At a park in one of the world’s most polluted cities, a sleek filtration “tower” has been quietly purifying the surrounding air since last summer. Dubbed Verto, the 5.5-meter-tall device reduces levels of nitrogen dioxide and dangerous fine particles in New Delhi’s Sunder Nursery by filtering 600,000 cubic meters of air a day — which is equivalent to the volume of 273 hot air balloons.

Now, having collected data from their prototype, the architects behind the invention believe their project can be scaled up to clean big public spaces, neighborhoods and even entire cities.

Designed by architecture firm Studio Symbiosis, which has offices in India and Germany, the towers contain five air filtration “cubes” stacked inside a geometric shell. The firm’s husband-and-wife co-founders, Amit and Britta Knobel Gupta, say their fan-powered devices can clean air within a radius of 200 to 500 meters in enclosed spaces, though outdoors this distance would be 100 to 350 meters, depending on wind speed and how open the surroundings are.

“Now that (findings from the prototype) are what we expected, we will start speaking to the government authorities about further installation,” Amit saidi, revealing that the firm has also spoken to potential buyers in countries from Uzbekistan to France and New Zealand. Studio Symbiosis said that a construction company in the U.S. is considering ordering around 40 of the towers to tackle dust and fine debris at building sites.

“I think (they could also be installed) in public parks and public plazas, where people spend quality outdoor time,” Britta said, adding that installing the towers in spots where homeless people sleep might also be “very beneficial.”

Deriving its name from the Latin word “vertente,” or “to turn,” Verto’s twisting form was designed to push as much air as possible across the device’s surface, where it is sucked into filters and expelled. Using filters from German firm Mann+Hummel, the Studio Symbiosis architects focused on creating the most efficient shape for the towers, with digital models simulating different wind conditions.

“It’s all about wind velocity, so we looked at jets — and how their propeller engines work — as well as car spoilers,” Amit said, explaining how small adjustments made the towers more aerodynamic. “It was a back-and-forth process, in terms of trying to get the optimum shape that would increase the wind speed and the surface area.”

In 2019 alone, air pollution is thought to have caused nearly 1.6 million deaths in India, according to a study in medical journal The Lancet. New Delhi is regularly shrouded in smog, with vehicle emissions, crop-burning and coal-fired power plants all contributing to the city’s declining air quality.

The U.S.-based Health Effects Institute last year named India’s capital as the city with the highest exposure to fine particulate matter, or PM2.5, in the world.

Ironically, by using electric fans to suck in air, the towers are contributing — albeit negligibly — to the very emissions they are trying to mitigate. To reduce Verto’s environmental impact, Studio Symbiosis installed energy-efficient “smart” fans that vary according to local conditions (slowing down when pollution is low, or when strong winds provide natural airflow). The architects claim that each tower consumes power at the same rate as an industrial vacuum cleaner “but with 100 times the airflow.”

The filters, which need to be changed every three to nine months, are partly recyclable, they added.

Words to Learn

相关词汇

【速度】

sùdù

velocity

the speed of something in a given direction

【减轻】

jiǎnqīng

mitigate

make less severe, serious, or painful

新德里是当今世界上污染最严重的城市之一，去年夏天，这里的一个公园安装了一个光滑的过滤塔，在悄悄地净化周围的空气。桑德苗圃里这个被称为Verto的装置高5.5米，每天过滤60万立方米的空气 —— 相当于273个热气球的体积 —— 有效降低了空气中二氧化氮和其它有害颗粒的水平。

在收集了过滤塔的数据后，建筑师们相信这个项目可以推广到大型公共场所、社区甚至整个城市。

共生工作室设计了这个项目，这家建筑事务所在印度和德国设有办事处。过滤塔包含五个空气过滤模块，堆叠在一个几何外壳内。该公司的联合创始人是一对夫妻。阿米特•古普塔和布丽塔•诺贝尔•古普塔说，他们的风扇设备可以在封闭空间内200至500米的半径范围内净化空气，在户外这个距离是100至350米，取决于风速和周围环境的通透程度。

阿米特说：“既然过滤塔符合预期，我们将与政府当局讨论进一步推广的事宜。”他透露，该公司与从乌兹别克斯坦到法国和新西兰等国的潜在买家都有接洽。共生工作室说，美国一家建筑公司正考虑订购大约40个过滤塔来净化建筑工地的空气中的灰尘和颗粒。

布丽塔说：“我认为（它们也可以安装）在公园和广场等户外休闲场所。”他补充说，在无家可归者睡觉的地方安装过滤塔也是“非常有益的”。

Verto的名字来源于拉丁语 “vertente”，即“曲面”，其扭曲的形状旨在让尽可能多的空气通过设备的表面，将其吸进过滤器净化后排出。采用德国曼•胡默尔公司的过滤器，共生工作室的建筑师们为过滤塔设计最有效的形状，用数字模型模拟不同的风况。

“问题在于风速，所以我们研究了喷气机，以及它们的螺旋桨发动机是如何工作的，还有汽车的扰流板，”阿米特说。微小的调整能使过滤塔更符合空气动力学。他说：“为提高风速、增加表面积而寻找最佳形状是一个反复试错的过程。”

根据医学杂志《柳叶刀》的一项研究，仅2019年，空气污染在印度造成近160万人死亡。新德里常年被烟雾笼罩，汽车尾气、农作物燃烧和燃煤电厂都导致了该城市空气质量下降。总部设在美国的健康影响研究所去年将印度首都命名为世界上空气中细颗粒物（PM2.5）含量最高的城市。

略有讽刺意味的是，使用电扇来吸入空气，这些过滤塔本身也造成了污染 —— 尽管可以忽略不计。为了减少Verto对环境的影响，共生工作室安装了节能的智能风扇，根据外界条件作出调整（污染较少或有强风时，风扇会放慢速度）。建筑师声称，每座塔的耗电量与工业吸尘器相同，“但气流是其100倍”。他们补充说，过滤器每三到九个月需要更换一次，部分是可以回收再利用的。(SD-Agencies)