4 ms·

Maybe I am missing something, but I don’t see how this is feasible at all. Running a mill filled with tons of earth for a day at 450 RPM seems to be an enormou

Maybe I am missing something, but I don’t see how this is feasible at all. Running a mill filled with tons of earth for a day at 450 RPM seems to be an enormous amount of energy expenditure relative to the PFAS you’d be able to destroy at the concentrations in the US. For their context, in which it was firefighting material in a small training zone, it seems like a great fit, but for widespread deployment this seems like a stretch.

toomuchtodo 3y ago
It's a good candidate load for excess renewables that would otherwise be curtailed. Similar to how direct air carbon capture is sited where grid carbon intensity is low (Orca in Iceland, for example). Might need some Megapacks or other battery storage to arbitrage, but that can be built into the cost (capturing various incentives in the process). From a quick glance, everything can be shipped to processing sites in containers. Conveniently, brownfields are also ideal for redevelopment with renewables. Get enough solar and batteries on site to startup, and then continue deploying as you remediate and possibly build transmission to the closest substation.
- IshKebab 3y ago
  There are much better uses for excess renewables load.
  - ryeights 3y ago
    Namely?
    - IshKebab 3y ago
      Aluminium production, hydrogen production, data centres, battery storage, sending it to other countries, etc. You can't object "but then you have to build X" because you have to build stupid ball mills too. They aren't free.
    - pxeger1 3y ago
      Hydrogen production is a common suggestion. Is it better?
      - undersuit 3y ago
        Using the excess energy to produce hydrogen will depress the value of hydrogen until it's no longer profitable to produce hydrogen at those rates and then you have room for ball milling in the economics again.
        remexre 3y ago
        Or until there's not enough excess energy to continue producing hydrogen; I don't see a reason why we'd expect the hydrogen to become unprofitable (water to become too expensive?) first.
        undersuit 3y ago
        Oil price changes disrupt oil operations all the time. The hydrogen energy economy will have times where it's not profitable for an individual actor to generate hydrogen too.
AnthonBerg 3y ago
Throwaway idea: Maybe it can be an energy-storage flywheel at the same time?
- cyann 3y ago
  Flywheel are efficient for high power in short duration: https://en.wikipedia.org/wiki/Flywheel_energy_storage https://en.wikipedia.org/wiki/Flywheel_energy_storage Usually used during a short period of time before the diesel generator can be fully operational.
- cwillu 3y ago
  The nature of ball milling makes it a very inefficient flywheel: The energy of the wheel is going into repeatedly lifting the material. That energy is lost: it's not transferring that energy back into the rotational energy of the wheel every time it falls, but into breaking up the material against the bottom of the wheel, more or less perpendicularly to the direction of the wheel's travel at that point.
- Timothycquinn 3y ago
  Maybe they can put these near power plants and use for power factor correction.
CameronNemo 3y ago
Well considering that the US military has tried to incinerate the firefighting foam they have in stock with poor effects (massive air pollution and soil contamination in nearby areas), it seems to have some utility. But yeah this whole PFAS cleanup project is going to be a long haul.
Chris2048 3y ago
Can they filter the target compound out first?
- silon42 3y ago
  My first question... I'd not want to crush the soil if possible.
suprjami 3y ago
I take findings like this with a grain of salt. They're saying it's possible. Now we need further research to make the process viable at various scale. Nobody sat there with the first combustion engine and said "well this is too much effort, nobody will ever make another one of these" with the same sort of thought process.
- jdlshore 3y ago
  I get your point, but check out the history of the steam engine. The first one was invented in ~30 BC. Additional attempts were made in the 1500s and 1600s. It took until 1712 before it was commercially viable.
  - suprjami 3y ago
    Sure, check the rest of human history though. Things moved at a fairly glacial pace until the industrial revolution. Since computers we've accelerated that even more. Things move very fast these days compared to 2000 years ago.

toomuchtodo 3y ago

It's a good candidate load for excess renewables that would otherwise be curtailed. Similar to how direct air carbon capture is sited where grid carbon intensity is low (Orca in Iceland, for example). Might need some Megapacks or other battery storage to arbitrage, but that can be built into the cost (capturing various incentives in the process). From a quick glance, everything can be shipped to processing sites in containers. Conveniently, brownfields are also ideal for redevelopment with renewables. Get enough solar and batteries on site to startup, and then continue deploying as you remediate and possibly build transmission to the closest substation.

IshKebab 3y ago
There are much better uses for excess renewables load.
- ryeights 3y ago
  Namely?
  - IshKebab 3y ago
    Aluminium production, hydrogen production, data centres, battery storage, sending it to other countries, etc. You can't object "but then you have to build X" because you have to build stupid ball mills too. They aren't free.
  - pxeger1 3y ago
    Hydrogen production is a common suggestion. Is it better?
    - undersuit 3y ago
      Using the excess energy to produce hydrogen will depress the value of hydrogen until it's no longer profitable to produce hydrogen at those rates and then you have room for ball milling in the economics again.
      - remexre 3y ago
        Or until there's not enough excess energy to continue producing hydrogen; I don't see a reason why we'd expect the hydrogen to become unprofitable (water to become too expensive?) first.
        undersuit 3y ago
        Oil price changes disrupt oil operations all the time. The hydrogen energy economy will have times where it's not profitable for an individual actor to generate hydrogen too.

AnthonBerg 3y ago

Throwaway idea: Maybe it can be an energy-storage flywheel at the same time?

cyann 3y ago
Flywheel are efficient for high power in short duration: https://en.wikipedia.org/wiki/Flywheel_energy_storage https://en.wikipedia.org/wiki/Flywheel_energy_storage Usually used during a short period of time before the diesel generator can be fully operational.
cwillu 3y ago
The nature of ball milling makes it a very inefficient flywheel: The energy of the wheel is going into repeatedly lifting the material. That energy is lost: it's not transferring that energy back into the rotational energy of the wheel every time it falls, but into breaking up the material against the bottom of the wheel, more or less perpendicularly to the direction of the wheel's travel at that point.
Timothycquinn 3y ago
Maybe they can put these near power plants and use for power factor correction.

CameronNemo 3y ago

Well considering that the US military has tried to incinerate the firefighting foam they have in stock with poor effects (massive air pollution and soil contamination in nearby areas), it seems to have some utility. But yeah this whole PFAS cleanup project is going to be a long haul.

Chris2048 3y ago

Can they filter the target compound out first?

silon42 3y ago
My first question... I'd not want to crush the soil if possible.

suprjami 3y ago

I take findings like this with a grain of salt. They're saying it's possible. Now we need further research to make the process viable at various scale. Nobody sat there with the first combustion engine and said "well this is too much effort, nobody will ever make another one of these" with the same sort of thought process.

jdlshore 3y ago
I get your point, but check out the history of the steam engine. The first one was invented in ~30 BC. Additional attempts were made in the 1500s and 1600s. It took until 1712 before it was commercially viable.
- suprjami 3y ago
  Sure, check the rest of human history though. Things moved at a fairly glacial pace until the industrial revolution. Since computers we've accelerated that even more. Things move very fast these days compared to 2000 years ago.