Photoacoustic NH3 Monitoring with Waveguide CO2 Lasers

  • M. Hammerich
  • A. Ölafson
  • J. Henningen
Part of the Ettore Majorana International Science Series book series (EMISS, volume 54)


Ammonia is not a natural constituent of fossil fueled power plant emission, but nitrogen oxides and sulphur dioxide are. In various schemes for denitrification and desulphurization, ammonia is introduced either as a reducer of NOX as in the Selective Catalytic Reduction (SCR) process or as a neutralizer for acids developed in the denitrification, as in the corona based CORONOX process. In either case one wants to monitor the efficiency of the process and to be able to document compliance with NH3 emission limits. Thus, there is an increasing need for ammonia measurements in smoke stacks, and the monitor needs to be:
  • moderately sensitive, corresponding to 1 ppm detection limit;

  • very selective, so as to monitor NH3 regardless of known and unknown components in the smoke;

  • automatic;

  • moderately fast, corresponding to 1 measurement per 10 minutes for normal monitoring, and 1 per minute for reactor characterization and process optimization.


Selective Catalytic Reduction Free Spectral Range Photoacoustic Signal Photoacoustic Cell Laser Spectrometer 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Plenum Press, New York 1990

Authors and Affiliations

  • M. Hammerich
    • 1
  • A. Ölafson
    • 1
  • J. Henningen
    • 1
  1. 1.J. C. Orsted Institute Physics LaboratoryUniversity of CopenhagenKöbenhavnDenmark

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