Laser spectroscopic investigation of formation and conversion of isocyanic acid during the aftertreatment of combustion exhaust gases
Final Report Abstract
The determination of absolute HNCO mole fractions in high temperature processes requires more advanced diagnostics than can be realized with conventional FTIR systems. Therefore, this project proposed the use of laser absorption spectroscopy based on TDLAS as a future tool for HNCO diagnostics in technical systems and worked in the fundamentals of molecular spectroscopy to support future application of HNCO-TDLAS. A new test rig was designed, built, characterized, and used for accurate preparation of HNCO under process conditions to extend the basic molecular spectroscopic data. The test rig was connected to instrumentation (FTIR and TDL spectrometer) to acquire background-free reference spectra of HNCO at various temperatures, pressures, HNCO and water mole fractions. These spectra were then used to extract the line areas of HNCO by IHM and to corelate these to the temperatures, pressures, and absolute HNCO mole fractions determined from the experimental setup. This now allows a high temporal resolution (kHz), quantitative determination of HNCO under relevant process conditions (uncertainty of 10 ppm∙m) by using TDLAS.
Publications
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„Development of a LASER based insitu HNCO detection system for SCR systems”, Gordon Research Conference - Laser Diagnostics in Energy and Combustion Science, 23-28 June 2019, Les Diablerets, CH
Luigi Biondo, Hardy Hamel, Philipp Hönig, Joanna J. Mikolei, Steven Wagner
