Effective Reduction of Condensable Particulate Matter from Coal Combustion Flue Gas (Student Poster #22)

Abstract Description: Particulate matter (PM) emitted from coal-fired power plants can be broadly categorized into two types: filterable particulate matter (FPM) and condensable particulate matter (CPM). While FPM exists as solid or liquid particles in the flue gas and can be effectively removed using dust collection devices such as electrostatic precipitators or fabric filters, CPM presents a more challenging issue. Unlike FPM, CPM exists in a gaseous state within the flue gas and only forms particulate matter when the gas cools and condenses. This makes CPM more difficult to capture and control, as it often bypasses traditional particulate removal systems.
CPM is primarily generated during the coal combustion process, where high temperatures cause certain chemical components in coal to vaporize. As the flue gas cools during its journey through the system, these vaporized components condense and form fine particles through cooling and dilution mechanisms. This process not only complicates the removal of CPM but also raises concerns about its environmental and health impacts, as these fine particles can contribute to air pollution and pose risks to human health when emitted into the atmosphere.
To address the challenges associated with CPM, we explored a novel approach involving the injection of a specific substance anticipated to effectively reduce CPM formation. This method leverages the physical and chemical processes underlying CPM generation, aiming to inhibit its formation or enhance its removal before it exits the system. To evaluate the effectiveness of this approach, we conducted a series of experiments using a laboratory-scale combustion furnace designed to simulate the conditions of a coal-fired power plant. The experimental setup included a filter system that mimicked the operation of a fabric filter, allowing us to assess the impact of the injected substance on CPM reduction under controlled conditions.
In our study, various experimental conditions were tested to comprehensively evaluate the reduction effect of the injected substance on CPM. The CPM was recovered and quantified following the guidelines of the Environmental Protection Agency (EPA) Method 202, a standardized procedure for measuring condensable particulate emissions. Additionally, the inorganic components of the recovered CPM were analyzed using ion chromatography to better understand the chemical composition and assess any changes induced by the injected substance.

Keywords: Condensable particulate matter