Greenhouse Gas Emissions in Wastewater Treatment Plants Linked to Significant Carbon Footprint

Strategic Insights -

Recent research at Rajamangala University of Technology Rattanakosin has shed light on the significant contribution of greenhouse gas emissions in wastewater treatment plants (WWTPs) to the environment, particularly in the areas of Naklua, Pattaya City, and Jomtien. The study, conducted from 2021 to 2023, analyzed the carbon footprint of two WWTPs in Pattaya City and found that the total carbon footprint ranged between 5,610.61-6,020.18 tons of CO2 equivalent per year. The main sources of emissions were identified as the wastewater collection system, activated sludge process, and electricity consumption, accounting for 34.47-44.61%, 43.02-45.74%, and 30.02-39.48% of the total emissions, respectively.

Key Takeaways:

  • The total carbon footprint from the WWTPs in Pattaya City had the potential to contribute 5,610.61-6,020.18 tons of CO2 equivalent per year.
  • Carbon intensity ranged between 0.45-0.47 kg CO2 equivalent per cubic meter of treated wastewater.
  • The main sources of emissions were the wastewater collection system, activated sludge process, and electricity consumption, accounting for 34.47-44.61%, 43.02-45.74%, and 30.02-39.48% of the total emissions, respectively.
  • Installing solar cells on the office building roof could generate 156,780 kWh annually, resulting in a reduction of 108.70 tons of CO2 equivalent per year, and a savings of 35,658.52 USD.
  • Installing solar cells in the plant could generate 823,680 kWh annually, leading to a reduction in GHG emissions of 571.06 tons of CO2 equivalent per year, or 12.50%, and a savings of 187,304.58 USD.
  • Installing a WWTP at station PS12 with a capacity of 60,874.65 cubic meters per day could reduce the GHG footprint from the wastewater collection system by 1,219.44 tons of CO2 equivalent per year, or 36.41%, and result in a savings of 239,091.57 USD.
  • The research suggests three options for GHG reduction and recommends exploring resource recovery, nutrient recycling, water reuse, and energy production on-site with combined heat and power (CHP) from biogas to reach carbon neutrality and energy sustainability.

Statistics:

  • Total carbon footprint: 5,610.61-6,020.18 tons of CO2 equivalent per year
  • Carbon intensity: 0.45-0.47 kg CO2 equivalent per cubic meter of treated wastewater
  • Emissions from wastewater collection system: 34.47-44.61% of total emissions
  • Emissions from activated sludge process: 43.02-45.74% of total emissions
  • Emissions from electricity consumption: 30.02-39.48% of total emissions
  • Reduction in GHG emissions by installing solar cells on the office building roof: 108.70 tons of CO2 equivalent per year
  • Savings from installing solar cells on the office building roof: 35,658.52 USD
  • Reduction in GHG emissions by installing solar cells in the plant: 571.06 tons of CO2 equivalent per year
  • Savings from installing solar cells in the plant: 187,304.58 USD

Sources:

  • A Comprehensive Carbon Footprint Analysis and Emission Reduction in Wastewater Treatment Plants: A Case Study in Pattaya City. Environment and Natural Resources Journal, 2025,23(4):289-298.
  • https://www.tci-thaijo.org/index.php/ennrj/index