Direct greenhouse gases from domestic wastewater treatment plant in Bandung Regency, West Java, Indonesia

Abstract

Wastewater treatment contributes direct greenhouse gas (GHG) emissions in the atmosphere. The study aims to estimate the amount of methane (CH4) and carbon dioxide (CO2) emitted from domestic wastewater treatment plants (WWTP) in Bandung Regency throughout the years 2019-2022. Wastewater treatment processes in the WWTP consist of anaerobic, facultative, and maturation ponds. Data series of water quality from each process were collected on a monthly basis from years 2019 to 2022 to estimate direct emissions. Emission factors used in this study were derived from IPCC Guidelines and using the Tier 1 method. The highest GHG emission from WWTP Bojongsoang was about 513.44 tonCO2e in December 2021. The monthly average CO2e emissions from year to year increased about 40.12%. The average GHG emission from WWTP Bojongsoang from the year 2019 to 2022 respectively was about 81.33 tonCO2e/month, 135.21 tonCO2e/month, 229.26 tonCO2e/month, and 193.89 tonCO2e/month. Overall, the percentage of CO2e emission from anaerobic pond was about 93.57%, from facultative pond was about 4.86%, and from maturation pond was about 1.57%. The highest CO2e emissions occurred in the anaerobic pond along with the highest COD reduction also took place in the anaerobic pond.