Laser spectroscopic investigation of formation and conversion of isocyanic acid during the aftertreatment of combustion exhaust gases

• Applicant: Dr. Steven Wagner
• Subject Area: Energy Process Engineering
• Term: from 2017 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 341284222

The project aims on the development of an absorption based laser spectrometer for the selective measurement of HNCO (isocyanic acid) in the exhaust of a combustion process (i.e. power plant). The spectrometer will be used to investigate the influence of the exhaust gas mixture, the additive injection (timing, quantity, geometry) as well as the flow conditions (deviation, cross section, turbulence).To increase the potential for further pollutant reduction in recent combustion systems it is necessary to improve the understanding of the process chemistry during combustion as well as exhaust aftertreatment. To get more information about the exhaust gas composition with high temporal resolution, a better diagnostic is needed. Therefore, within this project, a spectrometer for the in situ measurement of HNCO in the exhaust of a combustion process will be developed. To investigate the overall pollutant content, the spectrometer measures with high temporal resolution (ms) and highly sensitive as well as selective. Based on Tunable Diode Laser Absorption Spectroscopy (TDLAS) in the near as well as middle infrared spectral region, recent progresses in the fiber-technology will be used together with a new developed multi-pass-cell (modified White design) to adapt the spectrometer to the high-temperature process. Additionally, FTIR based measurements of the spectroscopic line data of HNCO (line strength, line broadening) will done to realize the accurate extraction of HNCO-mole fractions from the TDLAS measurements.

• DFG Programme: Research Grants