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Comment by rm_-rf_slash | Hacker News Reader

I wonder how useful this technology could be to zero-sort recycling. As much of a hippie as I am, I don't think recycling can be solved by green bins and awareness campaigns, but instead by the simplicity of throwing everything into one bin that gets sorted when it reaches the processing plant.

It would also be helpful if this could sort organic material for use in compost and sell it. Maybe even brand it. How much do you think people would pay to use compost from Beverly Hills celebrities in their garden?

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There's similar tech already in use. Sorting flakes of different plastics can be done by "vision" if you have different wavelengths of light, then tiny air blasts can direct them into the right hopper.

Though, the more raw sorting that can be done the better for the system. Where I am, we put food waste in its own bin, and frankly it just seems natural after a very short time.

Also for berries, waves of berries are visually identified and blasts the "bad ones" out of the stream. Very impressive (and fast) to watch.

I can't find the video, but apparently at some canneries there used to be a person who would very rapidly hit the tops of cans with a metal rod and listen to the noise that it made. "Bad" cans sounded different and would be removed from the line. After years of practice these workers were inhumanly fast at the job.

And dead inside.

If you haven't seen a high speed visual sorter, it's impressive.[1] It's economically feasible, and routine, to inspect each individual berry with cameras, lasers, and computers. Size, shape, and color are all checked. Some plants even look at every grain of rice. The items are sorted with air jets.

[1] https://www.youtube.com/watch?v=EPwMDMruYyk

Not berries, but here's the same sort of machine: https://youtu.be/7nTtjVFuY6M?t=47

Some false positives, but it's incredible how fast those can run.

It's used for a lot of food products like chips too.

I suspect it could be useful for some types of recycling, but there are already a lot of tricks employed to separate dissimilar materials - metals and paper products sink, plastics float, field effect and or magnets can move metals, etc. Using CV to recognize materials would be overkill by comparison. But I find watching the bot sort soothing...

I believe WEEE (Waste Electrical and Electronic Equipment) recycling plants use computer vision directly. Recycling plans having multiple optical units with compressed air to then redirect the route of identified items, but I don't know whether this is image recognition or Raman / IR to identify the material. Certainly to differentiate plastics, it will be Raman / IR.

An info vid on a recycling plant, showing the sort of scale and speed of sorting:-

https://youtu.be/SIVKmwzWSuc?t=1m14s

I think the organic material idea is good, but not at a distant collection point. If you throw organic material away --> transport to site --> sort it --> delay --> transport to stores --> transport back to garden I think you lose the energy battle.

If you created local dump sites where trash could be sorted and composted, it could work. You also cut down on the amount (and as a result the energy) of trash that gets thrown in the dump. Obvious obstacles are the inability to get people to use the local sites, the initial costs / availability of land, and the resistance to dumps in neighborhoods.

A potential 2nd level effect would be the long term state of trash dumps. At least some dumps are eventually reclaimed. Would reducing or eliminating the organic content prevent that from happening?

It takes a lot of cultural engineering to get people to be that diligent. I'm from an ultra liberal college town and I'll never forget going away to college and spending 15 minutes looking for the compost bin in my freshman dorm. No dice.

Then you have places like Florida, where nobody recycles. Trash is trash. Throw it away and take it to the curb. Even the most elegant and energy-efficient local dump system would go nowhere with a culture that would rather throw away and forget about it, and this is coming from a state that is most vulnerable to climate change yet is full of beach house-owning republicans who think climate change is a hoax.

Very soon here they're not going to accept garbage with compostable material in it. It'll be interesting how big of a push back that gets, but there is definitely ways to make people feel a bit of pain for living a throwaway culture.

As a Floridian, I'm curious how it works elsewhere. In what ways are systems in other places better? I live in Seminole County and we have recycling bins. It sounds like you think it should go further.

It varies by far more then on a state to state basis. I also grew up in Florida, and we had 2 bins of recycling, one for plastic/metal, one for paper. Moved to NC, we had just 1 can for all recycling, and then they decided that the recycling wasn't worth it, and stopped picking it up. Now everything goes in the trash, which is rather sad.

All your organic material would be contaminated by toxic material by the time it gets to the plant. People throw out all sorts of things...leaking batteries, car oils and fluids, electronics, and even salts wouldn't be great when talking about using it as compost.

Check out ZenRobotics

https://www.youtube.com/watch?v=dUQvdI4QZT0

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