HealthyPhoton's ultra-sensitive ammonia analyzer is based on the second-generation semiconductor quantum cascade laser (QCL) technology. It uses laser's ultra-narrow linewidth to accurately select the high-intensity absorption line of ammonia molecules in the mid-IR region, thereby achieving high-selectivity, high-precision, and robust measurement.
• 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
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.
Customer cases
• Huadian Electric Power Research Institute
• Hebei Province Electric Power Research Institute
• Hebi Ecological and Environmental Monitoring Center
Advantages
• 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.
Parameters
Technology
QCLAS
Specifications
Target species
NH3
Measuring range
0 - 20/50/100/200 ppm
Detection limit
0.1 ppm
Precision
±0.1 ppm (1s integration)
±0.01 ppm (100s integration)
Response time
15 s
Linear error
±1%F.S.
Zero/span drift
±2%F.S.
I/O
Analog output
1 4-20mA output (max. load 750Ω)
Digital output
RS232/RS485
Wireless
4G or WIFI
Data storage
USB port
Sampling
Gas temperature
Ambient to 450°C
Method
Hot and wet
Flow rate
0.25-5 L/min
Heat tracing
60°C - 230°C
Dust requirements
Filtration accuracy < 5um
Work
condition
Power
AC 220V 50Hz (<1.0 kW)
Work temperature
-20°C ~ 55°C
Adaptability
IP54
Dimension &
Analyzer
486×170×340 mm (L×W×H) 〜10 kg
weight
Field Experiment Result
The product has been field-tested in several power plants across China. The product’s reliability, stability, technological advancement, and portability features have been well recognized by users.
Standard gas response & repeatabiliy test:
Comparison & Test
We used a commercial near-infrared laser ammonia analyzer and LGM1600 to make a comparative test. The result shows LGM1600 has faster response time and more accurate measurements. The NIR analyzer has the response time about 85 seconds, and its measurement result has a significant deviation from the actual concentration (maximum 62/.5%). The response time of LGM1600 is about 30 seconds, and the maximum deviation is 1.7%.
Sampling Accessories
LGM1600 is compatible with SmartlineTM or JPESTM portable hot-and-wet sample probe and heated line. Upon request, we can provide SmartlineTM or JPESTM accessories. Refer to SmartlineTM and JPESTM documentations for more details.