Effective Control of Condensable Particulate Matter from Coal-Fired Flue Gas Using Alkaline Sorbent and Activated Carbon

Particulate matter (PM), particularly PM2.5, has become a significant air quality concern due to its adverse health effects. Among the sources of PM, coal-fired power plants contribute substantially through both filterable PM (FPM) and condensable PM (CPM). While air pollution control devices (APCDs) effectively remove FPM, CPM remains a dominant fraction in treated flue gas. This study investigates CPM behavior and control mechanisms using a laboratory-scale coal combustion system designed to simulate coal-fired power plant operations. CPM emissions were analyzed under varying temperatures, filtration conditions, and sorbent applications to determine their influence on CPM concentration and composition. Results indicate that CPM concentrations decrease with temperature, primarily due to heterogeneous reactions converting precursor gases into particulate form. Filtration reduced CPM inorganic components but had a minimal impact on organic CPM. The application of alkaline sorbentsNaHCO₃ and Ca-(OH)₂demonstrated effective CPM reduction. Activated carbon injection selectively reduced organic CPM, highlighting its role in adsorbing volatile organic compounds. These findings emphasize the importance of temperature control, filtration, and chemical sorbents in effectively mitigating CPM emissions from coal-fired power plants.