10th International Aerosol Conference September 2 - September 7, 2018 America's Center Convention Complex St. Louis, Missouri, USA
Abstract View
On-Line Measurements of Selenium Emissions from an Operating Coal Fired Power Plant
Edward Fortner, Joseph Roscioli, Jordan Krechmer, Manjula Canagaratna, Scott Herndon, JOHN JAYNE, Aerodyne Research, Inc.
Abstract Number: 903 Working Group: Combustion
Abstract Coal fired power plants are a significant emission source of criteria gas pollutants as well as trace elements. Volatile toxic elements pose special concerns since they may not be efficiently removed by existing gas phase control measures in modern power plants and can therefore pass through the different process streams and be emitted into the environment. While some elements such as sulfur and mercury have regulatory emission controls imposed others do not. One such element is selenium which is believed to exist mostly in the oxidized form. Selenium dioxide has received special attention since it has volatility characteristics that allow it to partition between the gas and condensed phases at typical flue gas exhaust temperatures. The relatively high volatility has made it difficult to quantify the fate of selenium using standard analytical filter based collection methods. Prior measurements of selenium in the flue gas have shown wide variability in material balance closures indicating an incomplete understanding of the behavior of selenium in the process stream. Here we present results from a field measurement project that demonstrates the use of advanced technology instrumentation for the real-time, on-line detection of trace pollutants from an operating power plant. Both mass spectrometric and infra-red spectroscopic instrument systems were used to measure the concentrations of selenium dioxide in the flue gas and to estimate gas-particle partitioning, emission indices and removal efficiencies. To our knowledge this was the first time such measurements have been made at an operating power plant with these instrument technologies and demonstrates their applicability for use in collecting chemically speciated data from power plant streams in real-time.