9 ms·

Down on the farm that harvests metal from plants

131 points by andrewl 7y ago

Anointmous 7y ago
The articles everyone really wants: There's Gold in Them Thar Plants | Phytomining | Live Science https://www.livescience.com/28676-plants-grow-gold.html https://www.livescience.com/28676-plants-grow-gold.html Phytomining? - Gold Refining Forum.com (more articles listed) http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?t=8570 http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?...
Anointmous 7y ago
"The father of modern mineral smelting, Georgius Agricola, saw this potential 500 years ago. He smelted plants in his free time. If you knew what to look for in a leaf, he wrote in the 16th century, you could deduce which metals lay in the ground below."
Gravityloss 7y ago
The Talvivaara mine in Finland uses a novel bio based method to get nickel out of the ore but it has not been super successful so far. But it is in operation, after quite major problems. AFAIU the concentration is so low that traditional methods would not have been profitable.
dehrmann 7y ago
> After a short purification, farmers could hold in their hands roughly 500 pounds of nickel citrate How many rounds of this can you do before you've stripped so much nickel from the ground these trees won't grow?
- andrewl 7y ago
  I wondered that myself. They'd need a succession plan. But high concentrations of certain metals are toxic to many other plants. So maybe the nickel harvesting plants are a first step to preparing the soil for another crop. Only this step allows the farmers to at least partially recover some of their investment in the cleaning step.
  - pfdietz 7y ago
    Another possibility would be to grind up olivine and spread that on the field. Olivine is a nesosilicate (orthosilicate) so it dissolves readily in weak acid conditions. And it's typically a few tenths of a percent nickel. The dissolution of olivine would liberate magnesium ions, which could react with water and CO2, permanently sequestering the CO2 as carbonate.
  - manicdee 7y ago
    The succession plan is reverting to stocks that can handle the elevated levels of nickel still remaining after the commercial viability of bioremediation has been exhausted.
- jessaustin 7y ago
  In the areas where they evolved, they've presumably been present for a very long time. Human action could possibly increase their nickel-concentrating abilities by some small multiplier, but that won't turn human timescales into geologic timescales.
  - Talanes 7y ago
    Those trees would overwhelmingly be falling and decomposing in the same soil they grew in though, so the movement of minerals out of the soil would be minimized.
- JohnJamesRambo 7y ago
  Nickel is not really needed in any large amount for the growth of plants, I assume even these plants don't need it in more than a trace amount to grow. The hydroponic fertilizer I use doesn't even list it on the label and I assume that the only way my plants get it is from impurities in the other minerals. https://www.jacksnutrients.com/online-store/5-12-26-Part-A-p101272607 https://www.jacksnutrients.com/online-store/5-12-26-Part-A-p...
- pvaldes 7y ago
  > 500 pounds of nickel citrate That would be 115 pounds of nickel (plus some water and C02)
- LatteLazy 7y ago
  Isn't the idea that you remove the nickel and then go back to farming "normal" crops? So this is a one off way to mine without destroying the environment. And maybe a way to remove excess metals from soil too. Not a continuous supply. Edit, I guess you could use this technique in waste cleanup too, so maybe once a mine stops producing you plant these trees on the site for one last load. Or you bring waste from the mine (high nickle etc) to farms like this and "replenish" the sites
Pfhreak 7y ago
I wonder if there's a positive gain in drawing metals out with the plants, removing the metal content, and producing biochar with the waste. Then you'd be able to use the plants to remove CO2 from the air and metals from the ground simultaneously. Obviously, there's a finite amount of metal one could draw from any given location, and depending how deep root systems grow there's maybe not a lot of long term value in mining the surface this way. (Though with breeding/engineering programs, perhaps you could get deeper root systems.) It's the sort of stuff that's fun to imagine in a science fiction context and probably doesn't make much practical sense in the real world. Though, maybe getting metals out of the soil is useful in other ways (e.g. cleaning up mine tailings?)
- odyssey7 7y ago
  > Obviously, there's a finite amount of metal one could draw from any given location, and depending how deep root systems grow there's maybe not a lot of long term value in mining the surface this way. My concern was, if this goes into wide use, then we'll be using these specialized species to extract the non-renewable resources that they depend on from their habitats, leading to the species' demise. Edit: Considering "hundreds of mines shovel topsoil into smelters," maybe this is already at risk to begin with.
  - bottled_poe 7y ago
    Sounds a lot like modern agriculture. What’s the difference?
    - odyssey7 7y ago
      Interesting. I guess both can make a location uninhabitable for native species. This one is ironic because the plant being both cultivated and harmed by the agriculture could be the native species itself. Another difference is that with most farming there's an incentive to add things back to the soil and rotate crops, since you want the soil to keep working for you. In this case, there's no incentive to add nickel back to the soil, since extracting that element is the goal. And nature's ability to replenish the nickel is limited.
hinkley 7y ago
> Where nickel is mined and refined, it destroys land and leaves waste. Sounds like this process might have more immediate use as a preventative measure to reduce the footprint of conventional mining processes. Catch the residuals in the tailings and the slag.
neonate 7y ago
https://archive.md/P2sSl https://archive.md/P2sSl
zkms 7y ago
i am not a biologist but i saw an article (https://www.nature.com/articles/s41598-019-38740-2 https://www.nature.com/articles/s41598-019-38740-2) about a related subject a few months ago; namely, that certain species of algae preferentially uptake uranium-235 (the fun fissile isotope) over uranium-238 (the more prevalent isotope), and the numbers they quoted imply an isotopic separation factor that is,,,significant.
- Gravityloss 7y ago
  That's very unexpected. I wonder how do the microbes do it? According to the article, the higher concentration of U235 happens within the cell.
- jimkri 7y ago
  I did not know this, so thanks for sharing! Micro-algae and Macro-algae are great for absorbing metals that are in water, its used in wastewater treatment: https://www.sciencedirect.com/science/article/pii/S1319562X12000332 https://www.sciencedirect.com/science/article/pii/S1319562X1... When you take an algae supplement it also helps to remove metals from the body as well. Algae is great
ptah 7y ago
it sounds like this only works for nickel?

131 points by andrewl 7y ago

The articles everyone really wants: There's Gold in Them Thar Plants | Phytomining | Live Science https://www.livescience.com/28676-plants-grow-gold.html https://www.livescience.com/28676-plants-grow-gold.html Phytomining? - Gold Refining Forum.com (more articles listed) http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?t=8570 http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?...

Anointmous 7y ago

"The father of modern mineral smelting, Georgius Agricola, saw this potential 500 years ago. He smelted plants in his free time. If you knew what to look for in a leaf, he wrote in the 16th century, you could deduce which metals lay in the ground below."

Gravityloss 7y ago

The Talvivaara mine in Finland uses a novel bio based method to get nickel out of the ore but it has not been super successful so far. But it is in operation, after quite major problems. AFAIU the concentration is so low that traditional methods would not have been profitable.

dehrmann 7y ago

> After a short purification, farmers could hold in their hands roughly 500 pounds of nickel citrate How many rounds of this can you do before you've stripped so much nickel from the ground these trees won't grow?

andrewl 7y ago
I wondered that myself. They'd need a succession plan. But high concentrations of certain metals are toxic to many other plants. So maybe the nickel harvesting plants are a first step to preparing the soil for another crop. Only this step allows the farmers to at least partially recover some of their investment in the cleaning step.
- pfdietz 7y ago
  Another possibility would be to grind up olivine and spread that on the field. Olivine is a nesosilicate (orthosilicate) so it dissolves readily in weak acid conditions. And it's typically a few tenths of a percent nickel. The dissolution of olivine would liberate magnesium ions, which could react with water and CO2, permanently sequestering the CO2 as carbonate.
- manicdee 7y ago
  The succession plan is reverting to stocks that can handle the elevated levels of nickel still remaining after the commercial viability of bioremediation has been exhausted.
jessaustin 7y ago
In the areas where they evolved, they've presumably been present for a very long time. Human action could possibly increase their nickel-concentrating abilities by some small multiplier, but that won't turn human timescales into geologic timescales.
- Talanes 7y ago
  Those trees would overwhelmingly be falling and decomposing in the same soil they grew in though, so the movement of minerals out of the soil would be minimized.
JohnJamesRambo 7y ago
Nickel is not really needed in any large amount for the growth of plants, I assume even these plants don't need it in more than a trace amount to grow. The hydroponic fertilizer I use doesn't even list it on the label and I assume that the only way my plants get it is from impurities in the other minerals. https://www.jacksnutrients.com/online-store/5-12-26-Part-A-p101272607 https://www.jacksnutrients.com/online-store/5-12-26-Part-A-p...
pvaldes 7y ago
> 500 pounds of nickel citrate That would be 115 pounds of nickel (plus some water and C02)
LatteLazy 7y ago
Isn't the idea that you remove the nickel and then go back to farming "normal" crops? So this is a one off way to mine without destroying the environment. And maybe a way to remove excess metals from soil too. Not a continuous supply. Edit, I guess you could use this technique in waste cleanup too, so maybe once a mine stops producing you plant these trees on the site for one last load. Or you bring waste from the mine (high nickle etc) to farms like this and "replenish" the sites

Pfhreak 7y ago

I wonder if there's a positive gain in drawing metals out with the plants, removing the metal content, and producing biochar with the waste. Then you'd be able to use the plants to remove CO2 from the air and metals from the ground simultaneously. Obviously, there's a finite amount of metal one could draw from any given location, and depending how deep root systems grow there's maybe not a lot of long term value in mining the surface this way. (Though with breeding/engineering programs, perhaps you could get deeper root systems.) It's the sort of stuff that's fun to imagine in a science fiction context and probably doesn't make much practical sense in the real world. Though, maybe getting metals out of the soil is useful in other ways (e.g. cleaning up mine tailings?)

odyssey7 7y ago
> Obviously, there's a finite amount of metal one could draw from any given location, and depending how deep root systems grow there's maybe not a lot of long term value in mining the surface this way. My concern was, if this goes into wide use, then we'll be using these specialized species to extract the non-renewable resources that they depend on from their habitats, leading to the species' demise. Edit: Considering "hundreds of mines shovel topsoil into smelters," maybe this is already at risk to begin with.
- bottled_poe 7y ago
  Sounds a lot like modern agriculture. What’s the difference?
  - odyssey7 7y ago
    Interesting. I guess both can make a location uninhabitable for native species. This one is ironic because the plant being both cultivated and harmed by the agriculture could be the native species itself. Another difference is that with most farming there's an incentive to add things back to the soil and rotate crops, since you want the soil to keep working for you. In this case, there's no incentive to add nickel back to the soil, since extracting that element is the goal. And nature's ability to replenish the nickel is limited.

hinkley 7y ago

> Where nickel is mined and refined, it destroys land and leaves waste. Sounds like this process might have more immediate use as a preventative measure to reduce the footprint of conventional mining processes. Catch the residuals in the tailings and the slag.

neonate 7y ago

https://archive.md/P2sSl https://archive.md/P2sSl

zkms 7y ago

i am not a biologist but i saw an article (https://www.nature.com/articles/s41598-019-38740-2 https://www.nature.com/articles/s41598-019-38740-2) about a related subject a few months ago; namely, that certain species of algae preferentially uptake uranium-235 (the fun fissile isotope) over uranium-238 (the more prevalent isotope), and the numbers they quoted imply an isotopic separation factor that is,,,significant.

Gravityloss 7y ago
That's very unexpected. I wonder how do the microbes do it? According to the article, the higher concentration of U235 happens within the cell.
jimkri 7y ago
I did not know this, so thanks for sharing! Micro-algae and Macro-algae are great for absorbing metals that are in water, its used in wastewater treatment: https://www.sciencedirect.com/science/article/pii/S1319562X12000332 https://www.sciencedirect.com/science/article/pii/S1319562X1... When you take an algae supplement it also helps to remove metals from the body as well. Algae is great

ptah 7y ago

it sounds like this only works for nickel?