5 ms·

Is there no value in merely separating and gathering this material, even if it's all dumped in a "plastics only" landfill, as opposed to one containing other ty

by cfr2023 3y ago

Is there no value in merely separating and gathering this material, even if it's all dumped in a "plastics only" landfill, as opposed to one containing other types of trash? Isn't keeping different types of waste sorted inherently useful in other ways?

Arn_Thor 3y ago
I suspect you’re right. From my hometown’s local waste authority: After [we have] collected the waste from your bin, the purple dotted bag [with plastic waste] is sent on for collection and pressing before being transported to large sorting facilities in Northern Germany and other places in Europe. Here, 75% of the content in the purple dotted bag (figures from 2019) is recycled, and the remaining waste (often residual waste and food waste that has been incorrectly sorted) is utilized for energy. And more detail: This is how household plastic is recycled: Collected plastic packaging is first finely sorted in Germany, before moving on to recyclers in the same country or elsewhere in Europe. We differentiate between the recycling of household plastic, which is the plastic you sort at home, and plastic packaging from businesses. - The plastic packaging you sort at home is collected by the municipality or an inter-municipal waste company. They press the plastic together into large bales. - Plastretur transports the plastic to a sorting facility. - At the sorting facility, incorrect sorting and contaminants are removed. This can include paper and metal, or other items that ended up in the wrong collection at your home. - Additionally, the plastic is sorted into different qualities, and non-recyclable packaging is removed. The sorting facilities classify the plastic into several plastic qualities such as PP, LDPE, HDPE, PET before it is transported to a recycling plant. - At the recycling plant, the plastic is washed. This process also removes labels and glue. - Then it is ground and melted into small beads, called pellets. Pellets are a raw material that can be used to make new products from recycled plastic.
- bombcar 3y ago
  > remaining waste is used for energy This really is the key - if people weren't so scared of incinerators, the "landfill" problem would be basically solved.
  - infecto 3y ago
    I still don’t fully understand. Would there be unwanted gasses coming out? Could we not burn the specific plastics where it’s economically worth it for electric generation? I don’t know the full science so my assumptions might be wrong but I wonder how much worse it is compared to coal and natty gas plants?
anticorporate 3y ago
Probably, but, separating is actually a really hard problem. People do not do as good of a job separating their own recycling as they think they do. Others don't care at all. MRFs are expensive due to maintenance, labor, and other operating costs, and if there's no cost recovered from the recycling there's little to fund their existence.
- LMSolar 3y ago
  I've toured our local MRF and was shocked at how good it was at robotic / magnetic separation. Incredibly fast AI trained 'pickers' pulling material off a belt (sorting by visually distinct plastic types, e.g. PET vs opaque plastics, paper, etc), combined with some human labor and magnetic extractors. Very high capture rates for all plastics except films - those remain hard to sort / grab. I was not expecting this level of performance...
- cfr2023 3y ago
  Valuable considerations. Seems like a perfect machine learning/robotics application, but probably not one that will receive funding if it's pitched with the objective of, "look now all of this problematic crap is in one place."
  - amluto 3y ago
    I don’t think separating the disgusting mess in mixed recycling is an ML/robotics problem. Neither robots nor human hands can turn food-splattered paper into clean recyclable paper. Nor can they turn plastic/paper composite materials into anything else. Or dirty plastic bags or dirty polystyrene foam or (yuck!) fluorinated HDPE.
    - cfr2023 3y ago
      Fair observations but, doesn't this assume that disposal and containment are truly our only options now and forever? Even so, you think there would be no worthy efficiency gains for pure sorting or materials mining in using machines that can identify known objects effectively, and hands that will go where humans will not?

Arn_Thor 3y ago

I suspect you’re right. From my hometown’s local waste authority: After [we have] collected the waste from your bin, the purple dotted bag [with plastic waste] is sent on for collection and pressing before being transported to large sorting facilities in Northern Germany and other places in Europe. Here, 75% of the content in the purple dotted bag (figures from 2019) is recycled, and the remaining waste (often residual waste and food waste that has been incorrectly sorted) is utilized for energy. And more detail: This is how household plastic is recycled: Collected plastic packaging is first finely sorted in Germany, before moving on to recyclers in the same country or elsewhere in Europe. We differentiate between the recycling of household plastic, which is the plastic you sort at home, and plastic packaging from businesses. - The plastic packaging you sort at home is collected by the municipality or an inter-municipal waste company. They press the plastic together into large bales. - Plastretur transports the plastic to a sorting facility. - At the sorting facility, incorrect sorting and contaminants are removed. This can include paper and metal, or other items that ended up in the wrong collection at your home. - Additionally, the plastic is sorted into different qualities, and non-recyclable packaging is removed. The sorting facilities classify the plastic into several plastic qualities such as PP, LDPE, HDPE, PET before it is transported to a recycling plant. - At the recycling plant, the plastic is washed. This process also removes labels and glue. - Then it is ground and melted into small beads, called pellets. Pellets are a raw material that can be used to make new products from recycled plastic.

bombcar 3y ago
> remaining waste is used for energy This really is the key - if people weren't so scared of incinerators, the "landfill" problem would be basically solved.
- infecto 3y ago
  I still don’t fully understand. Would there be unwanted gasses coming out? Could we not burn the specific plastics where it’s economically worth it for electric generation? I don’t know the full science so my assumptions might be wrong but I wonder how much worse it is compared to coal and natty gas plants?

anticorporate 3y ago

Probably, but, separating is actually a really hard problem. People do not do as good of a job separating their own recycling as they think they do. Others don't care at all. MRFs are expensive due to maintenance, labor, and other operating costs, and if there's no cost recovered from the recycling there's little to fund their existence.

LMSolar 3y ago
I've toured our local MRF and was shocked at how good it was at robotic / magnetic separation. Incredibly fast AI trained 'pickers' pulling material off a belt (sorting by visually distinct plastic types, e.g. PET vs opaque plastics, paper, etc), combined with some human labor and magnetic extractors. Very high capture rates for all plastics except films - those remain hard to sort / grab. I was not expecting this level of performance...
cfr2023 3y ago
Valuable considerations. Seems like a perfect machine learning/robotics application, but probably not one that will receive funding if it's pitched with the objective of, "look now all of this problematic crap is in one place."
- amluto 3y ago
  I don’t think separating the disgusting mess in mixed recycling is an ML/robotics problem. Neither robots nor human hands can turn food-splattered paper into clean recyclable paper. Nor can they turn plastic/paper composite materials into anything else. Or dirty plastic bags or dirty polystyrene foam or (yuck!) fluorinated HDPE.
  - cfr2023 3y ago
    Fair observations but, doesn't this assume that disposal and containment are truly our only options now and forever? Even so, you think there would be no worthy efficiency gains for pure sorting or materials mining in using machines that can identify known objects effectively, and hands that will go where humans will not?