smog-tower-a-large-scale-air-purifier-system

In news: Recently, The Supreme Court gave three months’ time to the Centre and the Delhi government for the pilot project of setting up a ‘smog tower to deal with the problem of Air pollution’  at Connaught Place.

Major reasons for the Air Pollution in Delhi-NCR Region:

  • Vehicular pollution due to the high number of internal combustion engine (ICE)-vehicles.
  • The burning of agricultural residues on farms in nearby states.
  • Construction dust from incomplete infrastructure project. 
  • The arrival of dust-laden air from the Middle East and Afghanistan which creates a temperature inversion (cold air on top while hot air is near the ground).
  • Relatively less days of rainfall by the South-West Monsoon. 

Smog Tower

  1. Smog towers are structures designed to work as large-scale air purifiers. 
  2. They are usually fitted with multiple layers of air filters, which clean the air of pollutants as it passes through them. 
  3. China, which has been battling air pollution for a few years, has two smog towers — in its capital Beijing and in a northern city called Xi’an. 
  4. The World Intellectual Property Organisation has notified that A City Cleaner developed by the Kurin System is the world’s largest as well as the strongest air purifier.

The World Intellectual Property Organisation (WIPO):

  • WIPO is the global forum for intellectual property (IP) services, policy, information and cooperation. 
  • It is a self-funding agency of the United Nations with 192 member states.
  • Its mission is to lead the development of a balanced and effective international IP system that enables innovation and creativity for the benefit of all. 

Intellectual property (IP):

  • IP refers to creations of the mind, such as inventions; literary and artistic works; designs; and symbols, names and images used in commerce.
  • Types of intellectual property: Copyrights, Patients, Trademarks, Industrial Designs, Geographical Indications and Trade Secrets. 

Various technologies which could be used to deal with air pollution.

  1. A City Cleaner by the Kurin System.
  2. Hooded stoves with chimneys vent pollutants outdoors.
  3. Passive solar heating and cooling techniques.
  4. WAYU (Wind Augmentation PurifYing Unit):
  1. Air pollution control device WAYU (Wind Augmentation PurifYing Unit) for traffic junctions at ITO intersection.
  2. WAYU is developed by Council of Scientific and Industrial Research – National Environmental Engineering Research Institute (CSIR-NEERI) as a part of Technology Development Project being funded by Department of Science and Technology.
  3. It has the capacity to purify air in an area of 500-meter square. 

Recommendations of the high-level committee to examine the feasibility of using technology like smog towers and smog guns to combat air pollution.

  1. Painting roads with photocatalytic coating to clean air: 
    1. Photocatalytic paints contain titanium dioxide [TiO2] which acts as a catalyst when exposed to UV rays and removes atmospheric pollutants. 
    2. The catalyst converts the pollutants into other species. 
    3. Issues: The nano materials may result in production of other undesirable species such as nitrous acid and formaldehyde which will have adverse health impacts. 
  2. Using anti-smog guns at construction sites to reduce dust pollution. 
  1. Anti-smog gun is a device that sprays nebulised water droplets into the air through high pressure propellers, which help particles to settle down.
  2. It may be effective in controlling localised dust during the period of application and more suitable to high dust emission zones such as large construction sites
  1. Setting up of a 20 metre-high ‘smog tower’ with air purifiers.
  1. 65% reduction in pollution can be achieved on an average up to 700 metres from the tower. 
  2. It is expected to influence air quality of more than 1 km in the downwind direction, according to officials.
  3. Issues: Smog towers, as per the current knowledge and experience, may not provide a viable solution to improve air quality on a large scale. 
  1. Using wireless sensors Network (WSN) for monitoring pollution. 
  1. WSN may be used as an indicative monitoring tool for a few activities like mining, large construction sites, to supplement air quality data and report to regulator for conducting further investigation.
  1. Oxy furnace
  1. Oxy furnace uses only oxygen as fuel instead of atmospheric air (which contains nitrogen), thus reducing the production of NOx by about 90% in industries.
  2. Issues: NOx is mostly released in urban centres from vehicles and not industries.
  1. LiDAR or Light Detection and Ranging:
  1. It is a high-end application of LASER-based technology for monitoring pollution. 
  2. This technology may be adopted for vertical monitoring at a few places to track transport of pollutants at higher altitudes.