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China Earth Science

China Builds 'World's Biggest Air Purifier' That Actually Works (scmp.com) 138

Posted by BeauHD from the unconventional-methods dept.
The South China Morning Post shares an update on the status of an experimental tower in northern China, dubbed the world's biggest air purifier by its operators. According to the scientist leading the project, the tower -- which stands over 328 feet (100 meters) tall -- has brought a noticeable improvement in air quality. From the report: The head of the research, Cao Junji, said improvements in air quality had been observed over an area of 10 square kilometers (3.86 square miles) in the city over the past few months and the tower has managed to produce more than 10 million cubic meters (353 million cubic feet) of clean air a day since its launch. Cao added that on severely polluted days the tower was able to reduce smog close to moderate levels. The system works through greenhouses covering about half the size of a soccer field around the base of the tower. Polluted air is sucked into the glasshouses and heated up by solar energy. The hot air then rises through the tower and passes through multiple layers of cleaning filters. The average reduction in PM2.5 -- the fine particles in smog deemed most harmful to health -- fell 15 per cent during heavy pollution. Cao said the results were preliminary because the experiment is still ongoing. The team plans to release more detailed data in March with a full scientific assessment of the facility's overall performance.
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China Builds 'World's Biggest Air Purifier' That Actually Works More

China Builds 'World's Biggest Air Purifier' That Actually Works

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  • Grrr. (Score:3, Insightful)

    by Anonymous Coward on Tuesday January 16, 2018 @06:01PM (#55942195)

    Something seems wrong about this.
    We shouldn't be purifying air, we should not be polluting in the first place.
    This'll just allow people to continue polluting with natural gas to generate electricity (fastest growing fossil fuel electricity producer)

    • Re: Grrr. (Score:5, Insightful)

      by Anonymous Coward on Tuesday January 16, 2018 @06:24PM (#55942331)

      How much of a tree hugger do you have to be to complain about a solar powered pollution reducer?

      • Re: (Score:3, Insightful)

        by Anonymous Coward

        Wait, doesn't that description fit trees themselves?

    • How so? This device is designed to filter out small particles not CO2.

      Natural gas actually is "clean" emissions wise, with very little other than CO2 and water being released. Small participates are not produced when burning Natural Gas, unlike fuels like coal and oil. So this "filter" doesn't help. Also "clean coal" involves scrubbers that filter out very small particles from the combustion emissions, then treat the rest to remove the bulk of the remaining pollutants other than CO2.

      Here in the USA, we

      • Re: (Score:1)

        by Anonymous Coward

        Devices like this would be largely unnecessary if there were scrubbers attached directly to the plants and devices that are emitting the particles in the first place.

        Once the particles are emitted it becomes much more challenging to recapture them.This is at best a half measure before the central government can properly crack down on businesses that are breaking the pollution regulations.

        • Attach a scrubber to every car, truck, semi, train and plane, attach one to every home, and building heating system as well as every industrial plant and refinery? This is not just a dirty coal plant problem.

          • Re: (Score:2)

            by nasch ( 598556 )

            Attach a scrubber to every car, truck, semi, train and plane, attach one to every home, and building heating system as well as every industrial plant and refinery?

            It's a difference of degree. All those things emit some particulates (with the possible exception of "building heating system", I'm not sure what you're referring to there) just not nearly in the quantities of a dirty coal plant. The difference is obvious if you look at recent photos of cities such as London or LA compared to Beijing or Shanghai. Also compare English cities of today with 30 or 40 years ago when they burned a lot of coal.

            • A Building heating system is just that, the Heating or HVAC system in every home, business, government and other building designed to keep the interior at temperatures comfortable for the human occupants. Except for purely electric systems (which aren't that common) they burn something, most burn NG, a few propane, fuel oil or wood. These all emit PM2.5 particulate emissions, some are better than others but they still each add a small amount. Add in all the vehicles, even with the clean modern exhaust sy

          • Those are called catalytic convertors. They function well enough, like the tower does and not 100% removal.

            • Cats convert incomplete oxides to more complete, eg carbon monoxide to carbon dioxide. They don't do anything for particulates.

      • "Natural gas actually is "clean" emissions wise, with very little other than CO2 and water being released."

        You are forgetting about the, albeit small amounts of, sulfur, mercury, and particulates with moderate amounts of nitrogen oxides. Certainly much cleaner than burning gas, but not completely clean either and should not be used as a benchmark as such.

        • Re:Grrr. (Score:4, Informative)

          by bobbied ( 2522392 ) on Tuesday January 16, 2018 @08:13PM (#55943011)

          Properly pre-processed, such pollutants are extremely limited compared to coal or liquid fuels.

          For example... Sulfur dioxide from coal is 2.591 lbs/MMBtu where natural gas emits 0.001, Nitrogen oxides are reduced from 0.457 to 0.092, and where coal emits 0.000016 of mercury, natural gas emits none. https://en.wikipedia.org/wiki/... [wikipedia.org]

          Natural Gas also emits less CO2 than coal. So all around it's a winning choice until other sources of energy come on line.

          Personally, I would advocate that we use it instead of diesel and gasoline as a motor fuel because of this reduction in emissions as it is able to be used in *existing* internal combustion engines with little modification and we in the USA have a bunch of Natural Gas...

          • We have a bunch of natgas from fracking, that's no solution.

            • Why not?

              Actually, Natural Gas is only a temporary solution, no matter how you slice it. I'm just suggesting that it might be a good sort term solution as a viable motor fuel that would give us better emissions for the same work with a minimum of fuss and trouble.

              • I'm just suggesting that it might be a good sort term solution as a viable motor fuel that would give us better emissions for the same work with a minimum of fuss and trouble.

                Existing refineries can be jiggered to make green diesel out of algal lipids, butanol can be made fairly cheaply to replace gasoline, and we should simply proceed with electrification if we want to improve emissions. (In the short term, we can also add heated catalysts, which drastically improve cold-start emissions; these go hand in hand with hybrid systems, which provide the power to heat the catalyst.) Fracking is bad for water supplies, and increasing natgas production means doing more fracking, so it's

                • Environmental stupidity on display...

                  So, you somehow think we can just cut over to "green" and the resulting cost and economic impacts be dammed? Don't be stupid. Take what you can easily get. Once you have that, THEN make your case for the next incremental step. Avoid the adverse economic impacts happening all at once and you are more likely to actually make progress.

                  • Environmental stupidity on display...

                    Thanks for the warning, sport.

                    So, you somehow think we can just cut over to "green" and the resulting cost and economic impacts be dammed?

                    Name the cost and economic impacts of the move I described.

                    Take what you can easily get.

                    That's what this is. It's actually easier than natgas conversion, because you don't have to do anything to the vehicles. Green diesel is a 1:1 replacement for petro diesel (it doesn't cause any of the problems that biodiesel causes) and butanol is a 1:1 replacement for gasoline which only causes the same problems that supplementing fuel with ethanol causes.

                    • Environmental stupidity on display...

                      Thanks for the warning, sport.

                      So, you somehow think we can just cut over to "green" and the resulting cost and economic impacts be dammed?

                      Name the cost and economic impacts of the move I described.

                      There isn't enough capacity for diesel fuel production from things like algae like you suggested and it is more expensive by multiple times. If we suddenly have $8.00/gal diesel fuel costs, it's going to be a HUGE shock to the economy which pretty much depends on diesel fuel to transport goods. Yes, biodiesel isn't $8/gal now, but if you just yank fossil fuels off the market, it will be every bit of that and more overnight.

                      There is also the farce that moving to electric cars is somehow better for the env

        • Re: (Score:2)

          by nasch ( 598556 )

          You are forgetting about the, albeit small amounts of, sulfur, mercury, and particulates with moderate amounts of nitrogen oxides.

          Or you're forgetting he said "very little" not "nothing".

      • We have? Many areas struggle at various times of year to meet EPA 2.5 particle standards. If actually as effective as this claims the Wasatch front area of Utah, which is in a bowl that traps pollutants via inversions between storms every winter, would greatly benefit from this, as would the LA area with it's smog issues. We have cleaned up many of the pollution problems but 2.5 particulate pollution is still a very substantial problem.

        • We have? Many areas struggle at various times of year to meet EPA 2.5 particle standards. If actually as effective as this claims the Wasatch front area of Utah, which is in a bowl that traps pollutants via inversions between storms every winter, would greatly benefit from this, as would the LA area with it's smog issues. We have cleaned up many of the pollution problems but 2.5 particulate pollution is still a very substantial problem.

          As you point out, we are not perfect.. However, as you indicate, things are MUCH better than the 70's because we have made huge strides. My point here is that China isn't reducing the problem at it's source, where it is the most effective and cheapest to fix.

    • A lot of the pollution in Beijing comes from the Gobi Desert [wikipedia.org]. It is a fairly regular thing for fine desert dust [independent.co.uk] to be an appreciable amount of the pollution. That seems worthwhile in terms of filtering - and it's a 100% natural source of "pollution" (which is more than just man-made stuff).

      • Funny how the amount of 'desert dust' has increased at the same time China built a load heavy industrial plants.

      • Re:Grrr. (Score:4, Interesting)

        by Zontar The Mindless ( 9002 ) <plasticfish@info.gmail@com> on Tuesday January 16, 2018 @07:45PM (#55942845) Homepage

        You've never been to Beijing, have you? The dome of smog surrounding the city is visible from 100 km away, and it's not caused by a big pile of dirt from the Gobi just deciding it wants to live there.

        • Re:Grrr. (Score:4, Interesting)

          by LynnwoodRooster ( 966895 ) on Tuesday January 16, 2018 @09:44PM (#55943427) Journal
          I lived in Shanghai for 6 years, and have been traveling to China (and living, at least 3 months each year) for 20. I've been to Beijing countless times. Yes, a lot of it is smog - but when the wind blows out of the West, a lot of the brown you see is actually dust from the Gobi. Much like we get sand in Hollywood Beach, CA and you get dust in your house around harvest time near any wheat farm.

          • Yeah dust. As a general clue if your pollutant is big enough to settle in your house and natural enough that it doesn't cause cancer then it shouldn't be compared to smog.

            Dust storms and the cloud that rises from the city centre are two very different things.

        • The person who modded my post as a troll need only look out the window as he's flying into Beijing International. Best time is about an hour prior to landing.

          I absolutely guarantee that he will see the GIANT FUCKING DOME OF SMOG lying atop the city. It looks for all the world like a big Jello salad made with used mop water.

          He will then be welcome to come back and apologise.

      • Re: (Score:1)

        by Anonymous Coward

        A lot of the pollution in Beijing comes from the Gobi Desert [wikipedia.org]. It is a fairly regular thing for fine desert dust [independent.co.uk] to be an appreciable amount of the pollution. That seems worthwhile in terms of filtering - and it's a 100% natural source of "pollution" (which is more than just man-made stuff).

        Natural in the sense of a result of actual physics? Sure. As a result independent of human behavior? Nope, not 100%, in fact, as various ill-advised land management [nytimes.com] usages in the Gobi Desert have had severe results on the stability of the soil surface, much the way the Dust Bowl did back in the 1930s or the poor cultivation techniques in Africa(some also fostered by China). Hence the need for a long-standing program [wikipedia.org] to reverse the problem created by human acts, though of course, said program may not be

      • You should learn the difference between smog and dust storms. Both are things. One of them is a thing that smells horrible and causes cancer.

      • Man made de forestation played a great part in the expansion of the Gobi Desert to the point where it has become an environmental hazard.

  • How long would the filters last?

    Essentially they have build a big fan to force the air through filters.

    • How long would the filters last?

      There are ceramic filters [corning.com] that can be baked to burn the soot collected. If I were to build this, it's what I would use. No point cleaning up pollution by creating even more pollution.

  • ... but I, for one, am happy, whenever there probably seems to be a piece of good news out there.

    It's certainly better news then most other things we hear, even with all the things wrong I'm sure everyone will soon have come up with.
    (And I'm saying that as the official godking of calling the world shit. I was born in that mood, molded by it. We played "end of the world in four steps" as children. I didn't see good times until I was already a man.)

  • One of the most harmful pollutants is NOx. It's very hard to filter out, as it's a gas. How does this system deal with that?

    • Re: (Score:2)

      by tepples ( 727027 )

      The featured article doesn't mention nitrogen oxides. But not all research projects can target all noxious pollutants. This one happened to target particulates, ending up with a successful particulate filter with solar thermal powered circulation.

    • Re: (Score:2)

      by fubarrr ( 884157 )

      Ammonia solution showers

  • I'm already convinced. Put this up everywhere.

  • Seems like the Air scrubbers out of the SimCity future technology pack

  • The system works through greenhouses covering about half the size of a soccer field around the base of the tower.

    How many football fields is that?

    • Soccer (football) is 7140 m^2. Football (American football) is 5351.2 m^2. Half of Soccer (football) is 3570 m^2, that makes 3570 / 5351.2 or 2 / 3 of a Football (American football) field.
  • What do they do with the used filters?

  • China Builds 'World's Biggest Air Purifier' That Actually Works

    Whenever I see stuff like this, I always have questions:

    • Is there a bigger air purifier that doesn't work?
    • Where is the second biggest air purifier?

  • So (Score:4, Funny)

    by IWantMoreSpamPlease ( 571972 ) on Tuesday January 16, 2018 @07:48PM (#55942873) Homepage Journal

    No firing 10mm explosive tip caseless under the primary heat exchangers, right?

  • Math (Score:5, Insightful)

    by Solandri ( 704621 ) on Tuesday January 16, 2018 @08:21PM (#55943051)

    improvements in air quality had been observed over an area of 10 square kilometers (3.86 square miles) in the city over the past few months and the tower has managed to produce more than 10 million cubic meters (353 million cubic feet) of clean air a day since its launch.

    10 million cubic meters spread over 10 square kilometers is (10 million m^3) / (10 km^2) = 1 meter. So over such a wide area, this thing is only cleaning a 1 meter thick layer of air.

    • It's one meter of cleaned air - but it is "raining" from above. It's not being stacked in bricks of air, from the ground up.

      You know how rainfall is measured in millimeters per square meter?
      Well, imagine how much rain would have to fall for 1000 millimeters of it to accumulate on the ground.
      Now imagine instead of it all falling down, all that rain just kinda hanging in the air.

    • Re: (Score:2)

      by AmiMoJo ( 196126 )

      That sounds about right for the results they are getting - an average 15% reduction in PM2.5 over the area at ground level. Considering they managed to do that with just one of these things they should be able to get pretty good results with a few of them spread around a city.

    • Re: (Score:2)

      by jbengt ( 874751 )
      353 million cubic feet of air per day seems like an awfully small number for a city. I've been involved in projects (for building HVAC) with the capacity to handle well over 500 million cubic feet of air per day, and that's just for one building, not a city. Granted, those systems might not 'purify' the air, but many of them have had high efficiency particulate arrestance filters and/or activated carbon filters. To put it the way Solandri did, HVAC systems can typically turn over the air in occupied spac

  • Bigger Picture (Score:4, Interesting)

    by mutantSushi ( 950662 ) on Tuesday January 16, 2018 @09:00PM (#55943241)
    So to have significant effect, such a system would need to be installed on many flat-topped buildings in urban areas, or open ground. If you're going to do that, why not install solar power generators in the same places, which reduce need for dirty power generation? The system is de facto using clean power generation potential for air filtering, albeit in efficient manner (due to direct utilization of solar thermal energy), but I question it's total utility value. China is already pushing electric cars etc heavily so that source is not a long term problem.

    I would supposition that plant based air cleaning systems, whethe normal plants like http://mashable.com/2017/02/09... [mashable.com] or moss like https://futurism.com/4-citytre... [futurism.com] can be installed even more places, even filling vertical walls, effect not dependent on large single areas to support 'chimney' etc, and actively clean the air in even more ways, as well as adding oxygen.

    Although on the other hand, the chimney filter system can very well be applied where heat chimneys already inherently serve climate control cooling function for buildings, and designing buildings with this approach in mind reduces need for air conditioning etc thus reducing electric consumption.

    • Re: (Score:2)

      by nasch ( 598556 )

      If you're going to do that, why not install solar power generators in the same places, which reduce need for dirty power generation?

      That would do nothing about the pollution already in the air. I have no idea how long particulates stick around though, maybe it would clear up quickly. The Chinese are going big on solar as well though.

    • If you're going to do that, why not install solar power generators in the same places, which reduce need for dirty power generation?

      Because far away power plants aren't the cause of inner city smog, and solar panels aren't the solution them.

    • Re: (Score:2)

      by AmiMoJo ( 196126 )

      A lot of the pollution in China is from industry and construction.

      Stuff is being built everywhere, and I really do mean everywhere. It's hard to find somewhere that doesn't have some construction going on nearby. And they don't do it inside a giant tent or make much effort to keep it clean and tidy either, so it produces a lot of dust and soot.

  • Why not use water or some other method that won't need constant filter replacement and create junk. The water could be reused until it evaporates away and leaves solid waste material. You could even use the water to cool something as it does it's job.

  • 15 million people with handheld fans... (Score:3)

    by fatp ( 1171151 ) on Wednesday January 17, 2018 @01:04AM (#55944045) Journal
    China has proposed to make 15 million people with handheld fans to blow smog away .
    While this may not be called 'build', it must world's biggest air purifier.
    http://shanghaiist.com/2017/11... [shanghaiist.com]
  • Scientists do all kinds of different experiments and I'm glad they did this and it's operational. However, I think it obvious that since the government has such tight control, they are swiftly implementing actions to go after the sources in the manner that won't kill the economy. What I don't get is that just creating the jobs to put the additional filters on coal plants is beneficial so things like that should be happening as intermediate steps. I was shocked the other day when I saw the article how they
  • So, we invest millions on tearing down old smog producing chimneys to spend millions putting up new smog reducing chimneys....

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