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China builds ‘world’s biggest air purifier’ and it seems to be working

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Re: China builds ‘world’s biggest air purifier’ and it seems to be working

#51

Post by moron4hire »

captainmuon wrote: post #33
gressquel wrote: post #16

Please refrain from using AMP links. We need to take a stance against Googles abuse of monopoly.

Devil's advocate: Google is generous by caching AMP sites on their own servers. The only thing you can't do is to include your own invasive third party tracking (ok, you can use Google's of course), which is bad anyway. But you can still include your ad just as a in the page, no JS and tracking. Like a dumb print ad. I don't really have a problem with that.

There is no such thing as a generous corporation. It goes completely against maximizing shareholder value. Google gets something out of AMP, something they can quantify monetarily.

Re: China builds ‘world’s biggest air purifier’ and it seems to be working

#52

Post by ChuckMcM »

Seems like a reasonable way to pump air through a filter. It will be interesting to see long term effects and maintenance costs (eventually the filters need to be replaced as efficiency would go down with increased air resistance in the tower).

This FastCompany article from 2013 (https://www.fastcompany.com/2682151/5-imaginative-buildings-...) had some additional concepts that could be added.

Re: China builds ‘world’s biggest air purifier’ and it seems to be working

#53

Post by justicezyx »

seanmcdirmid wrote: post #34
eksemplar wrote: post #32

Earlier quoted context omitted.

The bureaucracy typically help business when it works. It’s not meant to be directed by day-to-day driven politicians or exposed to lobbyism. It’s supposed to be a safety net to make sure society keeps on track as it speeds along. That’s what it is in China, with the added benefit of it actually supporting their local and hindering foreign businesses. In a lot of areas it’s us in the west who are stuck behind a hopel…

Our local lakes are still pretty clean, Trump hasn’t dismantled the EPA (yet). Western bureaucracy differs from Chinese bureaucracy in that it is more deterministic, the rules are more obvious and more fairly enforced. In China, there is a huge difference based on your guanxi level. I wouldn’t trade our system for theirs.

According to Trump, Hillary escaped jail time because "Guanxi", or whatever equivalent things to guanxi.

Re: China builds ‘world’s biggest air purifier’ and it seems to be working

#54

Post by staplers »

OskarS wrote: post #50
jhugg wrote: post #48

Earlier quoted context omitted.

That's really interesting. Maybe the pm2.5 is less visible than the PM10, but maybe I'm just way way off. As for the volume of air, I'm most curious where the 15% measurement was taken and how consistent it was. How far from the tower? How many different places were measured? How many days are in the sample? What's the P-Value? But still, thanks. Makes this interesting to think about.

I think PM10 rates are in similar orders of magnitude, in the "micrograms per cubic meter" range, so i don't think it would be that different. Maybe an order of magnitude larger, but not much more. I agree, this is very surprising. Before I saw LeifCarrotson's calculation, I would have thought "tons" was the right unit as well. There's so much polluted air, you'd think that it would add up to some significant amount…

Puts into perspective how much PM burning coal puts into the atmosphere..

EDIT: In 2016, the United States burned roughly 728 million tons of coal, enough to fill a typical railroad car every 4 seconds

Re: China builds ‘world’s biggest air purifier’ and it seems to be working

#55

Post by xkcd-sucks »

Such a mainland solution... The air's dirty, install an air filter. There's lots of air and it's really dirty? Build a bigger air filter!

...especially if my uncle manufactures air filter membranes and needs to get rid of some extra inventory

Re: China builds ‘world’s biggest air purifier’ and it seems to be working

#56

Post by kragen »

LeifCarrotson wrote: post #37
jhugg wrote: post #13

So... to drop the PM2.5 amount by 15%, this tower must be removing many many tons of particulate matter every day. How is it removed from the filters they speak of? How expensive is that to do? I have some questions about the practicality. On the other hand, I wonder if anyone's ever built a 100m placebo before. It could be a really interesting university study on the placebo effect in disguise.

> many many tons of particulate matter every day Let's do the math. Guidelines state that the limit on PM2.5 particulates is approximately 10 micrograms per cubic meter for an annual average. Xian, where the tower was installed, is currently ( http://aqicn.org/city/xian/ ) under 231 ug/m^3 of pollution. The tower is supposed to process 10 million cubic meters of air per day. 10^7 m^3 x 231 x 10^-6 g/m^3 x 10^-3 g/kg…

0.35 kg of particulate contamination removed per day; you rounded incorrectly, but the rest of your math is right.

There's the issue that it's probably removing nearly all of the particulates from the air it actually processes, say over 90%, which works out to 2.1 kg. It doesn't reduce the PM2.5 level in the area by 90%, but only by 15%, because it's only able to process some 16% of the air in its area during whatever the relevant time interval is, which seems like a good match to your 10%-per-day.

However, you got the volume of that area wrong: it's 10⁹ m³, not 10⁸ m³. That suggests that the natural lifetime of PM2.5 particulates is closer to a week than a day.

As for jhugg's question about how the filters are cleaned, a common way to remove particulates from flue gas or indoor spaces is using electrostatic precipitators, which are flat plates at a high voltage. The voltage sticks the particulates to the plates, and when the coating is thick enough, you close the valves to stop the gas flow and vibrate the plates to unstick the dust, and it falls out the bottom of the filter into a bucket (or, say, a truck). Other systems clean the plates with water (either spray or immersion) and possibly soap or lye.

Re: China builds ‘world’s biggest air purifier’ and it seems to be working

#58

Post by Overtonwindow »

Knufen wrote: post #6
reacharavindh wrote: post #5

I wish there was some technical background of what such a "purification tower" does. If they found a genuinely innovative way of purifying air and dumping the toxins and by products sensibly, that is mazing for all of us kudos to them! However, if they tried to push the problem away by shooting polluted air away and sucking in fresher air, then it sucks.

It says in the article that >"The hot air then rises through the tower and passes through multiple layers of cleaning filters." Meaning you just have to clean the filters

Those filters must be epic in size.

Re: China builds ‘world’s biggest air purifier’ and it seems to be working

#59

Post by briandear »

stelonix wrote: post #22
quadcore wrote: post #10

Side node: is China doing ok in terms of innovation? If yes, how come in such a regime? I would expect everything to be stuck in bureaucracy.

If anything, it goes to show representative democracy plus unrestrained capitalism is not the only way to run a modern, advanced civilization.

China a "modern, advanced civilization?" You've clearly never lived in China. China is all about the façade. And a MODERN, advanced civilization wouldn't be polluting their entire country like it was a tannery in 1758.

Taihu lake, near Suzhou, is practically radioactive. Fish in pretty much any freshwater within the entire country is toxic. I lived in China for 3 years or so and as soon as my son was born, we got the hell out -- it's a fun place, but no "modern, advanced" civilization operates like China. It's a country of mostly uneducated, superstitious peasants who suddenly got a lot of money and are kept in line with the threat of "re-education" or death. Even an artist has to fear for his life. http://aiweiwei.com

Then there's Lui Xiaobo.

Remember, this "modern, advanced" civilization still has Traditional Chinese Medicine as a "thing." It's a complete fraud with zero scientific basis: https://sciencebasedmedicine.org/retconning-traditional-chin...

This "modern, advanced" civilization is responsible for massive worldwide poaching to satisfy demand for quack TCM remedies: https://www.forbes.com/sites/jamesconca/2014/08/08/extinctio...

Really, powdered rhino horn? That's has the chemical composition of human fingernails -- and works just as "effectively."

They still do "postpartum confinement" http://edition.cnn.com/2015/08/11/china/chinese-postpartum-c... -- based on pretty much nothing but old wives tales and dangerous superstition.

Then there's the atrocious human rights record: https://www.hrw.org/world-report/2017/country-chapters/china...

I actually like China -- but the CCP isn't running a "modern, advanced civilization." They're the Beverly Hillbillies.

Re: China builds ‘world’s biggest air purifier’ and it seems to be working

#60

Post by briandear »

zxcvvcxz wrote: post #21
quadcore wrote: post #10

Side node: is China doing ok in terms of innovation? If yes, how come in such a regime? I would expect everything to be stuck in bureaucracy.

>If yes, how come in such a regime? I would expect everything to be stuck in bureaucracy. Haha you're funny... It's us in the West stuck with bureaucracy. China's growth is unprecedented, with a labor force that's becoming more educated and has always been very hungry for work (no beer or foosball needed). We're finally starting to see engineers and scientists trained here going back after they graduate. For a startu…

Less regulations? LOL.

https://www.lexology.com/library/detail.aspx?g=137e018c-80cb...

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