China has built the ‘world’s largest air purifier’ to battle smog
Andrew Lockley
China has built the ‘world’s largest air purifier’ to battle smog
Rob Smith, Formative Content
Scientists at China’s Institute of Earth Environment have constructed what they say is the world’s largest air purifier in the northern city of Xian.
The experimental smog-sucking tower stands at over 100 metres tall and is designed to improve air quality in the city, where standards regularly fall short of expectations set by the World Health Organization.
The tower has already brought a noticeable improvement in air quality across an area of 10 square kilometres, according to a report in the South China Morning Post.
Lead researcher Cao Junji says the tower is capable of producing more than 10 million cubic metres of clean air per day, adding that on severely polluted days smog is reduced to “moderate levels”.
To monitor the tower’s impact, Junji’s team placed pollution monitoring stations in the surrounding area, discovering that levels of PM2.5 — the fine particles in smog considered most harmful — fell 15% during times of heavy pollution, compared to average.
How it works
The system comprises a series of specially-adapted greenhouses situated at the base of the tower, which suck in polluted air and heat it using solar energy.
The air then rises through layers of cleaning filters before being released into the atmosphere. A full assessment of the tower’s performance is expected later this year, with the researchers hoping to build a fully-functioning tower around five times larger thereafter.
The Xian tower experiment is similar to the Smog Free Project, created by Dutch artist Daan Roosegaarde in 2016 as a means of purifying Beijing’s air.
That project consists of two parts. First, a seven-metre-tall tower sucks up polluted air, and cleans it at a nano-level. Second, the carbon from smog particles is turned into diamonds.
More smog towers are being produced for parks and playgrounds across China’s cities. Roosegaarde says air in these areas will be 70–75% cleaner than the rest of the city.
Clean future
This is particularly good news for a country that has notoriously high levels of air pollution.
China’s share of the global emissions mix jumped from 5.7% in 1973 to 28.1% in 2016. This is due largely to its unrivalled appetite for coal.
According to the latest Key World Energy Statistics report by the International Energy Agency, China was the world’s largest producer and importer of coal in 2016.
And while China was not among the 20 countries that agreed to phase out coal by 2030 at last year’s COP23 climate talks, it is attempting to reduce its carbon footprint.
For example, China recently announced it would scrap plans to build 85 coal-fired plants.
And last year the country introduced anti-pollution measures across 28 cities. The plan, which includes curbing production in heavy industries, is designed to cut PM2.5 concentrations by at least 15% year-on-year.
China has also increased its investment in clean energy, from $7.5 billion in 2005 to more than $101 billion a decade later. This is in addition to investing $44 billion in overseas clean energy projects last year, according to the Institute for Energy Economics and Financial Analysis.
In comparison, the European Union invested $39.9 billion in clean energy in 2015.
Renaud de RICHTER
This "small" tower prototype aims to remove PM2.5 and PM10 by filtration, but in another link in Chinese, it is said that they coated photocatalyst in order to remove VOCs and NOx.
(google translation is not bad for this: 据悉，氮氧化物（NO2）和挥发性有机物（VOCs）是形成臭氧等二次污染物的重要前体物，对城市灰霾形成具有重要影响，
而集热棚表面的光催化作用是一种由太阳光驱动，发生于界面间的光致氧化还原反应，能够直接降解和转化NO2等低浓度空气污染物和有机物，因此通过光催化技术降解后的空气可直接起到进化空气的作用。 )
http://ec.europa.eu/environment/integration/research/newsalert/pdf/nitrous_oxide_removed_atmosphere_generation_renewable_energy_476na3_en.pdf
Or this one to answer to a GR question: https://www.sciencedirect.com/science/article/pii/S1364032112005680 ;
https://www.sciencedirect.com/science/article/pii/S1750583616300858
Best regards,
China builds ‘world’s biggest air purifier’ (and it seems to be working)
A 100-metre high air purification tower in Xian in Shaanxi province has helped reduce smog levels in the city, preliminary results suggest
An experimental tower over 100 metres (328 feet) high in northern China – dubbed the world’s biggest air purifier by its operators – has brought a noticeable improvement in air quality, according to the scientist leading the project, as authorities seek ways to tackle the nation’s chronic smog problem.
The tower has been built in Xian in Shaanxi province and is undergoing testing by researchers at the Institute of Earth Environment at the Chinese Academy of Sciences.
The head of the research, Cao Junji, said improvements in air quality had been observed over an area of 10 square kilometres (3.86 square miles) in the city over the past few months and the tower has managed to produce more than 10 million cubic metres (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.
renaud.derichter
Much bigger devices are expected:
Le mardi 20 février 2018 21:08:06 UTC+1, renaud.derichter a écrit :
For our Chinese colleagues: Happy Chinese New Year! Happy the Dog Year!
This "small" tower prototype aims to remove PM2.5 and PM10 by filtration, but in another link in Chinese, it is said that they coated photocatalyst in order to remove VOCs and NOx.
(google translation is not bad for this: 据悉，氮氧化物（NO2）和挥发性有机物（VOCs）是形成臭氧等二次污染物的重要前体物，对城市灰霾形成具有重要影响，
而集热棚表面的光催化作用是一种由太阳光驱动，发生于界面间的光致氧化还原反应，能够直接降解和转化NO2等低浓度空气污染物和有机物，因此通过光催化技术降解后的空气可直接起到进化空气的作用。 )The full scale tower filtration devices are supposed to be 500 m high and be able to filter 23 km3 of air per day each one. For Beijing the effects of a total of 8 towers have been modeled.An article in Nature by David Cyranoski is expected soon.Meanwhile you can read the following ones:
http://ec.europa.eu/environment/integration/research/newsalert/pdf/nitrous_oxide_removed_atmosphere_generation_renewable_energy_476na3_en.pdf
(open access) https://www.sciencedirect.com/science/article/pii/S0360128516300569 ;
Or this one to answer to a GR question: https://www.sciencedirect.com/science/article/pii/S1364032112005680 ;
https://www.sciencedirect.com/science/article/pii/S1750583616300858
Best regards,Renaud2018-02-20 18:33 GMT+01:00 Leon Di Marco <len...@gmail.com>:China builds ‘world’s biggest air purifier’ (and it seems to be working)
A 100-metre high air purification tower in Xian in Shaanxi province has helped reduce smog levels in the city, preliminary results suggest
An experimental tower over 100 metres (328 feet) high in northern China – dubbed the world’s biggest air purifier by its operators – has brought a noticeable improvement in air quality, according to the scientist leading the project, as authorities seek ways to tackle the nation’s chronic smog problem.