The world's largest air purifier sucks in smog and turns it

The air we breathe is not as clean as it once was – and in many cases, it is getting worse.

According to a recent study by researchers at UC Berkeley, smog kills about4,000 people every day in China. And in the US about 4 in 10 people live in counties that have unhealthy levels of either ozone or particle pollution, according to the American Lung Association.

To help clean up our air and make it breathable again, Dutch designer Daan Roosegaarde created a 23-foot (7-metre) tall air purifier called the Smog Free Tower.

The tower-like device essentially sucks up smog like a vacuum from the top and then releases the filtered air through its six-sided vents. It can clean more than 30,000 cubic metres of air per hour and runs on 1,400 watts of green energy.

The project, which was funded on Kickstarter, took Roosegaarde about three years of research and development, but he is finally showing off the prototype of his giant air purifier this week in Rotterdam. According to Roosegaarde's website, the air purifier was specifically created to be used in public parks.

Roosegaarde describes how the tower works on its Kickstarter page:

"By charging the Smog Free Tower with a small positive current, an electrode will send positive ions into the air. These ions will attach themselves to fine dust particles.

A negatively charged surface – the counter electrode – will then draw the positive ions in, together with the fine dust particles. The fine dust that would normally harm us, is collected together with the ions and stored inside of the tower. This technology manages to capture ultra-fine smog particles which regular filter systems fail to do."

But the well-designed air purifier doesn't just clean up smog, it can also be used to make fine jewellery.