Air Pollution in India is a serious issue with the major sources being fuelwood and biomass burning, fuel adulteration, vehicle emission and traffic congestion. Department of Science & Technology (DST) initiated a solution oriented R&D activity for mitigation of Air Pollution. The programme focusesto identify the technologies that can provide viable deployable solution to mitigate the air pollution and to establish technical resource unit.

Programmes

1. Traffic Junction Air Pollution Abatement Plan

DST with CSIR-NEERI has developed Wind Augmentation and Air Purifying Unit (WAYU) devices that can be positioned in an industrial complex, residential complexes, and schools in the vicinity of traffic road intersection/divider to tackle air pollution.  This device works basically on two principles i.e.  Wind generation for dilution of air pollutants and active pollutants removal. The device would use low-speed wind generators, appropriate size filters for long operation cycle with reasonable efficiency. It also will have an oxidizer unit for removal of Carbon-monoxide and Hydrocarbons including VOCs.

WAYU can reduce PM10, PM 2.5, Carbon monoxide (CO), volatile organic compounds (VOCs), hydrocarbon (HC) emitted in the atmosphere. This device works basically on two principles mainly wind generation for dilution of air pollutants and active pollutants removal. The device consumes a half unit of electricity each day for running for 10 hours each day. The cost of the device is Rs.60000 per device. Maintenance cost is Rs.1500 per month.

2. Landfill Fire Control Mechanism through Integrated Approach

Landfills are the ultimate disposal option adopted in India. In India, most of the landfills are non-scientific and non-engineered which do not have any leachate and gas collection systems. Open burning of waste and landfill fires are among the largest sources of air pollution in Indian cities and towns. Landfill fires emit nearly 22000 tons per year of pollutants into the air in the city of Mumbai alone. These pollutants include Carbon Monoxide (CO), Hydrocarbons (HC), Particulate Matter (PM), Nitrogen Oxides (NOx) and Sulfur Dioxide (SO₂) plus an estimated 10000 TEQ grams of  dioxins/ furans. In view of these facts, this project will understand the cause, source, type and effects of fire in a dumpsite/landfill and to develop an integrated approach for its proper control.

3. Suddha Vaayu: An Electrical Chamber for Detection and Mitigation of Air Pollution

The proposed project is divided into two phases. In the first phase, the prototype of the electrical mitigation chamber will be designed. The proposed prototype consists of three steps of the purification process. In the first step, large particles will be removed using metal mesh or other possible best means. A 5 µm pore diameter fiber filter will be used to remove PM 10 in the second stage. In the third stage, a paper made rundfilter of 2 µm pore diameter will remove PM 2.5. The walls of the mitigation device are coated with silica gel to remove the moisture content from the air. The mitigation device has the capability to run with both external power and energy generated with the solar panels installed on the device. In general 250 watts solar panel with 24 v input is sufficient to power this system. SuddhaVaayu: electrical chamber is expected to have an efficiency of 88-90% to remove PM 2.5 and PM10.

Based on the results from the first phase, multiple pilot chambers will be fabricated and set up at selected locations in Delhi in the second phase. The real-time efficiency of the pilot units will be tested using the integrated air quality sensor platform made and validated as a deliverable of this project.

4. Collecting Particulate Matter in Air Using Filters Placed on the Top of a Moving Car

The proposed project is divided into two phases. In the first phase, the performance of the existing purifier designed by Shudh Vayu LLC will be evaluated using CFD analysis for different scenarios pertaining to operating conditions of the car, meteorology, make and model of the car etc. The prototype consists of three stages of purification process. In the first step large particles will be removed using metal mesh. The second and third stages have foam and HEPA filters, respectively.

The main advantage of this purification system is its principle of pressure difference created due to air flow generated by a moving vehicle. However, as a part of project deliverables, relevant on field tests on the efficiency of the existing filter and the modified filter based on the CFD simulations will be carried out in this project. Additionally, a sensor fusion system which can be mounted on the top of the car will be designed and fabricated which will aid in measuring the real time concentrations of air pollutants. Such a sensor fusion system will aid in real-time air quality mapping of a city. As HEPA filters used in the current design are not washable and re-generatable, large scale usage of the purifier might end up creating solid waste management issues. Thus one of the objectives of this project is developing an affordable and washable air filter, which is of good efficiency.

5. Indigenous Photonic System for Real Time Remote Monitoring of Air Quality

The aim of this project is to test proof of concept of the novel indigenous photonic system for real time remote monitoring of air quality. The project will develop the field deployable novel indigenous air quality monitoring photonic system and evaluate the same in laboratory trials with gold standards. It will also conduct field trials at designated site of existing CPCB air quality monitoring station for inter-comparisons purposes.

6. Mitigation of Air Pollution: Micro-to-Macro Scale Study of Particle Capture by Liquid Droplets

Air pollution comprises of smoke, dust and haze which can be collectively named as aerosols which defines suspension of small particles in air. The sources of particles, aerosol and species that are the constituents of polluted air are manifold, such as, vehicle tail-pipe emissions, road dust kicked up by vehicles, construction sites, dumping of sand and cement, road sweeping, open ovens and furnaces operated by local industries, garbage fires, biomass/ wood burning cook-stoves, brick kilns, factory exhausts, stubble burning, and dust entrained by winds, amongst others. Wind and change in temperature affect the transport of pollutants in air. A mixture of these is distributed in the air people breathe which is known to lead to adverse health effects.

The fundamental aim of the project is to study of particulate matter (PM) capture efficiency by single droplet using two techniques of electrostatic charging of droplet and/or aerosol and addition of additives based on chemical characteristics of the aerosols.