Assessment of national emissions of air pollutants and climate forcers from thermal power plants and industrial activities in Vietnam

This study developed a comprehensive emission inventory (EI) for thermal power plants (TPPs) and industrial activities in Vietnam for 2010. A combined top-down and bottom-up EI was conducted using fossil fuel consumption data of TPPs and industrial activities collected at the provincial level. Emission factors (EFs) were selected from literature considering the relevancy to the country emission sources. The best emission estimates, collectively from TPPs and industry activities, in Gg, was: 361 CO, 320 NOx, 529 SO2, 52 NMVOC, 13 NH3, 266 PM10, 79 PM2.5, 2.6 BC, 4.7 OC and 105,856 CO2, which were mainly contributed by the industrial activities. The range between low and high emission estimates were determined for each species and the largest ranges were found for BC and SO2. Spatial emission distributions showed higher intensities over major economic zones of the country. The lowest monthly emissions were seen in February coinciding with the Lunar New Year holiday which were followed by the peaks in March when the economic activities resumed. The net GWP of the emissions in 20-yr CO2 equivalent was 59.7 Tg with CO2 emissions having the largest share (87%) followed by BC (6%), whereas sulfates were the main cooling agent. Fuel switching to natural gas would significantly reduce emissions from TPPs while better combustion and emission control technologies applied in small and medium industries would reduce emissions of PM species including BC. The emission database developed in this study can be used in dispersion modeling for air quality management studies in Vietnam.