HealthyPhoton - Model LGM1600 -Portable NH3 Analyzer

The ammonia concentration of 2~3 ppmv in flue gas is a great challenge for the accurate estimation of ammonia slip and DeNOx process in most coal-fired power plants. Most of the existing near-IR laser spectroscopy based monitors cannot achieve reliable accuracy under harsh field conditions at the coal-fire SCR outlet. The traditional in-situ cross-duct sensor has an issue that the laser beam cannot penetrate due to high dust. In the meanwhile, vibration, expansion, and contraction of the duct affect the accuracy and the stability of the laser beam, leading to loss of signal, which increases maintenance costs.

Recently, some products have used extractive sampling+near-IR diode laser+multi-pass absorption gas cell technology to make use of a long optical path to compensate for the weak absorption of near-IR spectral lines. However, the long-pathlength absorption cells are not suitable for the severe working conditions of high dust, high temperature and high ammonium bisulfate salt (ABS). After a long-term operation, the cleaning and beam re-alignment of the optical cell greatly increase the difficulty and maintenance cost.

• High precision and no cross-interference from other molecules
• Short optical path that avoids maintenance-demanding multiple reflection cells
• No need for light alignment and lens cleaning
• Reliable optomechanical structure not affected by the thermal deviation
• >230? high-temperature sampling
• Direct measurement results that are not affected by pretreatment
• Ultra-small size for easy integration

• Huadian Electric Power Research Institute
• Hebei Province Electric Power Research Institute
• Hebi Ecological and Environmental Monitoring Center
  

• QCL+TDLAS technology has a measuring range of 0-20ppmv and accuracy up to 0.01ppmv;
• It does not need the long-pathlength multi-pass absorption gas cell, thereby reducing the difficulty of maintenance and extending the maintenance period;
• The direct high-temperature extractive sampling method eliminates walk-off beam challenges faced by in-situ cross-duct laser-based sensors;
• The sampling pipeline length is less than 3 meters, which reduces the signal delay and improves the real-time feedback for DeNOx optimization;
• The sample flow rate can be as low as 250 mL/min, which can reduce probe wear and reduce maintenance costs;
• Mid-IR laser spectroscopy provides an optional simultaneous measurement of NH3 and NOx with a single probe. A single analyzer combined with the grid measuring method can assess the NH3-NOx molar ratio distribution.