An air purifier you can make at home

Air pollution is shortening lives by 11.9 years in the National Capital Territory of Delhi as per the Air Quality Life Index report. This shocking fact indicates that air purification systems are the need of the residents of densely populated and highly polluted cities. I and a few friends were very concerned about this issue and decided to try solving it. And so, as our innovation for the CSET Challenge, my friends and I designed a solution to indoor air pollution.

Here is a brief on our innovation, Uyirvayu, which translates to ‘Life-giving air.

Uyirvayu is an eco-friendly air purifier powered by solar energy. It is based on the scientific principles of adsorption, uses locally available materials (comparative to Delhi and Coimbatore, our present focus cities) and can be made in homes. 

Uyirvayu’s filtering system mainly consists of activated carbon, a filtering medium obtained from old coconut shells, which are abundant in India. It uses a suction fan to gather outside air for filtration, powered by the solar panel.  After this, the purified air moves towards the open side of the frame. As air flows into the system contaminants like volatile organic compounds (VOCs), gases, and odors are adsorbed onto the carbon's surface. The activated carbon is packed in a wire gauze mesh, which is porous and light. It has a biodegradable bamboo exterior. 

We tested the prototype at a lab with a simulation of severe indoor air pollution. CO2 levels dropped from 60000 ppm to 800 ppm, the normal atmospheric level, within seconds of implementation. Now we’re excited about scaling it to an actual product that could benefit millions of people. Our next steps include:

• Integrating a screen that displays live air quality data.

• An energy storage system that can allow us to use the purifier at night as well.

• Developing dynamical models to simulate adsorption and airflow within the purifier.

• Researching optimal regeneration conditions for the activated carbon.

• Hybridizing the system with technologies like electrostatic precipitation, which can attract more contaminants to the filter.

• Implementing a feedback loop that uses air quality sensor data to adjust fan operation and even trigger regeneration cycles when adsorption capacity is nearing saturation.

• Including more eco-friendly filtration layers.

This is just one small example of three 16-year-olds working together to solve a problem. We all have so much potential. There’s no better time for each of us to step up and be the change we want to see in the world.

Team members:

Divyasree Gorantla; bevisioneers: Mercedes-Benz Fellow

Shreya Kaushik; Indian Eco-gen ambassador

Deeksha Ravi; Indian Eco-gen ambassador

References:

Li, L., Sun, Z., Li, H., & Keener, T. C. (2012). Effects of activated carbon surface properties on the adsorption of volatile organic compounds. Journal of the Air & Waste Management Association, 62(10), 1196–1202. https://doi.org/10.1080/10962247.2012.700633

University of Chicago. (2023, August). Air Quality Life Index.. https://aqli.epic.uchicago.edu/wp-content/uploads/2023/08/India-FactSheet-2023_Final.pdf