15 Oct Centre to help set up paddy straw pellet units to curb stubble burning
Impact of Stubble Burning on Delhi Air Pollution
The topic is based on Delhi Air Pollution. The article tells how the Center helps to set up paddy straw pellet units to curb stubble burning and reduce the pollution of Delhi.
The Ministry of Environment has announced financial aid to industries to establish paddy straw pelletization and torrefaction plants. The Government has set aside Rs.50 crore for it. With increasing cases of stubble burning being witnessed in Punjab and Haryana and the onset of the winter season, the scheme is aimed to lower the rising air pollution in Delhi while at the same time converting “waste to wealth” and ensuring a “Clean India”
DELHI AIR POLLUTION AND ISSUE OF STUBBLE BURNING
- Delhi has been consistently facing the problem of air pollution for about two decades now. Last week, the Air Quality Index in Delhi dropped to 211 which is considered “Poor” according to the National Air Quality Index.
- A recent report released by US-based Health Effects Institute Air Quality carrying a global analysis of air quality of different cities found Delhi’s PM 2.5 levels to be the worst in the world.
- Scientists have also warned of a possible rise of 30 to 70 percent in pollution levels in Delhi in the upcoming days with the new crop season quickly approaching which would result in massive stubble burning by farmers.
REASONS FOR AIR POLLUTION IN DELHI:
- Stubble burning is one of the driving reasons for the issue of air pollution in Delhi every year. Farmers have to clear the fields of the residue of the rice harvest in October to prepare the fields for sowing wheat.
- Thus, farmers prefer to burn the rice stubble since it is a quick and cheap method to get rid of the stubble and prepare the field for the rabi season.
- This practice had been ongoing since the 1980s but it became problematic after the passage of the Punjab Preservation of Subsoil Water Act, 2009 (PPSW)
- Before the act, the farmers sowed and transplanted paddy between April and May but the amount of water required for irrigation in peak summers depleted groundwater.
- Thus, to preserve groundwater and ensure the major water requirement of irrigation is met through the monsoon, the Punjab government passed the act barring the sowing of paddy before 15th May and transplanting of paddy before 15th June, respectively.
- This move left farmers with little time between the harvesting of paddy and preparing the field for sowing wheat. Therefore, farmers were left with no choice but to burn the stubble since it saved time.
- The stubble period now coincides with the onset of winters in northern India which creates such geographical conditions that the burnt particles and smog settle in the air causing air pollution levels to rise.
- As the monsoon withdraws by October from Northwest India, the predominant direction of winds also changes to northwesterly. This change in the direction of wind brings pollutants from Punjab and Haryana to Delhi
- With the Himalayas acting as a huge barrier to the north, the smog from stubble burning has no way to escape and accumulate in Northern India, especially in Delhi.
- Temperature inversion also makes the matter worse. Hot air generally rises above and escapes from the near ground but due to cool winter air, the smog is unable to rise and remains trapped within the plains.
Thermal Power Plants
- Emissions from thermal power plants cause air pollution in the national capital. These pollutants travel long distances and get converted into secondary particles due to photochemical, oxidation, and adsorption reactions.
- These secondary particles remain in the atmosphere for a long time and move to longer distances.
- A recent report jointly published by IIT Kanpur, the Delhi Pollution Control Committee, and the Department of Environment, NCT Delhi (2016) reveals that Road Dust is the single largest contributor to Delhi’s air pollution. It accounts for about 56 percent of PM10 and about 38 percent of PM2.5 particles.
- Firecrackers during Diwali add to the above pollution sources. The emissions from crackers stay in the air due to temperature inversion and particles accumulate to create smog in the air. A report by the Centre for Science and Environment found that the concentration of PM2.5 increased during Diwali in 2018, 2019, and 2020 in Delhi.
PADDY STRAW PELLETISATION AND TORREFACTION PLANTS
- Pelletisation refers to converting paddy straw into pellets which can be utilized in thermal power plants and industries as fuel.
- Torrefaction is a thermal process used to produce high-grade solid biofuels from various streams of woody biomass or agro residues. It enhances the physical and chemical properties of biomass.
- This will ensure ex-situ management of crop residue by using it as biofuel.
- Farmers will be incentivized not to burn stubble and gain some additional income by selling the stubble to industries manufacturing pellets
- The paddy straws can be mixed with coal after it is converted to pellets or torrefied. Hence, carbon emissions are reduced.
- While paddy straw pelletization and torrefaction are significant steps to incentivize farmers not to burn stubble, other steps need to be combined with this move:
- Use of agricultural machines like:
- Happy Seeder(used for sowing of the crop in standing stubble)
- Rotavator (used for land preparation and incorporation of crop stubble in the soil)
- ZBNF (directly sowing of seeds in the previous crop stubble)
- Baler (used for collection of straw and making bales of paddy stubble)
- Paddy Straw Chopper (cutting of paddy stubble for easily mixing with the soil)
- Reaper Binder (used for harvesting paddy stubble and making it into bundles)
Promoting the use of bio-decomposer
- Bio-decomposer is a mix of seven fungi that produce enzymes to digest cellulose, lignin, and pectin in paddy straw. A liquid formulation is made using the decomposer and then sprayed on the fields with crop stubble to ensure speedy bio-decomposition of the stubble. The Delhi Government has been promoting its use to help decompose stubble into manure.
Controlling Vehicular Pollution
- This can be done by imposing a ceiling on the number of vehicles a household can own. The use of CNG and e-vehicles can be promoted to phase out petrol and diesel cars in the future. Further, public transport needs to be strengthened and its uses encouraged