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 <https://view.inews.qq.com/a/20180118A0H1AP00>, 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 <https://www.sciencedirect.com/science/article/pii/S0048969718300834>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/newsale rt/pdf/nitrous_oxide_removed_atmosphere_generation_renewabl e_energy_476na3_en.pdf (open access) https://www.sciencedirect.com/science/article/pii/S036012851 6300569 ; 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 <http://ec.europa.eu/environment/integration/research/newsalert/pdf/nitrous_oxide_removed_atmosphere_generation_renewable_energy_476na3_en.pdf> Best regards, Renaud 2018-02-20 18:33 GMT+01:00 Leon Di Marco <[email protected]>: > 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. > SCMP TODAY: INTL EDITION > Get updates direct to your inbox > E-mail * > By registering you agree to our T&Cs > <http://www.scmp.com/terms-conditions> & Privacy Policy > <http://www.scmp.com/privacy-policy> > > 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. > > -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout.
