Flue-gas desulphurisation (FGD)

The Government of India has significantly eased sulphur emission regulations for coal-fired power plants, exempting 79% of them from installing flue-gas desulphurisation (FGD) systems. This change, outlined in a government order issued on July 11, targets plants located beyond 10 km from designated pollution hotspots.

Revised Compliance Categories and Deadlines:

The July 11 notification, citing the environment ministry, outlines new compliance categories and timelines for sulphur dioxide (SO2) emission standards:

• Category A Plants (10% of total):
  • These are plants located within a 10-km radius of the National Capital Region (NCR) or cities with a population exceeding one million.
  • They are now required to install desulphurisation equipment by December 2027, an extension from the previous December 2024 deadline.
• Category B Plants (11% of total):
  • These plants are situated within a 10-km radius of critically polluted areas or non-attainment cities.
  • Compliance for these plants will now be assessed on a case-by-case basis, rather than adhering to the earlier December 2025 deadline.
• Category C Plants (79% of total):
  • This category includes all other plants not falling under Category A or B.
  • They have been completely exempted from the sulphur dioxide norms, provided they meet the prescribed stack height criteria by December 31, 2029. Previously, these plants were required to comply by December 2026.

Background on SO2 Emissions:

• Sulphur dioxide emission standards for coal and lignite-based thermal power plants in India were initially published in 2015, with timelines that were subsequently amended.
• The largest source of SO2 in the atmosphere is the burning of fossil fuels by power plants and other industrial facilities.
• Smaller sources include industrial processes (like metal extraction from ore), natural sources (such as volcanoes), and vehicles/heavy equipment burning high-sulfur fuel.

(Sources: BL & Others)