Industrial Waste Can Turn Planet-Warming Carbon Dioxide Into Stone (sciencemag.org) 77
sciencehabit writes: Every year, mining and industrial activity generates billions of tons of slurries, gravel, and other wastes that have a high pH. These alkaline wastes, which sit either behind fragile dams or heaped in massive piles, present a threat to people and ecosystems. But alkaline wastes could also help the world avert climate disaster. Reacting these wastes with carbon dioxide (CO2) from the air converts gaseous carbon into minerals and neutralizes the wastes' alkalinity. Carrying this out on a global scale could trap between 310 million to 4 billion tons of CO2 annually, according to recent surveys. That could provide the world with a much needed means of lowering atmospheric CO2. But there are major hurdles. Governments will need to offer incentives for mineralization on the massive scale needed to make a dent in atmospheric carbon. And engineers will need to figure out how to harness the wastes while preventing the release of heavy metals and radioactivity locked in the material.
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Re: Slashdot can turn stoned BizX people into? (Score:1, Flamebait)
I think I know that tune (Score:3, Insightful)
it's not a practical option. (Score:4, Informative)
You have to transport the alkaline industrial waste to where the carbon dioxide is, or the other way around. Lorries, trains, so extra carbon dioxide is used to bring the ingredients together. An industrial plant must be built where the waste and CO2 are combined, using concrete, creating more pollution. So finally you have the CO2 trapped in a mineral rock form, which must be taken away and buried, again more transport and waste.
So the idea is lovely, but it's not practical in real life except in a few edge cases. Sorry!
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building those roads will be disruptive and add CO2 to the atmosphere.
It can be done by robots with solar panels and wind turbines on their heads.
Once you get to having a solar powered solar panel factory then it's turtles all the way down.
Re: it's not a practical option. (Score:5, Interesting)
Edge case uses, only.
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Part of the problem is the scale of the problem.
Assume this is cheap and works perfectly, and can immediately start sequestering 4 billion tons of CO2 annually. That's still only 10% of the global emissions from fossil fuels. Still worth doing, especially if it's neutralizing other toxic waste at the same time - but you'd stop hearing about it almost immediately as it becomes just one of the many things we do to reduce the rate at which the problem is getting worse. When's the last time you heard anythin
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There are lots of solutions that certainly work. We're just waiting for someone to step forward and foot the bill for one of them.
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It can be done if you start irrigating deserts, just need cheap efficient desalination and that is already out as well as the way to make it economically profitable, beyond just environmentally possible. So they could start working on it now but they will not, greed tied to existing fossil fuel sectors of the economy block it as well as the general lack of intelligence at the top. The reward of nepotism, incompetence at the top. They could actually start to tackle climate change in a profitable way and they
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Re: One Day (Score:1)
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Many days (Score:1)
But hey, I like trees too. And it can be a part of the solution.
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The main problem is land use.
Too much of the world has been deforested for agriculture.
We need to modernize agriculture to be less land intensive (food factories?). Then there will be room for nature again.
Carbon sequestration is a bandaid. Agriculture is the problem.
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Notice that parts of the world have problems with malnutrition. And having grains instead of milk is not a solution for it.
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It's being worked on - mostly in places like Japan where land is expensive enough that building farms in skyscrapers makes some sense - and where they now have some lovely irradiated land that's pretty much useless for anything other than sealed greenhouses.
Basically - agriculture is a low-margin business, to the point that even plastic-sheet hoop-house greenhouses are really only viable for more profitable crops. The elaborate greenhouses needed for vertical farming just can't compete economically, which
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Vertical agriculture assumes pre-existing vertical structures to which plant-growing fixtures are added. Those vertical structures imply densely populated areas, which have been recently shown to help spread disease.
Furthermore, vertical agriculture does not increase net solar flux available to plants, because vertical structures cast shadows -- shadows are areas without solar flux. Horizontal surfaces that we call "ground" are more economical.
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At the risk of being dismissed as a loony vegan, I think agriculture to feed animals is the problem. To put it bluntly, people eat too much meat. Beef used to be a luxury food, that reasonably well-off people could eat once a week, in their Sunday roast. Now beef is something anybody can eat any time. As far as I know, most soya is used for animal feed. Soya is actually a particularly good source of protein for people to eat, though traditionally a fair bit of processing such as fermentation is needed to ma
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It certainly is, especially if you're talking beef, which is one of the most inefficient sources of meat, requiring about 6-25lbs of feed to produce 1lb of meat. Pork is a lot better, at ~4-9lbs of feed, and chicken even better at 2-5lbs of feed. That's still pretty inefficient though - especially since chickens can only eat grain, unlike pigs and cows that can eat the leaves and stalks as well. (In fact that's probably a big reason why herding became a thing in the first place - cows, etc. can turn inedib
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It is indeed true that most animals we kill and eat for food traditionally live on foods like grass, which humans cannot eat, because we do not have the right kind of guts. But I think pure grass feed cow is something of a rarity nowadays; strictly for the rich foodies. And I was told by a farmer that it is now illegal to feed scraps from the kitchen or restaurant to pigs, for fear of spreading diseases.
I guess I have been a vegetarian for so long that I do not want my food to taste like meat. However, I am
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Yeah - lots of things changed for the worse as we industrialized farming rather than eating what we raised ourselves.
I can certainly understand having lost a taste for meat - I quite love good vegetarian cooking. I also love meat though, as well as the environment and avoiding animal cruelty. So I heartily approve of new techniques to capture the experience of eating meat without the ethical or environmental price.
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So what would you suggest? Some kind of mass starvation that make Mao's "great leap forward" look like a humanitarian success?
We have all that agriculture land because 8 billion people need to eat. Sure, we could probably use less by changing dietary balances away from meat and just directly eating it ourselves rather than letting cows pre-process it, but good luck implementing that globally when you can't even convince people to wear a fucking facemask in the middle of a pandemic.
Agriculture alternative (Score:2)
One compelling alternative to agriculture is microbial farming - NASA did a bunch of research decades ago on growing food from hydrogen-fed microbes, which some company is now looking to commercialize here on Earth.
Especially when half the stuff sold at the grocery store is heavily processed, the ability to produce alternatives to such staple ingredients as palm oil, flour, sugar, and protein powder in huge vats, whose crop takes days to grow rather than months, promises to be a huge asset. Especially given
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Store it in closed mines. Turn it into PLP for use in construction. Just don't burn it.
But first it needs to grow. And to grow it needs land. Right now, deforestation is still rampant around the world. Reforestation cannot compete, there is no will, and vested moneyed interests in the land that it would use are blocking it. A lot of the UK should be temperate rainforest, but sheep farming, grouse moors for toffs to shoot guns, and so on, keep the land bare.
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Why would it have to be trees? Couldn't you grow something like bamboo and then just bury the resulting product after harvesting? This would have a side benefit that in ~1 million years we would have another source of crude oil to start the process all over again. 8^)
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2) Burying requires energy to do that burying, and yet it does not prevent decay of the buried material.
Growing plants is a good thing, though it is not a solution per se.
There is an amount of methods [wikipedia.org] (in development).
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I do not know what you mean about storing wood for a long time. Don't trees do that anyway, while they are growing?
Cultivating fast-growing trees as biofuel might look attractive: grow your own coal. But I have read that biofuel plantations can displace natural forest or local farming. If what you want is biofuel, then I think there are organisms other than trees that will provide this, with less disruption to the natural or social environment.
Wood is a useful construction material. I believe wood-framed hi
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If only there was a way we could use solar power to turn CO2 into wood on a massive scale. Crazy I know. A man can dream.
Clearly throwing some shade here.
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Energy? (Score:2)
And how much energy does this process take?
A lot I bet. But does anyone know?
Re:Energy? (Score:4, Insightful)
That being said there's probably an issue of how to ensure the substances react appropriately on a large scale. In places where both CO2 and these wastes are produced is idea, as there's no real issue with transportation- just capture and the circumstances around a controlled reaction. Otherwise the transport of either CO2 or waste material might render the overall gain null and void.
The actual reaction has to take place in an appropriately controlled environment, but we definitely have the technology to do it. The question then remains what will encourage use of this method? What monetary gain is there to be had in eliminating these waste products when there's little consequence for companies to dump the waste cheaply or just release the CO2 produced?
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The reaction of CO2 with alkali should not require energy input; it might actually generate energy. I think the practical problem is that atmospheric CO2 is very diffuse, so how do you get enough of it into the slurry? We could have the likes of sewage aeration tanks, which are like massive food processors stirring the stuff to feed the bacteria, but these stirrers take energy to operate. As people have said, mining waste tends to have high concentrations of pollutants such as heavy metals, so even if we co
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We have enough energy. The problem is the side effects [youtube.com].
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We refill pressurized CO2 tanks from coal plants already. Basically CO2 is already shit we have lying around in high concentrations.
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And how much energy does this process take?
A lot I bet. But does anyone know?
Who cares if it can be powered by renewable energy sources?
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> Who cares if it can be powered by renewable energy sources?
If this carbon sequestering process consumes significant energy from non-renewable resources, then I would suggest that it is a non-starter. Why bother? For various reasons, I suspect that net energy input is required to react alkaline slurry with atmospheric CO2. This might have some environmental benefits, but only if the process does not generate more CO2 than it consumes.
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If this carbon sequestering process consumes significant energy from non-renewable resources, then I would suggest that it is a non-starter.
It's a non-starter anyway. Nobody's going to bother putting enough effort into logistics and infrastructure to make this work, there's no quick profit in it (if any at all).
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I agree that it probably makes no economic sense, so it will not happen.
But what is going to happen to all these slag heaps and tailings lagoons? They do not just go away on their own. As things are now, a mine can operate for a number of years, create loads of waste, then the miners go away, with no obligation to tidy up. I am not sure how you tidy up a lagoon of heavily polluted slurry. Perhaps CO2 processing might help. Obviously, I am talking about government interference in the free market here, to mak
Obligatory (Score:3, Funny)
Total Need (Score:2)
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Well that was stupid. All you had to do was say something like, "hey let's impose environmental disposal fees for mineral alkaline industrial waste that we can waive in the event that the producer instead opts to ship their waste to a CO2 processing facility". Or you know, something vaguely rational like that. Assuming there aren't already disposal fees associated with these slurries.
But no instead you had to accuse someone of psychopathic crimes or whatever. And that sort of thing is why serious work d
Economic viabillty (Score:1)
Carbon sequestration, meaning chemically extracting atmospheric CO2 and turning it into a storable form, has to be paid for. It might make it cheaper if there is a ready source of alkaline material in mine tailings, but I do not think carbon sequestration will be a profitable business. I do not think mining companies, that produce vast lagoons of slurry, should pay for this processing, because they were probably not responsible for the CO2 emissions we want to sequester.
The trouble is, who pays for this? Th
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Remember that those mining companies ARE responsible for producing vast lagoons of slurry.
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I agree that the mining companies are responsible for the vast lagoons of slurry. But they are not responsible for all of the CO2 emissions, which might possibly be reduced by using these lagoons as a resource.
I once stumbled into a slurry swamp while out walking in Scotland. I think it might have been related to aluminium ore processing. The mud was brick red, and it took a lot of effort to clean my clothes and shoes when I got home. Goodness knows how long that swamp had been there. Enough time for trees
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So the slurry can be declared an environmental hazard, and the producers can have their pockets picked to pay for sequestration if necessary. Taxation, fees, and fines aren't always about who's responsible. Sometimes it's just about getting your hands into someone's pockets.
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This is all very well, but if only some miners have their pockets picked, they are then at a disadvantage relative to miners not subject to financial penalties. So what we end up doing is outsourcing polluting industries. I am pretty sure this is already happening.
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Ahhh now you are catching on.
Because if it were CO2 that were actually declared "the problem" (and this has gone to court in the United States before, with no positive results for the plaintiffs), then everyone would be held responsible and everyone would be taxed, even if a few repeated offenders were the ones responsible for the majority of atmospheric CO2 increases.
Even if you somehow got your own domestic CO2 emissions down to 0, that doesn't cover countries like China that answer to no one else. So wh
captain obvious to the rescue (Score:2)
so mixing a acid (co2) with a base (alkali waste) will cause a chemical reaction... producing stone ... hummm.. maybe if you consider salt a stone.
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You may not end up with a useful structural material, like stone or concrete. But the solidified material might be a useful filler for concrete, or foundations for roads, or whatever. This is surely better than just burying the stuff, to no productive purpose.
Thieves and Liars (Score:2)
Every year, mining and industrial activity generates billions of tons of slurries, gravel, and other wastes that have a high pH. These alkaline wastes, which sit either behind fragile dams or heaped in massive piles, present a threat to people and ecosystems. [...] Governments will need to offer incentives for mineralization on the massive scale needed to make a dent in atmospheric carbon.
So in summary, industry is producing harmful wastes, and they want us to pay for them to clean it up, when all they have to do is push CO2 through those wastes which they could do using exhaust from a NG plant, making both industries cleaner. But because we don't make them pay for their externalities, it's cheaper for them to just leave the wastes lying around unless we give them money to reward them for pollution.
How about instead of incentives, we disincentivize pollution with taxation, and let the so-cal
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I do not like these slag piles and slurry lagoons, but unless all miners throughout the world are taxed to clean up these externalities, the companies that are not taxed will prosper at the expense of the companies that are taxed, which is surely not the intended outcome. There is a general tendency for "dirty" industries to be outsourced, so we still get our cheap stuff, but some other folks far away deal with the shit. No amount of national taxation is going to deal with that problem. It might even make i
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Actually, there is: import duties. Levied squarely and fairly based on the externalities involved. Maybe do that for labour practices too.
Of course, that means us in the West get to pay more for our cheap tchotkes, so we can't fill our houses with junk anymore. And we can't have that. What are you, some sort of dirty commie?
Hi...I was a really (Score:1)
How much energy does it take? Where's it from? (Score:2)
The process apparently involves both concentrating atmospheric carbon dioxide and pumping large amounts of liquid around. That takes energy. How much does it take, and where does it come from?
If you use electric power generated by fossil fuels, you generate more carbon dioxide. Do you get ahead or fall behind?
Even if practical, this might require energy input from a non-carbon-emitting source to be worthwhile - and will do better in the carbon capture department even if it still works with fossil fuels.
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Yes, this looks like a technologist's solution. There is already a carbon sequestering solution that requires very little energy input: grow more trees. Photosynthesis is the most amazing chemistry. You actually end up making something useful out of a waste product. And solar energy is converted into useful stuff, instead of just heating the earth. There are other photosynthesis opportunities, such as seaweed farms.