The authorities of Xi’an, Shaanxi province, recently invested 900,000 yuan ($160,000) in a removable water cannon tasked to fight the dirty air. But the machine isn’t doing much against the smog.
Xinhua gives a nice explanation of how this technological beauty works and why it’s totally ineffective:
The 10-ton machine can spray water a distance of up to 600 meters and 70 meters high. The water goes up as a fine mist and sticks to dust to form larger particles, which fall to the surface under force of gravity […].
Pan Xiaochuan, an environmental expert at Peking University, said on Sunday that the machine’s role in cleaning air pollution is temporary. Although the machine can reduce its surrounding pollutants within a short period of time after water is sprayed, its effects don’t last long.
The machine is effective in controlling dust from construction sites, but it is useless in combating fine particles like PM2.5 [the main cause of the city’s smog], according to a professor of atmospheric governance from Beijing […].
The major pollution sources in Xi’an are coal combustion, vehicle emissions and industrial releases, not dust, he added.
And Pollution scores another goal!
Xi’an is not the only city that enjoys useless investment! Zhangjiakou, located in Hebei Province, has also employed the machine mounted on the back of a truck, reports People’s daily.
By Aliaume Leroy
[Images via Xinhua and People’s daily]