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Comment by cocoggu | Hacker News Reader

I think there is now a real will from the chinese government to limit plastic pollution.

For example, waste sorting started in Shanghai a year ago and started in Beijing last June [0].

This is not the usual waste sorting we are experiencing in Europe, for example, since you need to decline your identity and not make any mistake while sorting or you may get charged.

Probably a bit too invasive (this is China after all) but more thorough for what I consider a good cause.

Besides, the first bans on plastic use will take effect on January [1]. This is only for small items now, but this is a first step, and it also includes production of these items, which is especially impressive considering China supremacy on the production lines.

[0] https://www.scmp.com/news/china/society/article/3016801/shan...

[1] https://www.scmp.com/business/china-business/article/3101241...

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You mentioned Shanghai and Beijing, but note that sorting waste isn't new to the country. I was part of a team that installed a single-stream waste sorting system in China in 2007, prior to the Olympics. It was a very impressive system where all garbage would enter at one end and a large array of machines and people would sort the garbage into recyclables, compost, and the rest for an incinerator. It used all the latest tech, mainly from North America.

I think current garbage sorting is waaay too inefficient, and this is fundamentally limits the recyclability rates.

This is especially obvious when you talk about stuff made of a lot of different materials.

Picking such things apart for different material streams is impossible to scale.

I was thinking, what if governments were mandating mandatory chemical tagging of all common materials, so you can just shred everything, and then separate materials using machines which can distinguish chemical tags.

I think it might be easier to just have machines learn to recognize the top 99.9% of all things thrown away and leave the rest to a a small group (or landfill).

This seems like the obvious solution. I bet a database of 100,000 products would cover the vast majority of all waste worldwide. If you can make a machine to sort those things into 100,000 (virtual) piles, you can then have a specific way to handle each type of thing.

Each manufacturer of those goods can decide how to handle their "pile", and if they design for recyclability, it's going to be easier and cheaper for them. If they can just say "combine our product with these other products made from the same material" that'll work out cheapest. If their answer is "our product contains a mix of various toxic stuff" then they're going to have to pay for some specialist to handle it... In every location this 'pile' exists in every city...

The only place this system doesn't work is for products that change state significantly during consumer use - for example a candle gets mostly burnt away, but the remaining blobs of wax are probably untracable to the original manufacturer.

The problem, as I stated above, is that you will be landfilling significantly more than 0.01%.

There are tons of unrecyclable stuff in regular household garbage. For example, a packaging made of two incompatible in recycling methods plastics are a waste.

I'm describing an approach to sorting. Your response isn't about sorting.

What about waste vaporization? There are far fewer things that are sensitive to being vaporized (meaning far less sorting needed) and the outputs are far cleaner.

Who will pay for electricity?

There are ways to generate massive amounts of power with relatively few inputs

Which ones?

Do you have any good links to the machinery / tech that does that kind of sorting? I've search for it in the past and it seems like I was mostly getting hits on European manufacturers.

The systems use lots of clever tricks, like floating paper and plastics away from metals with water or jets of air, or using eddy currents to push metals out of mixed waste. Here's one example: https://www.popsci.com/technology/article/2013-07/how-it-wor...

Recycling, even plastic bans, are not the most direct or simple fix. The first and key step is to stop dumping it in the river. Getting the plastic into landfills is the first step. Reduction and recycling are the stretch goals.

the first step is DON'T MAKE IT

or make it of something biodegradable

Also:

https://en.wikipedia.org/wiki/China%27s_waste_import_ban

A not insignificant part of the plastic thrown in rivers in South East Asia is consumed in Europe and the USA

> A not insignificant part of the plastic thrown in rivers in South East Asia is consumed in Europe and the USA

I've heard this repeated many times, but every time I go searching for details I always come back with the same results: This is not true.

The garbage in rivers is local.

No one is shipping waste from Europe or USA, but some countries do buy recycling. But of course since they paid for the recycling, they have no interest in then dumping it.

If you have some source showing different I'd be interested in seeing it.

the stat is about oceans and that it comes from those 7-10 rivers

Scientists say otherwise: https://www.europeanscientist.com/en/environment/plastic-for...

If you read the study they don't have great data, so they do a lot of estimating. According to the study itself it's 1% to 7% of recycling that ends up in the ocean.

Obviously any amount is bad, but this isn't a significant source of river plastic.

And to really drive the point home: According to the article the plastic ends up in rivers because of bad local trash management!! (As opposed to deliberate dumping.)

So the solution is exactly as others have said: These countries need modern municipal trash pickup. The problem does not originate in Europe or USA.

BTW: This is a very poor study, for example they use numbers for San Fransisco Bay watershed to estimate numbers for India.

I suspect most the plastic waste I generate is in packaging. I wish shipping companies would use cardboard instead.

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