about the comments), but I work on concrete -- IAACS (I am a concrete scientist)...

Oh brother... (-1, Flamebait)

jav1231 (539129) | more than 4 years ago | (#29032977)

Frankly, the mention of the term "carbon footprint" puts this squarely in the "hype" category.

Re:Oh brother... (4, Insightful)

thelandp (632129) | more than 4 years ago | (#29033361)

Frankly, the mention of the term "carbon footprint" puts this squarely in the "hype" category.

Why did that get modded 5 insightful? Carbon Footprint is a valid and useful term.

The only reason I can see why some might like the above comment is if they are so conservative on climate change, they reject even the terms used in discussing it.

It would almost qualify as an example of the logical fallacy known as the "Appeal to Ridicule" but it wasn't quite intelligent enough.

http://en.wikipedia.org/wiki/Appeal_to_ridicule [wikipedia.org]

Re:Oh brother... (0)

Anonymous Coward | more than 4 years ago | (#29033651)

I always seem to be 5 years ahead of my time (Yeah, yeah, but just a feeling I get sometimes.). I was all into Google when it wasn't even on the map. (Darn it for being so young I couldn't invest or work at the time.) Anyway, I was also fully in belief of the whole green movement as well. Most of it is still important and very valid in improving the lives of humanity. However, the entire global warming argument, I think the best approach is to throw the baby out with the bathwater. I have examined the data myself (as have many slashdotters at this point it seems.) I won't say it's a consensus, but it is certainly a movement away from the whole anti-carbon agenda. There are obviously a great many on both sides, but unless I'm completely wrong, the slight majority here is starting to think that indeed, the global warming is a farce. At least as far as humans are concerned.

The human produced carbon is not causing a warming, and even if it was, admittedly we're talking about a 1/20th of a degree in change/preventive change. This is with the ideal pro-green model. The cost of which, well I don't have a handy number here. In the US alone the costs, and hidden costs are going to be close to astronomical.

I mean we are really relying on measurements from so long ago. Who knows how truly accurate the devices were anyway? At least in today's digital age, we have a little more resolution on the temperature scale. [less errors from reading the mercury in the thermometer.] Since we really are talking about 1/20th of a degree in the model, those small errors do throw a large wrench into the model. The Nasa website has a place where you can compare climates. Comparing the 1920's to today makes it look like an agressive warming trend. Comparing... I think I tries both 70's and 80's to today it showed quite the cooling trend. Climates fluctuate anyway, and I won't believe for a second that someone can come up with an accurate model that will show what the temperature change will be if humans cut back on the extremely small volume of carbon that is released today. [Small when compared to all carbon sources, and infinitesimal when looked at as a greenhouse gas.] We would be much better off it seems if we cut back on water vapor... but then it might not rain as much... and don't clouds reflect light anyway?... Almost too many variables to account for, especially in a model that is inherently not stable.

Then there's the part of the argument that goes... global warming? GREAT NEWS!
Since we as humans benefit from a small warning. There is a net-gain in food production anyway. So I'm not really one to buy into the carbon neutral... whatever it is. Many people have likely had similar experiences here as well, and tend to agree. I know there are many detractors still here, but if there is a more valid argument against the global war... errrr climate change now right? I'd like to hear it.

Re:Oh brother... (0)

Anonymous Coward | more than 4 years ago | (#29033697)

thats the thing about AC, so dastardly one second, and then a thought provoking intellectual the next, thats why we all have a love hate relationship with AC.

Re:Oh brother... (1)

khayman80 (824400) | more than 4 years ago | (#29034329)

The human produced carbon is not causing a warming, and even if it was, admittedly we're talking about a 1/20th of a degree in change/preventive change. ... We would be much better off it seems if we cut back on water vapor... but then it might not rain as much... and don't clouds reflect light anyway?... Almost too many variables to account for, especially in a model that is inherently not stable.

Wrong. I got tired of repeating myself on Slashdot, so I wrote an article [dumbscientist.com] showing that abrupt climate change is a matter of serious concern.

That's a big goal ... (5, Informative)

MartinSchou (1360093) | more than 4 years ago | (#29033089)

One of my dorm friends, Jakob Husum [www.dtu.dk], wrote his dissertation [nt.ntnu.no] on ways of optimizing cement productions.

One of the rather impressive/scary things about that, is that it is responsible for about 2% of the world's energy consumption. That's an insane amount of energy for something that isn't even an end product.

The first paragraph of the paper actually grabs you by the balls and twists firmly:

Production of cement is one of the most energy
intensive industrial processes, consuming up to 2 % of the worlds electricity due to several low eciency processes. The grinding of cement clinker from the kiln is the most inefficient process in the manufacturing, with an efficiency of 1 % (Benzer et al., 2001).

Can't quite remember how much of the energy if spent on the last bit, but I think it was something like 25%. That's 0.5% of the world's energy usage spent on a 1% efficient process. Now imagine you could up the efficiency to 10% or even 5%. That'd be a reduction of the world's energy usage of 0.45 or 0.4% respectively, simply by improving a single process.

Now, there are a lot of arguments for saving energy. Saving the environment, less pollution etc., but it's hard to overlook the economic incentive of cutting back energy costs of a production, where a large part of the process is 1% efficient.

Nice thought, but.... (1)

WindBourne (631190) | more than 4 years ago | (#29033509)

what are the other costs for this new material? It is possible that this will take a lot more energy.

One odd idea for cement is to start using solar to make it. I would think it should be possible for using a solar kiln to do the heating of this. Yes, it will not solve the breaking up, but, the true energy intense part is the heating.

Green is the new Black (4, Insightful)

tengeta (1594989) | more than 4 years ago | (#29033165)

and by that phrase, I mean its popular bullshit. Most of the "green" things that have been devised over the past few years do NOTHING other than hold the carbon and make it the next generations problem instead. I thought the entire idea here was to NOT do that, but then again we live in an excessively hypocritical society that makes things up so they can make money, and this may just have been the latest and greatest. I'm not saying environmentalism is bad, but the majority of it so far isn't actually doing any good for the environment, its just helping the stock holders behind the products involved.

Re:Green is the new Black (2, Insightful)

Raptoer (984438) | more than 4 years ago | (#29033537)

I agree with you on the 'majority of it isn't actually doing any good' but I disagree on the hold carbon part. It's not like toxic waste where it's still a problem if something absorbs it. Carbon in the concrete isn't carbon in the air, and only carbon (dioxide) in the air is considered harmful to the environment. If it is in solid form (as calcium carbonate, or some other chemical, not as solid carbon dioxide) then it does nothing to the environment except sit, which it was doing before in the form of hydrocarbons (coal, gas, oil).

Ultimately a much better solution to the concrete problem would be to increase the efficiency of the production rather than change the end product to absorb carbon. As others have stated, not only is carbon release not the only problem with high energy use, but as this absorbs carbon what happens to its chemical structure? does it stay as strong as when it has finished curing? I can see it being used in applications where strength is unimportant like sidewalks, but no architect/civil engineer/ construction contractor worth anything is going to use an unproven concrete, just too risky.

Global Cooling On Its Way (0)

Anonymous Coward | more than 4 years ago | (#29033225)

Let's get something straight: The amount of carbon dioxide that's in the greenhouse gases is very fractional and the actual human contributed amount of CO2 is a small fraction of that. In fact, its dwarfed by rotting vegitation and animal releases of it. That, in turn, is even dwarfed by the amount of CO2 the oceans give off. So, what makes you green whackos think we have any impact on this? Well, unfortunately, we've entered a cooling off period. The Earth hasn't warmed since 1998 and actually slightly cooled off the last 2 years. On top of that, Farmer's Almanac, long a very trusted and reliable predictor of future events, has predicted a cooling of the Earth for the next 100 years. Which leads me to ask you environmentalists to PLEASE...STOP TRYING TO FIX THE EARTH! You're gonna screw it all up!!! Don't fool with Mother Nature!!!

Re:Global Cooling On Its Way (3, Insightful)

Nefarious Wheel (628136) | more than 4 years ago | (#29033301)

On top of that, Farmer's Almanac, long a very trusted and reliable predictor of future events, has predicted a cooling ...

It's good to see the Slashdot audience moving back to reliance on such scholarly peer-reviewed journals. That's science, that is, science by the quart.

Anecdotal (0)

Anonymous Coward | more than 4 years ago | (#29033615)

Take it for what it's worth, because obviously I can't prove this, but I asked friends a long time ago who work there, "how do you do this"? and this is what I got-> It is science, just published in their old ..almanac. And they nail it fairly well, too, over the years. It's bog standard normal how they do it, it's acceptable. They use accumulated data sets on the climate and weather and so on, all sorts of parameters, yes even including moon phases and so on, going way way back, and then model and do their yearly predictions from that. They don't just cast runes and use a Ouija board, it's not much different from what a lot of other teams do, except they don't use super computers, just normal old fashioned interpretation and analysis. They've taken observational data from a lot of sources over a very long period of time and specialized in future casting. Ya, it's posted "homespun", but that doesn't take away from all the work that went into it, and frankly, they seem just as good or even better than a lot of the overly bombastic climate and weather guessers out there now.

How about we just plant more trees? (1)

kc5deb (770159) | more than 4 years ago | (#29033267)

I swear... by the time this whole "green" fad is over, it'll be illegal to breathe....

finally (0)

Anonymous Coward | more than 4 years ago | (#29033345)

concrete results!

Most of the CO2 comes from calcination (4, Interesting)

wiredlogic (135348) | more than 4 years ago | (#29033595)

The summary doesn't explain things very well. Just to set things straight, most of the CO2 emissions from portland cement production is not from the fuel burned in the kilns but from the gas released by the limestone itself during the calcination process. The only real incentive for the use of energy efficient kilns is to reduce fuel costs and not to reduce emissions. The upside is that cement will reabsorb much of the released CO2 as it cures over the course of time.

Green pavement? (0)

Anonymous Coward | more than 4 years ago | (#29033667)

Won't that make it more difficult to see green traffic lights?

And if I don't put an emoticon here, you won't know I'm joking, so here: :P

Could cement plant be colocated with power plant? (2, Interesting)

JSBiff (87824) | more than 4 years ago | (#29033765)

"...mostly because cement, the active ingredient in concrete, is made by baking limestone and clay powders under intense heat that is generally produced by the burning of fossil fuels."

This sentence got me to wondering. . . one of the big problems of thermal electric power plants (coal, natural gas, nuclear), is that we throw away 50-60% of the heat as waste heat into the environment (nearby body of water or the air). Could the waste heat from a coal or nuclear power plant be used to 'bake' the cement? In the case of coal, sure, you're still burning fossil fuels, but those were being burned *anyhow* to generate electricity, so why not put the waste heat to use? You are, *at least*, not burning any *additional* fossil fuels just for the cement, right? In the case of Nuclear, you are using a very low-carbon heat source, and again, doing something useful with the waste heat?

Re:Could cement plant be colocated with power plan (3, Informative)

HornWumpus (783565) | more than 4 years ago | (#29034011)

It's not impossible but remember that (IIRC) theoretical optimum thermal efficiency is (THigh-Tlow)/THigh.

In practice that means that waste heat is generally too cold for this process. If it were hot enough to make cement it would be hot enough to extract power from.

Waste heat from Combustion Turbines (CTs) is already being used to generate steam in cogen plants.

'Pure' CTs are typically super-peaker plants. Lousy efficiency but they start and ramp fast. Which in practice means their heat is too unpredictable to run that kind of process in any case.

Typical applications of CoLo heating are greenhouses, malls and other large buildings. Market forces are making this (space heating) happen quite nicely where ever economically practical.

My university was/is entirely heated by the waste heat of the coal fired plant on campus (50+ year old setup). Good fun in the steam tunnels. Access to boiler rooms.

CO2 Absorbsion (4, Insightful)

matria (157464) | more than 4 years ago | (#29034075)

Why not just plant more trees around buildings made of concrete? That seems to me to be a more useful, long-term "incentive" program than some we've seen lately.

cost to future generations... (1)

benjamindees (441808) | more than 4 years ago | (#29034181)

I wonder whether any reduced lifetime or design flaws of new materials like these will be factored-in by those who implement them. There is obviously a lot of room for snake-oil salesmen to set up shop and exploit the world's move towards carbon-neutrality by over-promising on products that would normally last for decades. It would be a very-bad-thing if the shortcomings of more environmentally-friendly products were not priced-in from the outset.

But it would be even more destructive if the move towards environmentally-friendly products and processes turned out to be an extension of the "designed obsolescence" movement of recent past. Cement has a fatal flaw as a product: it lasts a long time. Perhaps an entire lifetime, or more. Bridges and roads last a long time. Houses don't have to be re-built every generation. Mortgages expire. Producers, sellers and governments hate products like this. Producers want to keep producing forever, as long as they don't have too much competition. Sellers want to keep selling forever, earning a tidy profit. Governments don't handle inter-generational wealth transfer well. So-called "consumers" hate long-lasting products too. They constantly want new stuff to replace their old stuff. They want jobs making that new stuff. Sheeple appreciate the stability of going to work every day to get paid less and less, just as long as they are boiled slowly and can pass most of the buck to future generations.

Self-destructing concrete, if more environmentally friendly than the regular kind, could even be government-mandated. Construction jobs would go on forever! Recessions would be a thing of the past! Cyclical fluctuations in the economy would be replaced with one big perma-recession. We could all hold hands and join in one big suicide pact for humanity, that wouldn't come due until all the the easily available energy and mineral resources run out and we're already dead and buried.

People keep talking about the cost to future generations of carbon emissions, caps and taxes. But how does that occur, exactly? It's clear how carbon emissions might affect future inhabitants of Earth. The CO2 will be there in the atmosphere, heating the globe, affecting the Earth. There is debate as to what those effects may be, but it's clear how it occurs. But how do caps and taxes affect future inhabitants? Well there's the lost opportunity-cost of all the cool stuff we could have bought instead of investing in green technologies. We could have more stereos and TVs and bigger houses with copper roofs and stainless appliances. Or we can forego some of that and have renewable energy instead. We can make do with smaller TVs and fewer stereos and smaller houses with tin roofs and less-fancy appliances. And I think many people would choose to do that if given the choice. The choice is fairly straightforward.

But it's an even larger problem when the choice is not so clear. If people are told that they can have the same amenities and live the same lifestyle while also making gains in CO2 emissions, something doesn't add up. If green products come out that make grand promises of equivalence with existing, less green products, consumers will likely believe them. If, or when, those new products fail to live up to the expectations, there is potential for huge economic losses. It is one thing to make a decision to curtail consumption in exchange for a more green, renewable world. It is quite another to trade an existing lifestyle for some crapshoot on vague promises or outright fraud, brought to you by corporations that are only interested in next quarter's profits and governments that are only interested in paying off their cronies before their term expires.

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