Also, in bigger cities(Oslo in my case), even if you throw empties in public trash cans, they get fished out by various types of poor people who walk around all day collecting them. Though I tend to leave them next to the trashcan as long as it's not too windy, just as a nice gesture to the less fortunate. Or, often you'll see one of them as you finish your drink and you just hand them the bottle. Of course, I'd prefer a society where people didn't need to do this to get their next fix or meal or whatever it is, but it is sort of neat that utrash sorting can just naturally emerge in a society once the trash is imbued with monetary value.
One wonders why we don't do this with larger categories of garbage that needs to be sorted. I suppose bottles and cans are fairly easy to semi-automate given their fairly standardised shapes. But that just feels like an implementation detail.
In the poorer districts of Ho Chi Minh City, like Q4, Go Vap, etc, it is similar yet different. Each evening, folks set their garbage bags directly on the curb. At night, other people rip open the bags and scatter the trash in the street looking for anything salvageable. Finally, around midnight, city employees walk the streets pushing wheeled bins and sweep up the trash. When it rains, the trash is carried to clog drains, causing large-scale flooding.
Not a great system for many reasons, not least of which is relying on truly poor people. But they are remarkably efficient at extracting value from the waste stream.
Automated recyclable separation is hard and fascinating. Magnets for ferrous metals. Something about non-ferrous metal and eddy currents for aluminum. Infrared cameras and mechanical arms to detect and separate types of plastics. Blower systems to extract paper. Tumblers with various sized holes (like those coin counting machines) for other separation. (Source: Not that great. I just watched a few Youtubes.)
Here in Vancouver we have little shelves around garbage cans for the empties to go, and someone will come by in a few minutes to collect it for the deposit.
One wonders why we don't do this with larger categories of garbage that needs to be sorted. I suppose bottles and cans are fairly easy to semi-automate given their fairly standardised shapes. But that just feels like an implementation detail.