Solutions - NH3 Monitoring

NH3 (Ammonia) is a colorless gas with a distinctive pungent odor.  NH3 monitoring is essential in coal-fired power plants where NH3 is used to reduce NOx emissions in both SCR and SNCR configurations – which is why a reliable, sensitive and fast response ammonia monitor is vital.  Power plant NO abatement strategies normally involve monitoring NO levels up-steam and down-stream of the NH3 addition point to maximize the reduction of NO.  However, the reduction efficiency rarely is greater than 90% so over addition of NH3 is a distinct possibility.  Over injection of NH3 results in what is called ammonia slip and this excess NH3 can react with other species in the flue gas, such as SO3, resulting in the production of unwanted precipitates that tend to coat the pre-heaters and result in premature aging of the catalysis beds in SCR equipped scrubbers.  This results in higher maintenance cost for the plant, not to mention emissions of environmentally hazardous species.

The TDLAS technology that Unisearch offers is a perfect solution for NH3 monitoring.  It ensure accurate and rapid response to NH3 levels in a variety of harsh environments.  The Unisearch LasIR provides:


  • Reliable, accurate data
  • Rapid response – seconds if desired
  • Multiple location monitoring for poorly mixed flue gases (SNCR) and multiple duct measurements
  • Continuous emissions monitoring of NH3 levels
  • Freedom from interferences by other gases which could result in erroneous data
  • Easier maintenance and improved process control




Contact Us today to set up your own NH3 analyzer for ammonia slip monitoring and keep up with the industry standards.


NH3 Analyzer
TDLAS-based technology for NH3 monitoring.