What other applications for this could there be?
Sound waves used to separate microplastics from laundry wastewater
11–20 of 47 posts
Re: Sound waves used to separate microplastics from laundry wastewater
#12Or we could stop making clothes out of materials that shed microplastics. And while we're at it, cotton too for the vast amounts of water it uses. Industrial hemp and linen are far more sustainable options. Tencel looks like a great replacement for cotton and uses wood cellulose.
Cotton is softer than hemp and it's lighter than hemp. And unlike either of them, cotton is slightly elastic.
If you've ever had linen sheets you know that they get softer and looser over time.
There are companies that specialise in making clothing out of flax, but a quick look at their designs showcase just how bad linen is for clothing. The only linen garments that resemble the cut / silhouette of their standard counterparts are blouses and dresses.
I'd love to see a comparison of water required to make a square yard of cotton textile vs rayon (tencel is a form of rayon)
Re: Sound waves used to separate microplastics from laundry wastewater
#13Or we could stop making clothes out of materials that shed microplastics. And while we're at it, cotton too for the vast amounts of water it uses. Industrial hemp and linen are far more sustainable options. Tencel looks like a great replacement for cotton and uses wood cellulose.
Or we could stop making plastic.
Or at least the 90% of it making junk.
Even if we separate it, it still exists, as does basically all the plastic we've ever produced. Even separated, at the rate we're producing it, wherever we put it will overflow.
Re: Sound waves used to separate microplastics from laundry wastewater
#14What is it about Soundwaves that allow plastics to move in a direction?
Re: Sound waves used to separate microplastics from laundry wastewater
#15Or we could stop making clothes out of materials that shed microplastics. And while we're at it, cotton too for the vast amounts of water it uses. Industrial hemp and linen are far more sustainable options. Tencel looks like a great replacement for cotton and uses wood cellulose.
Or we could stop making plastic. Or at least the 90% of it making junk. Even if we separate it, it still exists, as does basically all the plastic we've ever produced. Even separated, at the rate we're producing it, wherever we put it will overflow.
wherever we put it will overflow.
The scarcity of landfill space is a myth sparked by the infamous "garbage barge", which nobody accepted because it came from the NY mafia and was getting too much attention, not because there was no room for it.
https://en.wikipedia.org/wiki/Mobro_4000
This Planet Money episode is a good listen: https://www.npr.org/2019/07/09/739893511/episode-925-a-mob-b...
Re: Sound waves used to separate microplastics from laundry wastewater
#16What 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.
I am more familiar with resonance in an electrical domain more so than a mechanical one.
How do they determine at what frequency to actuate the piezos in order to match the resonant frequency of these plastic particles? Is it just 'guestimated' or is there a more systematic way?
Re: Sound waves used to separate microplastics from laundry wastewater
#17Earlier quoted context omitted.
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.
I am more familiar with resonance in an electrical domain more so than a mechanical one. How do they determine at what frequency to actuate the piezos in order to match the resonant frequency of these plastic particles? Is it just 'guestimated' or is there a more systematic way?
My guess would be that they choose the frequency based on the speed of sound in the liquid such that the nodes in the standing wave occur at a designed location in the chamber where the separation occurs.
Re: Sound waves used to separate microplastics from laundry wastewater
#18I'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.
Re: Sound waves used to separate microplastics from laundry wastewater
#19Earlier quoted context omitted.
Amusing but I think aiphex was considering the possible reuse of this tech against the pacific gyre.
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"?
Re: Sound waves used to separate microplastics from laundry wastewater
#20What other applications for this could there be?
Filtering beer?