Devices to Control Air Pollution | 14 Nov 2019
Why in News
The air purifiers installed on the roads and on top of the buses have failed to combat air pollution in Delhi NCR.
- The air purifying devices include WAYU (Wind Augmentation PurifYing Unit) and High-Efficiency Particulate Arrestance (HEPA) filters.
WAYU (Wind Augmentation PurifYing Unit)
- It is developed to address air pollution at traffic intersections and dense traffic zones.
- It has been indigenously developed by the Council of Scientific and Industrial Research - National Environmental Engineering Research Institute (CSIR-NEERI).
- The device has the capacity to purify the air in an area of the 500-meter square. It is energy efficient and has a low maintenance cost.
- The device works on two principles :
- Wind generation for dilution of air pollutants: It comprises a fan that sucks in air and removes dust and particulate matter.
- Active Pollutant removal: The carbon monoxide and hydrocarbons are oxidized into less harmful carbon dioxide using activated carbon coated with titanium dioxide.
High-Efficiency Particulate Arrestance (HEPA) filters
- These filters are able to trap 99.97 % of particles that are 0.3 microns.
- It traps air contaminants in a complex web of fibers.