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Earth Science

Spreading Rock Dust On Fields Could Remove Vast Amounts of CO2 From Air (theguardian.com) 149

Spreading rock dust on farmland could suck billions of tons of carbon dioxide from the air every year, according to the first detailed global analysis of the technique. The Guardian reports: The chemical reactions that degrade the rock particles lock the greenhouse gas into carbonates within months, and some scientists say this approach may be the best near-term way of removing CO2 from the atmosphere. The rock dust approach, called enhanced rock weathering (ERW), has several advantages, the researchers say. First, many farmers already add limestone dust to soils to reduce acidification, and adding other rock dust improves fertility and crop yields, meaning application could be routine and desirable.

Basalt is the best rock for capturing CO2, and many mines already produce dust as a byproduct, so stockpiles already exist. The researchers also found that the world's biggest polluters, China, the U.S. and India, have the greatest potential for ERW, as they have large areas of cropland and relatively warm weather, which speeds up the chemical reactions. The analysis, published in the journal Nature, estimates that treating about half of farmland could capture 2 billion tons of CO2 each year, equivalent to the combined emissions of Germany and Japan. The cost depends on local labor rates and varies from $80 per ton in India to $160 in the U.S., and is in line with the $100-150 carbon price forecast by the World Bank for 2050, the date by which emissions must reach net zero to avoid catastrophic climate breakdown.

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Spreading Rock Dust On Fields Could Remove Vast Amounts of CO2 From Air

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  • by Anonymous Coward

    ...removes CO2? Trees. Plants. And these organisms can produce tasty fruits, berries, and veggies. Rocks...not so much.

    • ...removes CO2? Trees. Plants. And these organisms can produce tasty fruits, berries, and veggies. Rocks...not so much.

      You know which one costs 1,000 times more to execute and maintain?

      Now you know why we're planting rocks.

      • by Freischutz ( 4776131 ) on Thursday July 09, 2020 @07:15AM (#60278482)

        ...removes CO2? Trees. Plants. And these organisms can produce tasty fruits, berries, and veggies. Rocks...not so much.

        You know which one costs 1,000 times more to execute and maintain?

        Now you know why we're planting rocks.

        Some of the most effective carbon sinks are wild forests and they sort of tend to maintain themselves once re-foresting efforts reach a certain point. Given the choice I'd pick re-planting wild forests any day of the week over abandoning re-foresting efforts and going all out for rock dust all on its own because lobiusmoop on Slashdot says so without citing any proof. However, if pulverised rock does help improve soil quality in some way and the carbon footprint of pulverising rock does not outweigh the benefits as a carbon sink I don't mind people using it. The point here is that showing up in a puff of smoke like you did and yelling at people for suggesting that planting trees might be a good idea is an act that in it self does nothing but make you look stupid, especially because TFA which you obviously didn't read says, and I quote:

        “Planting trees is an excellent option for CO2 removal but is not sufficient on its own,” said the scientists. [Because of the sheer quantity of CO2 already in the atmosphere and the time frame in which it needs to be removed, i.e. by 2050]

        Basalt is preferred for ERW as it contains the calcium and magnesium needed to capture CO2, as well as silica and nutrients such as potassium and iron, which are often deficient in intensively farmed soils.

        Some farmers in south-east Asia already use it to boost depleted silica in rice fields, while trials in the Netherlands are using it [Enhanced Rock Weathering, ERW] to boost tree planting. Most importantly, ERW reduces soil acidity, which already affects about 20% of arable fields around the world.

        • by Junta ( 36770 ) on Thursday July 09, 2020 @07:31AM (#60278534)

          carbon footprint of pulverising rock

          Note that they suggest that adequate quantities of basalt dust are a byproduct of existing mining operations. One could make the argument that the mining operations have a negative footprint in general, but so long as the operations are happening anyway, if any byproduct can help mitigate things that sounds reasonable enough.

        • by tsqr ( 808554 )

          Given the choice I'd pick re-planting wild forests any day of the week over abandoning re-foresting efforts and going all out for rock dust all on its own because lobiusmoop on Slashdot says so without citing any proof.

          Nobody's talking about "abandoning re-foresting efforts", as far as I can see. Go ahead and re-plant all the wild forests you want, or encourage others to do it; I bet lobiusmoop wouldn't care, one way or the other. The proposal under discussion here is about spreading rock dust on farmland. My guess is that the farmers would not favor planting forests on their farms, but who knows -- you might be able to talk them into it.

        • by PPH ( 736903 )

          Some of the most effective carbon sinks are wild forests

          Not really. Once they reach maturity, the rate of vegetation dying is balanced by the rate of its growth. And that dying represents CO2 being exhaled by the organisms rotting it. Otherwise our old growth forests would have amassed a carbon rich layer that has been increasing since the end of the last ice age. They don't. I can get through the top soil in a forest with a hand shovel.

          The only credit a forest should get for sequestering carbon is the number of tons per year that can be hauled out on logging t

    • by ArsenneLupin ( 766289 ) on Thursday July 09, 2020 @05:54AM (#60278380)

      ...removes CO2? Trees. Plants.

      Correct.

      And these organisms can produce tasty fruits, berries, and veggies.

      Tasty? As soon as you eat those organisms, you free up that CO2 again.

      And if these veggies happen to be beans, you might release something far worse for the climate [sciencedaily.com]...

      • by e3m4n ( 947977 )

        it seems obvious then, we need to start making more graphite, diamonds, nanotubes, and graphene. Get those nano-assemblers working on diamond and nanotube building materials instead of pine. Thats one way to permanently lock away the carbon.

      • Tasty? As soon as you eat those organisms, you free up that CO2 again.

        Not quite. You free up the carbon that was in the part of the plant that you ate. The rest of the plant (usually the roots) is still in the soil, made up of carbon. Also, the process of plants growing deposits carbon into the soil. So no, growing crops and harvesting them and eating them is not a net zero gain of sequestered carbon.
    • by U0K ( 6195040 ) on Thursday July 09, 2020 @06:47AM (#60278436)
      The good old false dichotomy again.

      Yes, it removes CO2.
      If you spread it on the fields it will mostly reduce part the CO2 that is emitted from decomposition of bio matter the soil.
      That doesn't mean there won't be enough atmospheric CO2 left for the plants. That's the CO2 that matters most to plants, because photosynthesis, the process that involves splitting CO2 with the energy from sunlight, happens where cells containing chloroplasts are exposed to sunlight. Or maybe more specifically an energy source that emits EM radiation in the wavelengths that chlorophyll absorbs efficiently. And that usually happens to be the case for above the ground parts of the plant that are exposed to sunlight or other light sources that cover that spectrum.
    • The problem is not only how to remove CO2 from the atmosphere, but also how to keep it away from it. Plants are excellent at removing CO2, but then you must keep the CO2 fixed, either by leaving the plants in place, or by converting the mass to a more stable form. So, plants or algae would work, but you'd have to take your crops and bury them under a clay layer so that maybe in a few million years you'll have a new layer of crude oil. It's a bit of a hard sell.

      • Freeman Dyson in 76 made an early calculation for what an emergency project would involve for capturing carbon with plants, and later followed it up with ideas on building up top soil to fix CO2, the point being that you don't just capture carbon in the short run but keep it captured.
        I like the ideas very much but they are quite tricky. The CO2 often wants to get out again. You also can't count on them to be a sufficient approach by themselves.

      • by skam240 ( 789197 ) on Thursday July 09, 2020 @08:18AM (#60278696)

        I don't follow what you're saying. As far as my understanding goes, with food crops we eat the good parts and poop out the remains. Sure, some of the CO2 gets freed up during this process but there's still plenty in our crap which then basically devolves into dirt. The left over bits from the food crops that we don't eat are then disposed of and decompose (assuming they aren't burnt. that would free up all of the carbon) which again would free up a bit of CO2 but the rest would devolve into basically dirt. In both cases CO2 is indeed "trapped".

        Not claiming any expertise here mind you, that's just how I understand such systems work. Plus, I mean, I would certainly hope the scientists who wrote the paper this is based on and those who peer reviewed it (all of whom quite likely have far more expertise on this subject than either of us) wouldn't miss such a truly glaring error.

        • Respiration in humans takes oxygen and combines it with sugars from the plant and produces energy and CO2. We also produce some methane in the digestion process but it's fairly negligible. Humans are pretty inefficient at this so some of the waste will be useful sugars (thereby locking up some of the carbon) but the whole point of digestion is to extract that stuff for use in the body. Once it is eliminated, it is further eaten by bacteria and other creatures in the environment who also emit CO2 and meth

        • We need to do more than just trap CO2 in the soil. We've been pumping and mining large amounts of CO2 from deep underground and releasing it into the atmosphere for decades, and simply putting what little of it we can into the soil keeps it in the carbon cycle.

          In the long term, we need to find a way to take CO2 back out of the carbon cycle. Make it inert like it was before the industrial revolution. Sequester it. Maybe we dig some really deep holes, fill them with trees, then cap the holes to keep oxygen ou

    • by Junta ( 36770 )

      Keep in mind they are saying this as an added part of how active farmland is treated. I presume basalt dust is considered at least a safe thing to add to farmland without reducing crop production.

      To give up farmland to plant forest would be a much tougher sale than 'oh, use some basalt dust on your fields'

    • It is much harder than that.
      Do you want people to knock over your home to plant trees. Or force relocate you to the Desert. Yes this is the most extreame case however where we live and thrive is also in conflict where trees live and thrive.
      While our forests should be protected against expansion especially unneeded expansion, and areas that are no longer being utilized should be reforested.
      However you are not going to plant too many trees in the Mid West US where it is mostly planes and deserts. Also for y

    • by hey! ( 33014 )

      ... and then your use of those plants (or just their decay) releases the CO2 back into the atmosphere. Capturing carbon this way does *not* sequester it except for a very short time.

      Replacing a fossil fuel use with a renewable plant-based process *does* reduce the amount of CO2 in the atmosphere (e.g. biomass fuels), but you can't *offset* a ton of carbon you're emitting from fossil fuels by growing more plants, unless you lock away those plants somewhere.

      Ocean fertilization works this way. You take a p

    • "Not so much"? Rocks can (and do!) remove much more CO2 from the atmosphere than trees can. The only issue is, they do so at geological time scales.
    • 1) Trees take far longer to grow and suck up CO2. This process takes months.

      2) This isn't an either/or situation. Both can be done.

  • by sTERNKERN ( 1290626 ) on Thursday July 09, 2020 @05:26AM (#60278346)
    Any solution which does not take the big picture into consideration is just a fancy way to shoot ourselves in the foot, again and again. We need a way for complete recycling, otherwise we just generate another issue for later generations.
    • by bobstreo ( 1320787 ) on Thursday July 09, 2020 @05:28AM (#60278354)

      Any solution which does not take the big picture into consideration is just a fancy way to shoot ourselves in the foot, again and again.
      We need a way for complete recycling, otherwise we just generate another issue for later generations.

      I guess it all depends on how many people you recycle.

      • Any solution which does not take the big picture into consideration is just a fancy way to shoot ourselves in the foot, again and again. We need a way for complete recycling, otherwise we just generate another issue for later generations.

        I guess it all depends on how many people you recycle.

        Let's just make Soylent Green.

    • by Junta ( 36770 )

      Those would seem to be orthogonal problems to solve. Carbon sequestration versus consuming non-renewable resources. I'm sure there are people working toward your cited problem as well, but there are enough of us to work on more than one problem at a time.

  • Ouroboros (Score:5, Insightful)

    by pjt33 ( 739471 ) on Thursday July 09, 2020 @05:28AM (#60278356)

    First, many farmers already add limestone dust to soils to reduce acidification

    So farmers add carbonates to fields in order that they react with acids, liberating CO2, and the proposal is that in addition they should add rocks which react with CO2 to form carbonates. Something about this idea seems off: it seems that it should be either counterproductive or energetically unfavourable. Am I missing something?

    • Re: (Score:2, Interesting)

      by AmiMoJo ( 196126 )

      You are missing that it's all a question of cost. Spreading limestone improves yields, i.e. reduces cost. But if we just pay them more than the limestone yields to spread something else they will.

      Industries that produce CO2 will be willing to pay to offset their emissions with capture. Eventually they will have to if we are to reach net zero.

      • You are missing that it's all a question of cost. Spreading limestone improves yields, i.e. reduces cost. But if we just pay them more than the limestone yields to spread something else they will.

        So, a significant increase in food costs is what this comes down to? Yeah, that'll help everyone. Nothing like a famine to get people to focus on climate change, right?

        • by hey! ( 33014 )

          No, because if you're paying farmers it offsets their costs. It will increase gasoline and other fossil fuel prices because presumably that's where we'll get the money.

    • Re:Ouroboros (Score:5, Interesting)

      by Solandri ( 704621 ) on Thursday July 09, 2020 @06:25AM (#60278410)
      That basalt can absorb CO2 [eos.org] has been known for a while [nature.com]. In a nutshell, when they first tested sequestering CO2 deep underground, and measured it months later, they found the amounts of CO2 were much lower than expected. Further research turned up that the basalt itself was mineralizing it. They knew that would happen, but it was happening a lot quicker than expected.

      Unfortunately, the anti-global warming movement is comprised of several different factions. Some just want to stop global warming. Others (including many in the media) have an anti-oil agenda. So you may not have heard as much about this phenomenon as you should have, since it provides a potential solution without having to give up fossil fuels.

      Facilitating the process above ground is something I hadn't heard of. I had thought the high pressures underground were a necessary component in the process. Without having read TFA, I'd hazard a guess that the pressure requirement is being obviated by greatly increasing the basalt's surface area by grinding it into powder. I'd be curious what the energy requirement of that is. And as you mention, the other problem with doing it above ground is that the resulting limestone can be converted back into CO2 [bgs.ac.uk] in the presence of acid rain. If you do it miles underground, it's stuck down there permanently.

      The limestone acts more like a buffer, not as a base, preventing the acid from changing the pH until the limestone has all been used up. Not by turning the land basic so acid rain can't lower its pH below 7. So I doubt all the limestone would be converted back into CO2. If that were the case, there would be no more limestone left near the surface. It just means we would have to be more careful about preventing SO2 emissions (which cause acid rain).
      • Re:Ouroboros (Score:5, Informative)

        by RockDoctor ( 15477 ) on Thursday July 09, 2020 @08:10AM (#60278668) Journal

        Facilitating the process above ground is something I hadn't heard of. I had thought the high pressures underground were a necessary component in the process.

        It's nothing new as an idea. A decade, if not two, since I first saw people working out how much would be needed globally to offset current CO2 production and start reducing atmospheric levels and having an effect on the climate. Plus accounting for the transport of the basalt (lump or powder).

        Without having read TFA, I'd hazard a guess that

        Where do you think this is? Slashdot?

        the pressure requirement is being obviated by greatly increasing the basalt's surface area by grinding it into powder.

        Increased surface area increases the actual rate of the reaction, if not the rate at the molecular level. The reaction happening is the same as happens in weathering the surface of a cliff, but you make more surface area for the reaction to occur.

        I'd be curious what the energy requirement of that is.

        Fair question. It has been part of the discussion about this geoengineering technique for several decades. Which you wouldn't know, not having RTFA. Have you counted how much time you saved by not RingTFA compared to these exchanges? Might be worth doing that calculation. (See also my repeated assertions that reading journalist's write ups is a waste of time compared to reading the actual published papers - same argument.)

        You also need to account for the energetic cost of moving the basalt (lump or powder) from the quarry to the plains where you're going to be spreading it, dispersing it over the land, etc. In Britain, where the Grauniad is based, basalt is mostly in the far NW islands, while the agricultural land (where the minerals certainly wouldn't hurt the soil fertility) is concentrated to the SE. That's about the worst distribution, and you'd need to make the redistribution efficient - trains, not trucks - to maximise the effect. But it's probably beneficial, even in this worst case.

        And as you mention, the other problem with doing it above ground is that the resulting limestone can be converted back into CO2 in the presence of acid rain.

        Stop producing acid rain. Simples. Much of European industry has done this already - as far as point-source sulphuric acid goes. Dispersed sulphuric acid - from vehicle exhausts - is precisely why the production of diesel oil involves removal of sulphur compounds at the refinery. (If it's in a train wagon on the way to landfill or another chemical plant, then it's not acid rain.) Because sulphur-containing diesel is labelled at the station pump, and has the social cachet of wearing a fresh, bleeding seal cub stole on the Oscars red carpet, most refineries have been desulphuring their product as the equipment comes down for maintenance.
        The remaining problems from acid rain are largely nitric acid (see - lean burn engines) and the irrelevant carbon dioxide. (It is irrelevant in an "acid rain releases CO2 from carbonates" discussion because one molecule goes in for each molecule that comes out.)

        We have completely adequate reasons for not producing acid rain which are orthogonal to the climate effects of CO2.

      • by e3m4n ( 947977 )

        why wouldnt you want the ph below 7? most plants thrive where the ph is between 5.5 and 6.5 resulting in the highest nutrient absorption. Below 5 and above 7.5 and the plant finds itself in nutrient lockout.

      • Re:Ouroboros (Score:4, Interesting)

        by Mspangler ( 770054 ) on Thursday July 09, 2020 @08:50AM (#60278792)

        As far as the energy required to grind rock to powder, look up the Bond Work Index. Also be aware that size reduction is about 2% efficient. It's a big part of the cost of mineral processing.

        Overall, natural weathering of the Rocky Mountains and the Himalayas are what brought the CO2 levels down from the mid-Pliocene levels to low enough to let the ice age start, so be careful what you wish for.

      • 1. Fraking is destroying ground water while the American Southwest is running out of the stuff.

        2. We're venting Helium off into the atmosphere to get at cheap natural gas. HE is used in all modern electronics and when we run out we're well and truly fucked.

        3. We're heavily dependent on Mid East nations for oil supply, yes even though we produce enough for ourselves remember that if they stop producing the price skyrockets and the oil we produce will be sold overseas for higher profits, driving up th
      • by ceoyoyo ( 59147 )

        Natural rock weathering is one of the main carbon sinks on the planet, along with sequestration of organic matter on the ocean floor. It's why our volcanoes didn't turn us into Venus long before people came along.

    • by ceoyoyo ( 59147 )

      Chemistry?

      Rain (H2O) absorbs CO2 on it's way down, forming some carbonic acid (H2CO3). This reacts with the limestone (CaCO3) to form calcium bicarbonate [Ca(HCO3)2]. The CO2 goes into the *bi*carbonate, not back into the atmosphere.

      Basalt appears to chemically weather through a process where it releasts Ca, which then binds with CO2 (and oxygen) to form CaCO3, and then you're at the start of part 1.

  • Limestone? (Score:4, Informative)

    by Viol8 ( 599362 ) on Thursday July 09, 2020 @05:32AM (#60278362) Homepage

    Not sure if the author was implying limestone spread by farmers would do the job but it most certainly won't. In fact quite the opposite - its slowly dissolved by the mild acid in rainwater and is converted back to calcium oxide and CO2.

    As for other rock types , as usual it will only work if the CO2 generated in producing and transporting the dust is less than the amount of CO2 is absords. I'm not convinced the difference will be significant or even +ve.

    • The Nature article references this, in terms of reduced efficacy. It also mentions that the reason why limestone is used is that intensive farming leads to the acidification of the soil. As to the cost of the techniques- they are also discussed in the environmental economics model. If you don't have access to Nature, I suspect you can get to the article via sci-hub.

      • by Viol8 ( 599362 )

        Odd, I'd have thought that ammonium based fertilizers would have made the soil more alkaline. Shows what I know about farming :)

      • Does it explain why powdered limestone and other rock reduces CO2 when on fields and increases it if you're making cement? It can't be the heating, as the article mentions, "relatively warm weather, which speeds up the chemical reactions".
        • by robbak ( 775424 )

          The poster above has misread the article.

          The article notes that spreading rock dust on fields is already done - they spread limestone to reduce soil acidity. But limestone doesn't capture carbon - as others stated, it releases it.

          The suggestion here is that we (also or instead) spread igneous rocket dust - basalt or granite. When these rocks break down, they do absorb carbon from the air, creating carbonates in the soil, as well as lots of other minerals, and more topsoil, too.

        • by Viol8 ( 599362 )

          Youre confusing limestone with lime. Limestone isn't used in cement directly , its converted to calcium oxide (lime) first by heating which releases huge amounts of CO2

    • by RockDoctor ( 15477 ) on Thursday July 09, 2020 @08:19AM (#60278704) Journal
      The article is about spreading basalt (an igneous rock) dust, not limestone.

      The energy emissions in mining, grinding and transporting many tonnes of basalt are a significant part of the equation. You need to be as efficient as possible in those steps, but anyone who designs a new industrial process without making it as efficient as possible is an idiot, wasting his (or her - chemical engineering is a profession which doesn't require a penis) employer's money. That's generally an incentive to efficiency.

      Putting the basalt (gravel or dust) on trains for the majority of the necessary transport distance, and (electric) trucks from railhead to point-of-use are obvious "low-hanging fruit" for maximising the benefits of such a strategy.

  • What's the cost? (Score:4, Interesting)

    by azcoyote ( 1101073 ) on Thursday July 09, 2020 @05:43AM (#60278372)
    TFA doesn't seem to indicate how much CO2 will be generated by collecting, crushing, and spreading this rock dust. Maybe the original article does the calculations, but I can't access it atm. It seems that the weight of rock would make it require a lot of energy (and a lot of waste CO2 from energy production) just to put such a plan underway. Moreover, is it possible that CO2 will be released from the rock itself when crushed? (I'm no geologist, but I wonder whether the quarrying will expose any kind of rock that would be more likely to dissolve in the open air?)
    • China, India, the USA and Brazil have great potential to help achieve average global CDR goals of 0.5 to 2 gigatonnes of carbon dioxide (CO2) per year with extraction costs of approximately US$80–180 per tonne of CO2.

      A lot of that will be energy cost, as it's mining. "energy cost" is measured in $/barrel of oil, so I smell BS.

      How much is 0.5 to 2 gigatonnes of CO2 compared to current emission levels? Not a lot, maybe around 5%:

      https://www.climate.gov/sites/... [climate.gov]

      "Vast amounts", yes, but compares

    • TFA doesn't mention the costs- but the Science article does go into the calculations quite extensively. If you don't want to sign up for Science- I suspect you can get the article via sci-hub.

  • This is just a scheme concocted by the rock industry to sell their useless dust.
    • Or maybe it's a scheme by Dwayne "The Rock" Johnson trying to dust off his wrestling gear and to return to wrestling after he heard that The Undertaker is quitting.

    • There is no industry more powerful or more vengeful than Big Dust. Watch your back!
    • Actually it's a scheme that was first proposed in the 1850s as a way of replenishing the mineral content of soils which had been heavily farmed. This is just the latest twist on the much studied process of "weathering". I first heard about it before starting the Soil Science part of my geology degree, in the 1980s. It very definitely wasn't new then.

      Old process, new variation, for new reasons.

  • The title really says it all but
    we cannot combat a problem caused by irresponsible use of our planets resources (fossil fuels) with that of another.

    We have about 5yrs left to get to carbon net zero. The carbon in our atmosphere that is causing global heating is from historic emissions. That which we are emitting today ( at an increasing rate ) hasnt even begun to take effect yet.

    We are on track for a 4 degree average Global Temperature rise which will result in catastrophic loss of life. Since 1970 over 60

    • by rho ( 6063 )

      We are on track for a 4 degree average Global Temperature rise which will result in catastrophic loss of life

      Sounds like an effective CO2 mitigation strategy to me.

      • Unfortunately not - as i explained in the original post. The Co2 in the atmosphere thats causing Global heating is historical it takes around 30yrs for todays emissions to contribute to this process. If we do nothing and throw caution to the wind as you suggest, it wont mitigate anything at all. 4 degrees is the point of no return - the point at which the carbon that is sequestered in the soil and under the permafrost gets added into the mix.

  • What's the deal with The Guardian wanting to dump things to "solve" the CO2 problem?

    https://www.theguardian.com/environment/2012/jul/18/iron-sea-carbon

    Lets dump things, in spite of the inherent drawbacks to the plan! In this case it's changing fields PH balance in spite of the crops, in the Iron fertilization it's in spite of the deep sea oxygen levels possibly killing off life there.
  • The OP suggests using finely ground rock (e.g. rock dust). I'd like to ask if this has any impact on the pH balance of the soil after rain?

    Experience tells me that when you reduce a lump of solid matter to a dust, you massively increase the surface area relative to the volume, a condition which accelerates the ability of water to dissolve the substance. (This is why, if you were unable to swallow medicine tablets as a kid, one of your parents would crush a tablet between two tea spoons, stir it in to a g
    • CO2 is absorbed into the rain to create carbonic acid, which reacts with the rock minerals to create carbonates, which are weakly alkaline. So it wouldn't have the instant effect that spreading limestone would, but it would slowly sweeten the soil

    • (This is why, if you were unable to swallow medicine tablets as a kid, one of your parents would crush a tablet between two tea spoons, stir it in to a glass of water and have you drink the water).

      Depending on the medication, your parents (well, the generic parents, not necessarily your parents) could well have killed you.

      Many medications are dispensed in quite closely engineered packages (pills) designed to release their component into the bloodstream (via digestive juices) over a period of hours, not ov

  • The danger of using fear to preach change is that you get ideas like this that just might be adopted if people are scared enough.

    We are humans. We will either change our wasteful ways or adapt to the new normal. We've been doing it for millennia and we will continue to do so.

  • I'd already be happy if they left the rain forests standing, but as long as they keep cutting and burning them down are all these new solutions only painful to watch.

    • Comment removed based on user account deletion
      • Meanwhile, we have people bitching about grocery shopping with plastic bags.

        If you'd seen the trees in Mexico choked to death by being covered with plastic shopping bags, you might bitch about them too.

        • by rldp ( 6381096 )

          why are mexicans such filthy litter bugs?

          they just throw shit on the ground wherever they are, there are no trash cans anywhere

  • Making concrete is supposed to be responsible for 8% of global CO2 emissions. It is made from the same stuff that, when spread of fields, supposedly traps CO2. So, are we dealing with BS, bad math, or a missed opportunity?
  • by Sethra ( 55187 ) on Thursday July 09, 2020 @07:58AM (#60278644)

    Any amount of acidity and those carbonates will release the co2 and leave behind SALT. Salt is something hard to remove from land and is toxic to most crops.

    This is a foolish plan. Leave the basalt dust where it is - it can soak up co2 at the foot of volcanoes.

  • what could possibly go wrong

  • by morgauxo ( 974071 ) on Thursday July 09, 2020 @10:29AM (#60279118)

    Sounds nice but rock is heavy. Heavy things require more energy to move. So I hope someone is taking into account how much CO2 would be produced gathering up all this mining waste and transporting it to fields all around the country and spreading it.

    If it still comes out negative then great!

    • by PPH ( 736903 )

      Spread out on fields is useful for increasing the absorption surface area. But there are other ways to do this. Perhaps nearer the rock dust sources. As someone else pointed out, a byproduct of this will be salt. So keeping the process confined to locations where this salt may easily be dealt with is also a factor.

  • So, basalt is -- quickly cooled magma from ancient volcanic eruptions.

    Volcanic soils are well known for fertility, which is why people have historically insisted on farming the slopes of volcanoes in the face of the risk of getting blown up/incinerated/burned alive/asphyxiated/all of the above.

    This is probably due to the availability of a whole lot of beneficial trace minerals in the soil.

    So, it's fairly probable that this will result in better crop yields in general. Plus, as it's natural rock, and not "c

  • by cnaumann ( 466328 ) on Thursday July 09, 2020 @01:40PM (#60279896)

    Why spread it on fields? Why not use it to capture CO2 at the source? Coal power plant or concrete works?

  • China in particular has some hideous heavy metal pollution in their farmland from industrial activity/burning coal. Can some of these "rock dust" techniques pick up heavy metals in the process of decaying into carbonates?

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