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Sound waves used to separate microplastics from laundry wastewater

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Re: Sound waves used to separate microplastics from laundry wastewater

#21
post #19
post #9

Earlier quoted context omitted.

If we cut off the microplastics at the source then the gyre will eventually take care of itself. The problem right now is that we’re continually adding more and more pollution.

What do you mean "take care of itself"?

It'll make its way through the food chain and gradually clear up. Yes, it's going to harm a lot of ocean life in the mean time, but there's not much we can do about that. It's like trying to get red wine out of the white carpet and back into the bottle.

We should stop spilling the wine or at the very least drink it somewhere safer.

Re: Sound waves used to separate microplastics from laundry wastewater

#22
If this works like non-newtonian fluids, I imagine "finding the right shape" or series of tones/patterns works well in bulk.

https://m.youtube.com/watch?v=SYMvOxIsES4

I don't have any hard numbers, but it almost seems like we could easily spend a trillion dollars fixing a problem caused by a 100 billion dollar industries by-products.

What would a carbon credit scheme look like if it were for microplastics?

Re: Sound waves used to separate microplastics from laundry wastewater

#23
post #18

I've never owned a polyester garment that could be washed in water. Aren't they all dry-clean only? Blends (like denim) I can see but in general it seems like people just wash their clothes too often and use the machine too much instead of hand-washing.

No I just checked and many clothes like jackets, swim shorts and blue jeans the first 2 on the list made from 100% polyester are supposed to be machine washed. Save yourself some money and throw that clothing in the wash machine on delicate and you should be fine.

Re: Sound waves used to separate microplastics from laundry wastewater

#24
post #7
post #5

Earlier quoted context omitted.

Generally, there is not marine life in the drain line of a washing machine.

Amusing but I think aiphex was considering the possible reuse of this tech against the pacific gyre.

Where in the FA does it talk about using it in the ocean?

Re: Sound waves used to separate microplastics from laundry wastewater

#26
post #8

I use a Cora Ball [1] in my laundry for the same purpose. Studies say it is only 26% effective, better than nothing. 1: https://coraball.com/

Thanks for sharing that. I use a lot of polyester garments for sports and feel kinda crumby knowing it really hurts the environment.

Hopefully these sound wave systems can be adapted to municipal water systems so as to remove the consumer as the point of failure. Really cool to see the technology that creates Chladni figures being applied to something so useful.

Reminds me of how things start off as entertainment many times, and eventually make a way into an industrial application.

Re: Sound waves used to separate microplastics from laundry wastewater

#27

What is it about Soundwaves that allow plastics to move in a direction?

Resonant waves in a liquid can cause particles of different sizes to move toward the nodes or anti-nodes of a standing wave. A secondary effect is the particles can conglomerate and fall out depending on density.

Note To Future Self:

There's an interesting Physics question posed here, which looks something like this:

If resonant waves, in this case of sound, can cause particles of different sizes to move towards the nodes or anti-nodes of standing waves, then if we consider a completely different area of physics, that is, the case of electroplating metals with electricity, that is, we have an electrode of metal A (for example, Copper), and an electrode of metal B (for example, Gold), in some electrolyte, for example, salt water, then does the electroplating procedure (via electricity) mimic what's happening to the microplastics in water, via sound waves, but just at a smaller wave scale?

In other words, maybe electricity does the same thing as what happens to the sound/microplastics -- but the electricity is a wave which is much faster in frequency, and much smaller?

Now, there's another aspect of all of this too. See, if we can get conglomeration or dissipation of microplastics via the use of sound, then perhaps this mimics the creation or destruction of matter (well, let's say 'particles' at this point, "smaller pieces of matter"), that is, the "clumps" of less rarified/more dense substances inside of more rarified/less dense substances...

Anyway, the principle at work here might be the starting point for Star Trek's food replicator... maybe this is Star Trek's Food Replicator version 0.000000001 (just applied to plastic particles in water, not food/matter particles from air, obviously... )

Note: I don't claim any correctness in the ideas presented above; merely that more experimentation/research might need to be done... see the "Note To Future" self part...

Re: Sound waves used to separate microplastics from laundry wastewater

#28

If this works like non-newtonian fluids, I imagine "finding the right shape" or series of tones/patterns works well in bulk. https://m.youtube.com/watch?v=SYMvOxIsES4 I don't have any hard numbers, but it almost seems like we could easily spend a trillion dollars fixing a problem caused by a 100 billion dollar industries by-products. What would a carbon credit scheme look like if it were for microplastics?

The effect you're thinking of isn't relegated to just non-Newtonian fluids.

https://en.wikipedia.org/wiki/Cymatics

Re: Sound waves used to separate microplastics from laundry wastewater

#29

What other applications for this could there be?

I worked on a project using a similar concept for concentrating micro-algae in the water solution it is grown in. The previous method of extracting micro-algae was filtration or centrifuges. Filters get full too quickly and need regular attention, and centrifuges take too much energy since the density of the particles were very close to the density of water and didn't spin out easily.

We tried using standing acoustic waves to organize and "conclomerate" the micro-algae in the flow and siphon off water quite similarly to the image in the article. It "sort of" worked but only when the flow rate was really, really low because these forces are totally dominated by drag forces and even the smallest levels of turbulence remixes the solution.

What else could this be used for? Think of something that doesn't play nicely with filters or centrifuges and doesn't need to be processed at really high flow rates. Applications in the medical industry come to mind.

Re: Sound waves used to separate microplastics from laundry wastewater

#30

If this works like non-newtonian fluids, I imagine "finding the right shape" or series of tones/patterns works well in bulk. https://m.youtube.com/watch?v=SYMvOxIsES4 I don't have any hard numbers, but it almost seems like we could easily spend a trillion dollars fixing a problem caused by a 100 billion dollar industries by-products. What would a carbon credit scheme look like if it were for microplastics?

The effect you're thinking of isn't relegated to just non-Newtonian fluids. https://en.wikipedia.org/wiki/Cymatics

Cool! I was thinking of granular convection using vibrations, but cymatics and -nf's have much more entertaining videos to visualize sound.

https://m.youtube.com/watch?v=mmPpUztcqB8

> What would a carbon credit scheme look like for microplastics?

A payment plan for a ransom...(insert punchline rimshot here)

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