Can ‘air purification towers’ solve India’s air pollution problem – CNN.co.jp
‘Verto’ prototype installed in a park in New Delhi, India / Avesh Gaur
2023.07.02 Sun Posted at 14:06 JST
(CNN) Since last summer, well-designed filtration “towers” have been quietly cleaning the air around a park in India’s capital, New Delhi, one of the world’s most polluted cities. Dubbed ‘Verto’, the 5.5-meter-tall facility filters 600,000 cubic meters of air a day (equivalent to 273 hot air balloons), removing nitrogen dioxide (NO2) and reducing levels of dangerous fine particulate matter in New Delhi’s Sundar Nasri Park .
After collecting prototype data, the architects involved in designing the tower believe the project could be scaled up to clean the air in large public spaces, neighborhoods or even entire cities.
Designed by Symbiosis, an architecture firm with offices in India and Germany, the tower consists of five stacks of air-filtering “cubes” within a geometric shell. According to office co-founders Amit and Britta Nobel Gupta, the device is fan-driven and has a radius of 200-500 meters indoors and 100-100 meters outdoors, depending on wind speed and openness. It can purify the air at a distance of 350 meters.
The surface of the tower is carefully designed to maximize the amount of air drawn into the filter / Avesh Gaur
“As the (prototype) results met our expectations, we will start discussions with government officials on further installation of the tower,” Amit said in a video call from New Delhi, referring to potential Uzbekistan, France and New Zealand installations. Worker. Said he was talking to a customer. Studio Symbiosis says a US construction firm is considering ordering up to 40 towers to deal with dust and fines on construction sites.
“I think you can put it in parks and squares where people are spending quality time outside,” Britta said, adding that if you put it where the homeless sleep, it’s “very OK.” That’s helpful.
Verto is derived from the Latin word “vertente” (to rotate), and its twisted shape is designed to force as much air as possible across the surface of the unit, sucking it into the filter and out. Using filters from German filter manufacturer Mann und Hummel, the architects at Studio Symbiosis focused on creating the most efficient shape for the tower, using digital models to simulate different wind conditions.
“Wind speed is important, so we focused not only on the spoiler on the car, but also on how the jet and its propeller motors work,” explains Amit, explaining how the tweaks improved the tower’s aerodynamic performance. “The process was a back and forth to find the best shape to increase wind speed and increase surface area.”
Designed as a “mass product”
Air pollution is believed to have killed nearly 1.6 million people in India in 2019 alone, according to a study in the medical journal The Lancet. New Delhi is often shrouded in smog, with vehicle exhaust, crop burning and coal-fired power plants contributing to poor air quality.
Last year, New Delhi was named the city with the highest exposure to fine particulate matter (PM2.5) in the world by the Institute for Health Effects, an American nonprofit that studies the health effects of air pollution. In addition to the direct effects of pollution, heat waves linked to climate change have killed more than 24,000 people in India since 1992, according to a recent University of Cambridge study.
The Guptas said the air pollution they experienced after moving from London to New Delhi prompted them to take action. “Our core business is construction, and we don’t want to get into air purification,” Amit said. “But the air pollution here is unbearable. Very bad.”
It consumes as much electricity as an industrial vacuum cleaner. /Avesh Gaur
Ironically, the tower uses electric fans to draw in air, so emits the very emissions it seeks to reduce, albeit in negligible amounts. Studio Symbiosis aims to reduce the Verto’s environmental impact, with a site-specific energy-efficient design (lower air pollution levels or slowing down when strong winds provide natural airflow) and expensive “smart” fans. Each tower consumes the same amount of electricity as an industrial vacuum cleaner, but has “100 times more” airflow, the architects claim.
Some filters need to be replaced every three to nine months and are recyclable. The tower produces a maximum noise of 75 decibels, about the same level as a typical mixer.
Amit estimated that “around 100” towers would be needed to filter the air in central New Delhi, but a more precise figure would require further research and “full-scale models”. Made of glass fiber reinforced concrete, the tower is easy to assemble and transport for mass deployment.
“You don’t need a lot of molds because you’re iteratively making modules and you can just pack them flat and ship them,” Britta said. “Our goal is to mass-produce this,” Amit added.