3 ms·

Imagine the lead contamination also

hinkley 1y ago
I saw a How it’s Made-esque show on aluminum recycling just a couple years ago, which is when I learned that aluminum-lead alloys are a thing, and have to be separated. They used a pneumatic blast picker, an x ray machine, and real time image processing to separate the lead from the other alloys. I’ve seen other such systems before, and in those the camera was usually around 30ms up the conveyor from the picker and it pushes the targeted materials into a separate hopper. The scan is parallelized to keep it real time.
- arresin 1y ago
  Recycling is pretty amazing. You have to imagine some lead is getting into the aluminium yeah?
  - fragmede 1y ago
    You have to imagine it's possible. Thankfully, aluminum cans have a plastic liner that separates the liquid from the metal container.
  - hinkley 1y ago
    It’s a bit fuzzy but I think these guys were making window frames rather than food grade materials. I do know that for certain impurities in metal recycling, they have a tendency to accumulate at the top or bottom of the billet, so cutting off those sides to make the billet square removes a lot of sins. But some documentaries don’t show this step, and some the billet doesn’t appear to have been modified before subsequent use. It’s possible that there are steps we aren’t shown/skipped as either trade secrets or too complex to explain.
- 7373737373 1y ago
  In addition to x-rays, hyperspectral cameras can also be used to discern material composition at least superficially: https://www.photonics.com/Articles/Hyperspectral_Imaging_Assesses_the_Sweetness_of/a68686 https://www.photonics.com/Articles/Hyperspectral_Imaging_Ass... https://www.specim.com/hyperspectral-imaging-applications/hyperspectral-imaging-in-recycling-and-waste-management/ https://www.specim.com/hyperspectral-imaging-applications/hy... awesome tech
  - hinkley 1y ago
    Yeah the time before that when I encountered such a picker, someone was trying to recycle mixed plastics by chopping them up and the somehow with cameras they could see which plastic type it was. I’m sure they were using more than visible light to accomplish that. Sadly haven’t heard much since so I don’t know if they are still around, if it didn’t work at all or if they just couldn’t make it cheap enough. I don’t recall the name of the group. One is mentioned in your link and they achieves 98% purity, which may not be sufficient for industrial use.

I saw a How it’s Made-esque show on aluminum recycling just a couple years ago, which is when I learned that aluminum-lead alloys are a thing, and have to be separated. They used a pneumatic blast picker, an x ray machine, and real time image processing to separate the lead from the other alloys. I’ve seen other such systems before, and in those the camera was usually around 30ms up the conveyor from the picker and it pushes the targeted materials into a separate hopper. The scan is parallelized to keep it real time.

arresin 1y ago
Recycling is pretty amazing. You have to imagine some lead is getting into the aluminium yeah?
- fragmede 1y ago
  You have to imagine it's possible. Thankfully, aluminum cans have a plastic liner that separates the liquid from the metal container.
- hinkley 1y ago
  It’s a bit fuzzy but I think these guys were making window frames rather than food grade materials. I do know that for certain impurities in metal recycling, they have a tendency to accumulate at the top or bottom of the billet, so cutting off those sides to make the billet square removes a lot of sins. But some documentaries don’t show this step, and some the billet doesn’t appear to have been modified before subsequent use. It’s possible that there are steps we aren’t shown/skipped as either trade secrets or too complex to explain.
7373737373 1y ago
In addition to x-rays, hyperspectral cameras can also be used to discern material composition at least superficially: https://www.photonics.com/Articles/Hyperspectral_Imaging_Assesses_the_Sweetness_of/a68686 https://www.photonics.com/Articles/Hyperspectral_Imaging_Ass... https://www.specim.com/hyperspectral-imaging-applications/hyperspectral-imaging-in-recycling-and-waste-management/ https://www.specim.com/hyperspectral-imaging-applications/hy... awesome tech
- hinkley 1y ago
  Yeah the time before that when I encountered such a picker, someone was trying to recycle mixed plastics by chopping them up and the somehow with cameras they could see which plastic type it was. I’m sure they were using more than visible light to accomplish that. Sadly haven’t heard much since so I don’t know if they are still around, if it didn’t work at all or if they just couldn’t make it cheap enough. I don’t recall the name of the group. One is mentioned in your link and they achieves 98% purity, which may not be sufficient for industrial use.