In an attempt to fight against air pollution, China has constructed an experimental air purifier tower, touted to be the world’s biggest at a height of over 100 meters (328 feet). This $2 million tower, is dubbed as the world’s biggest air purifier by its operators and 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 is built in Xian in Shaanxi province and is undergoing testing by researchers at the Institute of Earth Environment at the Chinese Academy of Sciences. Given some positive findings, the researchers behind the project say they hope to build an even taller air-purifying tower in Xi’an, and possibly in other cities around China.
Lead researcher Cao Junji says the tower is much more 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”.
Since Xian highly relies on coal for heating, smog can become exceptionally thick and harmful during the winter season. Despite the lower level of solar energy available during the winter, a special coating on the tower’s greenhouses allows it to absorb what is available more efficiently and continue to pull smog all year long. 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.
According to a report, smog has claimed over 1.8 million deaths in China, and scientists have worked hard to combat the threat and built a nearly 328 feet tall air purifier, to fight the deadly pollution in the country.
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. At the tower’s base, there is also a large network of greenhouses. Polluted air is brought into these glass rooms where it’s heated by trapped solar energy. The hot air naturally rises, moving upwards through the tower’s many sets of cleaning filters.
While there have been other similar smog-removing towers, many of which were powered by coal-fueled electricity, the Xian tower is unique in its very limited electricity needs. “It barely requires any power input throughout daylight hours. The idea has worked very well in the test run,” said Cao. While locals have marveled at the tower’s size, it is in fact a miniature version of smog-removing towers that Cao and his team hope to install throughout China’s dense, massive cities. The full-size version could reach as high as 500 meters (1,640 feet) while the surrounding greenhouses could cover nearly 30 square kilometers (11.6 square miles). Researchers have already begun planning a 1,640-foot-tall version capable of cleaning the air for a small city.
Around the globe, air pollution is the single biggest health risk to city-dwellers.The city of Beijing recently announced a plan to replace 67,000 gas-fueled taxis with electric ones, and has previously worked with the Dutch designer Dan Roosegarde on a 23-foot-tall smog-sucking tower as well as air-purifying bikes.
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.