{"id":5495,"date":"2018-03-02T17:41:54","date_gmt":"2018-03-02T09:41:54","guid":{"rendered":"https:\/\/smartairfilters.com\/?p=5495"},"modified":"2020-07-15T11:57:16","modified_gmt":"2020-07-15T03:57:16","slug":"xian-unveils-smog-fighting-tower-work","status":"publish","type":"post","link":"https:\/\/smartairfilters.com\/en\/blog\/xian-unveils-smog-fighting-tower-work\/","title":{"rendered":"Xi\u2019an Unveils Smog-Fighting Purifier Tower, but Does It Work?"},"content":{"rendered":"

One group of scientists on the south side of Xi\u2019an are fighting back against\u00a0<\/span>Xi\u2019an\u2019s rising PM2.5<\/a>, and they did so in true China style \u2014\u00a0<\/span>by building something big<\/a>, a huge air purifier tower to be precise. But locals are left to wonder, does it actually work?\u00a0<\/span><\/p>\n

 <\/p>\n

\"\"<\/p>\n

 <\/p>\n

The air filtering tower might be coming at a good time. 2017 was a bad year for Xi\u2019an\u2019s air. While\u00a0<\/span>the rest of China cut its PM2.5 levels in 2017<\/a>, Xi\u2019an’s air pollution levels actually\u00a0<\/span>got worse<\/a>.<\/p>\n

 <\/p>\n

\"\"<\/p>\n

 <\/p>\n

That makes Xi\u2019an China\u2019s current PM2.5 \u201cchampion\u201d (among major cities) and a bad place to be an air-breather.<\/p>\n

\"\"<\/p>\n

Prior failures give reason to be pessimistic<\/h3>\n

This isn\u2019t the first project in China to create a huge air purifier to try to purify outdoor air. Dutch artist Daan Roosegaarde built an ionizing tower in Beijing and Tianjin, claiming it would clean air the air pollution outdoors.<\/p>\n

 <\/p>\n

\"\"<\/p>\n

 <\/p>\n

Yet independent tests of the air filter tower found it\u00a0<\/span>was not providing clean air<\/a>\u00a0<\/span>even within 10 meters of the tower. Even a careful look at the team\u2019s own modeling estimated only a 20% drop among large particles (PM10, not PM2.5), assuming zero wind, and only up to 20 meters from the tower. Thus, the tower is more art than science.<\/p>\n

 <\/p>\n

\"\"<\/p>\n

Is the Xi\u2019an Tower Just as Much Smoke and Mirrors?<\/h3>\n

Given the Dutch artist\u2019s failure, Xi\u2019an residents can be forgiven for being skeptical. However, the Xi\u2019an tower works completely differently from the artist\u2019s towers.<\/p>\n

 <\/p>\n

\"\"<\/p>\n

 <\/p>\n

First, the sun heats up the air inside a large greenhouse. Next, that warm air rises through a chimney and passes through huge air filters. Reports don\u2019t say what type of filters those are.<\/p>\n

 <\/p>\n

\"\"<\/p>\n

 <\/p>\n

So does it work? Without data, we can only make an educated guess.<\/p>\n

Pro:\u00a0<\/strong>The tower uses a different process from earlier failed towers and doesn\u2019t use ionization (the science behind\u00a0<\/span>why ionizers are largely ineffective<\/a>).<\/p>\n

Con #1:<\/strong>\u00a0<\/span>Greenhouses work the best when the sun is strong. Smog is worst in Xi\u2019an in the winter, when the sun is the weakest.<\/p>\n

\"\"<\/p>\n

Con #2:<\/strong>\u00a0<\/span>The tower would have to move a LOT of air to have any noticeable impact.\u00a0<\/span>The team claims<\/a>\u00a0<\/span>the massive air purifier tower cleans 10 million cubic meters a day. That\u2019s a big number, but the team is analyzing a\u00a0<\/span>10 square kilometer<\/a>\u00a0<\/span>area. Even at the\u00a0<\/span>smallest air mixing height of 100 meters<\/a>, the tower would have to clean 1 billion cubic meters of air. Thus, the tower would be cleaning only 1\/100th\u00a0<\/sup>of the air. And that assumes the air doesn\u2019t move or receive new pollution.<\/p>\n

Bottom Line<\/div>
Bottom Line<\/div>
<\/p>\n

Xi\u2019an\u2019s smog tower should work in principle, but rough calculations suggest it\u2019s unlikely to have a major impact. We hope to see real-life test data. <\/div>

Smart Air<\/div><\/div>\n

Help Solve This Question and Collect\u00a0<\/span><\/strong>Independent Test Data!<\/span><\/strong><\/h3>\n

The data nerds at Smart Air would love to test the tower! Do you own a particle counter and live in Xi\u2019an? If so, email Joseph at\u00a0joseph@smartairfilters.cn<\/a><\/span>, and we\u2019ll coordinate tests, analyze the data, and publish the results.<\/p>\n

 <\/p>\n

\"\"<\/p>\n

 <\/p>\n

Breathe safe!<\/p>","protected":false},"excerpt":{"rendered":"

One group of scientists on the south side of Xi\u2019an are fighting back against\u00a0Xi\u2019an\u2019s rising PM2.5, and they did so in true China style \u2014\u00a0by building something big, a huge air purifier tower to be precise. But locals are left to wonder, does it actually work?\u00a0     The air … <\/p>\n

Read more<\/a><\/p>\n","protected":false},"author":1035,"featured_media":5726,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_relevanssi_hide_post":"","_relevanssi_hide_content":"","_relevanssi_pin_for_all":"","_relevanssi_pin_keywords":"","_relevanssi_unpin_keywords":"","_relevanssi_related_keywords":"","_relevanssi_related_include_ids":"","_relevanssi_related_exclude_ids":"","_relevanssi_related_no_append":"","_relevanssi_related_not_related":"","_relevanssi_related_posts":"","_relevanssi_noindex_reason":"","footnotes":""},"categories":[17,262],"tags":[],"class_list":["post-5495","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-air-pollution","category-reviews","resize-featured-image"],"acf":[],"_links":{"self":[{"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/posts\/5495","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/users\/1035"}],"replies":[{"embeddable":true,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/comments?post=5495"}],"version-history":[{"count":8,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/posts\/5495\/revisions"}],"predecessor-version":[{"id":11525,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/posts\/5495\/revisions\/11525"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/media\/5726"}],"wp:attachment":[{"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/media?parent=5495"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/categories?post=5495"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/tags?post=5495"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}