Drone technology to be used for fine dust up in the air

The Seoul Metropolitan Government is now reviewing to make use of drones (unmanned aerial vehicle) to reduce fine dust, which has increasingly become a serious environmental problem. It has decided that previously-utilized countermeasures such as controlling old diesel cars or absorbing road dust have their limits in resolving the ever-growing problem of fine dust.

“As we need additional measures other than controlling domestic source of fine dust, we are considering different ways to reduce fine dust by utilizing drones,” sources from the city government said on Thursday. According to the Ministry of Environment, more than 80 percent of fine dust from March 17 to 21, when serious level of fine dust covered metropolitan areas was carried from overseas.

There are mainly two ways to utilize drones in removing fine dust. Firstly, tens to hundreds of flying drones equipped with dust removing-filters can inhale fine dust up in the air, which can be dubbed as “a flying air cleaner.” The measure was first introduced in the Science magazine, a renowned U.S. academic journal, last year.

Secondly, flying drones can be used to spray either water or chemical substances. Signing a contract with Aviation Industry Corporation of China, a state-owned aerospace and defense company, in 2014, Beijing began developing such drones. Spraying some 700 kilograms of chemical substances that collect and clot fine dust up in the air, the drone drops clotted dust within the range of 5 kilometers to the ground.

Another type of drone carrying silver iodide that can produce artificial rain is also being developed. The drone with this technology can fly over fine dust-covered area and make artificial rain to wash away floating dust. Gyeonggi Province that similarly suffers from China-triggered fine dust plans to experiment this type of drone technology this year. On the day when fine dust is expected to fly over the West Sea and to reach a serious level, silver iodide-carrying drones can fly over the area and create artificial rain which works as a “shield.”

Seoul is said to consider these types of drone technologies. In fact, making use of drone technology as countermeasures for fine dust has been actively discussed at the government level. In November 2016, the government announced that it would build a moving platform to observe fine dust by 2023 by using drones. This measure can be sufficiently materialized with the current technology as this only requires drones embedded with small sensors to fly up some 2 kilometers in altitude. On the other hand, it has been analyzed that washing away the dust directly up in the air would not be easy in technical perspectives as it requires higher altitude for drones, which has to be equipped with larger-sized devices.

Tae-Ho Hwang taeho@donga.com