New Delhi:Last week, an experimental tower over 100 metres (328 feet) high in northern China supposedly brought a noticeable improvement in air quality, at least,according to the scientist leading the project.
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.
A student studying environmental science at Shaanxi Normal University, also a few hundred metres from the tower, said the improvement was quite noticeable.
“I can’t help looking at the tower each time I pass. It’s very tall, very eye-catching, but it’s also very quiet. I can’t hear any wind going in or out,” she said. “The air quality did improve. I have no doubt about that.”
How does it work and is this efficient?
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.
The system works through greenhouses covering about half the size of a soccer field around the base of the tower.Polluted air is sucked into the glasshouses and heated up by solar energy. The hot air then rises through the tower and passes through multiple layers of cleaning filters.
The Xian smog tower project was launched by the academy in 2015 and construction was completed last year at a development zone in the Chang’an district. The purpose of the project was to find an effective, low cost method to artificially remove pollutants from the atmosphere. The cost of the project was not disclosed.
Not the only solution out there however
The Smog Free Tower that was built in Rotterdam a few years back, the brainchild of DaanRoosegaardeworks by drawing in polluted air from public spaces and passes it through filters, expelling air that is “75% more clean” than when it went in.
This creates areas around the towers of markedly increased breathe-ability. It can do this for 30,000 cubic meters of air per hour, with power consumption "as low as 1700 watts"and even collects the particles into smog “gems” that can be sold.
It works like an enormous air ionizer — it is an enormous air ionizer. It releases positively charged ions into the city air it collects, and these ions attach to the small particles in the air. A negatively charged electrode then draws in these positive ions, and the dangerous particles along with them.
Removing pollution directly at source
Scientists have figured out, for example, how to use biological excreta to power buses, rickshaws, and even homes. There’s technology now to turn restaurant grease into biofuel, ocean waste into shoes, and sewage into natural gas. Bill Gates has even proven that sewage can power the very system that turns sewage intodrinking water.
A Chinese artist grabbed international headlines when he paraded around Beijing with a vacuum and a brick made from the city’s notorious smog.“Nut Brother,” as he is known, vacuumed up more than 100 grams of fine particles from the air, mixed it up with clay, and turned it into a single brick.
An Indian, Anirudh Sharma has come up with a way to harvest black smoke and change it into printer ink. “If you capture that carbon and take it through a very simple chemical process, you can make really high-quality raw material that is important to printing and ink industries,” said Anirudh referring to smoke coming from cars.
The black, powdery substance left behind by the after the carcinogens and impurities are removed is what Sharma calls “black gold.” Mixed with a bit of alcohol and oil, it can turn into a cheaper alternative to traditional ink.
Handheld devices will be attached to cars to capture the carbon. For every six miles the car travels, enough carbon is produced to generate two cartridges of ink.“We are cleaning the environment by not releasing the carbon that would otherwise enter into the lungs of people,” he says.
Another team of scientists in San Francisco is working to turn methane gas into fish food. Their weapon of choice: Methylococcuscapsulatus, a type of microbe that feeds on methane from decomposing vegetables. And another team at Virginia Tech have unlocked a key aspect of how bacteria turn sewage into electricity.
References
www.citylab.com
www.scmp.com
www.treehugger.com
www.techspot.com