title: Multipass open-path Fourier-transform infrared measurements for nonintrusive monitoring of gas turbine exhaust composition.
abstract: The detection limits for NO and NO2 in turbine exhausts by nonintrusive monitoring have to be improved. Multipass mode Fourier-transform infrared (FTIR) absorption spectrometry and use of a White mirror system were found from a sensitivity study with spectra simulations in the mid-infrared to be essential for the retrieval of NO2 abundances. A new White mirror system with a parallel infrared beam was developed and tested successfully with a commercial FTIR spectrometer in different turbine test beds. The minimum detection limits for a typical turbine plume of 50 cm in diameter are approximately 6 parts per million (ppm) for NO and 9 ppm for NO2 (as well 100 ppm for CO2 and 4 ppm for CO).
authors.affiliation: Institute for Meteorology and Climate Research, Atmospheric Environmental Research, Forschungszentrum Karlsruhe GmbH, Kreuzeckbahnstrasse 19, Garmisch-Partenkirchen 82467, Germany. Klaus.schaefer@imk.fzk.de
authors.forename: Klaus
authors.initials: K
authors.lastname: Schäfer
authors.forename: Klaus
authors.initials: K
authors.lastname: Brockmann
authors.forename: Jörg
authors.initials: J
authors.lastname: Heland
authors.forename: Peter
authors.initials: P
authors.lastname: Wiesen
authors.forename: Carsten
authors.initials: C
authors.lastname: Jahn
authors.forename: Olivier
authors.initials: O
authors.lastname: Legras
mesh_terms: D000465:Algorithms; D004784:Environmental Monitoring / Q000379:methods*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D009569:Nitric Oxide / Q000032:analysis*; D009609:Nitrous Oxide / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017550:Spectroscopy, Fourier Transform Infrared / Q000295:instrumentation* / Q000379:methods*; D001335:Vehicle Emissions / Q000032:analysis*
chemical_list: D001335:Vehicle Emissions; D009569:Nitric Oxide; D009609:Nitrous Oxide