Sulfur Dioxide Emission Norms

• 31 Jul 2023

Source: PIB

Why in News?

Recently, the Ministry of Power has informed Lok Sabha that, for compliance with Sulphur dioxide (SO₂) emission norms, Thermal Power Plants are installing Flue Gas Desulphurisation (FGD) equipment.

• The Ministry in September 2022 had extended the deadline for Coal-Fired power plants to install FGD to cut sulphur emissions by two years.

What is the Categorisation of Power Plants for Installing FGD?

Category	Location/Area	Timelines for compliance
Category A	Within 10 km radius of National Capital Region (NCR) or cities having million plus population (as per 2011 census of India)	Upto 31st December 2024
Category B	Within 10 km radius of Critically Polluted Areas or Non-attainment cities (as defined by CPCB)	Upto 31st December 2025
Category C	Other than those included in category A and B	Upto 31st December 2026

What is Flue Gas Desulfurization (FGD)?

• About:
  • FGD is the process of removing sulfur compounds from the exhaust emissions of fossil-fueled power stations.
  • This is done through the addition of absorbents, which can remove up to 95% of the sulphur dioxide from the flue gas.
  • Flue gas is the material emitted when fossil fuels such as coal, oil, natural gas, or wood are burned for heat or power.
• Need for FGD in India:
  • Indian cities have some of the world’s most polluted air. India currently emits almost twice the amount of SO₂ than the next highest country, Russia.
  • Thermal utilities, which produce 75% of the country’s power, account for some 80% of industrial emissions of sulphur and nitrous oxides, which cause Lung Diseases, acid rain and smog.
  • Every single day delay in implementation of prescribed norms and not installing the FGD system is causing huge health and economic damage to our society.
    • The high levels of damaging SO2 pollution in India are avoidable much sooner as FGD systems have proved successful in reducing emission levels in China, which was responsible for the highest level of SO₂ Pollution in 2005.

What is Sulfur Dioxide Pollution?

• Source:
  • The largest source of SO₂ in the atmosphere is the burning of fossil fuels by power plants and other industrial facilities.
  • Smaller sources of SO₂ emissions include industrial processes such as extracting metal from ore, natural sources such as volcanoes, and locomotives, ships and other vehicles.
• Impact:
  • Short-term exposures to SO₂ can harm the human respiratory system and make breathing difficult. People with asthma, particularly children, are sensitive to these effects of SO₂.
  • The WHO has estimated that it causes 4.2 million deaths globally per year.
  • SO₂ emissions that lead to high concentrations of SO₂ in the air generally also lead to the formation of other sulfur oxides (SOx).
  • SOx can react with other compounds in the atmosphere to form small particles. These particles contribute to Particulate Matter (PM) pollution.