It’s because you can’t recycle plastic really. Each time you heat it up to melt it it loses its properties. A recyclable material is for instance aluminium, which keeps on being awesome. I tried various recycled plastics for a business I run, none of it was strong enough. Recycled lego, recycled car bumpers, nada. And then the question is - why would I buy the recycled plastic that doesn’t work when it’s like 30 cents cheaper. Pellets are so cheap in fact, that I could buy a tonne, use up 100kgs, throw the rest away and still be fine.
Once they touch the factory floor’s floor, plastics become filthy and cannot be used for high-quality applications - food wrappers, anything with body contact. Oils and heavy metals are the biggest contaminants, a plastics-producing company I used to work for concluded. They either sent it all to a recycling factory or used it for very low-quality stuff like trash bags.
Now with post-consumer plastics, not only are they extremely heterogeneous, they will also have even worse contaminants like mold which proved to be very resistant to cleaning, a EU study concluded. So you might want to pyrolyze them like you do with crude oil, but there’s just too much O, N, S and halogens, so the output will be too corrosive, but also too heterogeneous for it to make economic sense.
Maybe there is something, but tbh why bother when virgin pellets are better. The best plastic recycling strategy is to not make it in the first place. Or just use other types of packaging - alu cans, glass bottles, paper containers, whatever.
Also additives soak water like crazy. Moisture is a huge problem when making parts - you need to dry some types of plastic pellets in industrial dryers, which eats up a ton of electricity - since they are often running off of compressed air out of a compressor. Most plastic comes in natural colors to which you add additives to change to the color you want. Simply doing that (2% by weight) is a difference between not having to dry at all (since some plastics just don’t absorb water - i.e. polyolefins - which high density variant is what bottles for shower gel, shampoos are made of) and having to dry it for like 6 hours before use.
It’s because you can’t recycle plastic really. Each time you heat it up to melt it it loses its properties. A recyclable material is for instance aluminium, which keeps on being awesome. I tried various recycled plastics for a business I run, none of it was strong enough. Recycled lego, recycled car bumpers, nada. And then the question is - why would I buy the recycled plastic that doesn’t work when it’s like 30 cents cheaper. Pellets are so cheap in fact, that I could buy a tonne, use up 100kgs, throw the rest away and still be fine.
Once they touch the factory floor’s floor, plastics become filthy and cannot be used for high-quality applications - food wrappers, anything with body contact. Oils and heavy metals are the biggest contaminants, a plastics-producing company I used to work for concluded. They either sent it all to a recycling factory or used it for very low-quality stuff like trash bags.
Now with post-consumer plastics, not only are they extremely heterogeneous, they will also have even worse contaminants like mold which proved to be very resistant to cleaning, a EU study concluded. So you might want to pyrolyze them like you do with crude oil, but there’s just too much O, N, S and halogens, so the output will be too corrosive, but also too heterogeneous for it to make economic sense.
What was it like working in plastics production? I imagine you were breathing in vapors all the time?
Maybe with some additives? Or removing them, in the first place? But expensive i guess.
Maybe there is something, but tbh why bother when virgin pellets are better. The best plastic recycling strategy is to not make it in the first place. Or just use other types of packaging - alu cans, glass bottles, paper containers, whatever.
Also additives soak water like crazy. Moisture is a huge problem when making parts - you need to dry some types of plastic pellets in industrial dryers, which eats up a ton of electricity - since they are often running off of compressed air out of a compressor. Most plastic comes in natural colors to which you add additives to change to the color you want. Simply doing that (2% by weight) is a difference between not having to dry at all (since some plastics just don’t absorb water - i.e. polyolefins - which high density variant is what bottles for shower gel, shampoos are made of) and having to dry it for like 6 hours before use.