A massive tower designed to purify the air in its vicinity was recently constructed in the city of X’ian – the capital of China’s Shaanxi Province, which regularly suffers from enormous amounts of air pollution.
The project was launched in 2015 and construction was completed last year at a development zone in the Chang’an district.
Unlike many other air purification technologies, the 100-metre-tall tower is hollow, with no clever machinery nested inside to do the job.
Instead, the tower is surrounded by a greenhouse-like structure covering about half the size of a soccer field at the base, which heats up the air and sends it climbing up, where it eventually goes through a number of filters and is then released back into the atmosphere.
According to researchers from the Institute of Earth Environment at the Chinese Academy of Sciences, the effect of the tower, picked up by multiple monitoring stations built specifically for the project, is felt within the radius of approximately 10 km.
“The tower has no peers in terms of size (…) the results are quite encouraging”, said project leader Professor Cao Junji.
Junji claims the tower is capable of producing more than 10 million cubic metres of clean air every day, and was found to reduce the level of pollution by roughly 15 percent (bringing it back to “moderate”) on especially smog-heavy days.
Given that much of the city’s heating system relies on coal, pollution skyrockets in the winter, submerging it in a thick layer of smog. Luckily, even though sunlight is quite rare during winter in X’ian, the tower should still be operational thanks to the highly-absorptive coating of the glass below.
Furthermore, the new air purification monstrosity should work at a very low cost. “It barely requires any power input throughout daylight hours. The idea has worked very well in the test run,” said Junji.
Based on a patent application filed back in 2014, the research team plans to multiply the towers in other cities in China, some of which are set to be 500 metres high with a diameter of 200 metres wide, and exert their effect over an area of nearly 30 km – enough to cover a small city.
More information on the project is set to be released later this month.