Gas nitrous acid (HONO) analyzer is a professional equipment used for detecting and quantifying this gas. The following is a comprehensive analysis of its influencing factors:
1、 Sensitivity to environmental conditions
Temperature and humidity fluctuations: HONO measurement is susceptible to changes in environmental temperature and humidity. Some instruments are equipped with temperature and humidity compensation functions, which need to be enabled to optimize data accuracy.
Light conditions: Due to its high chemical activity, HONO can only survive for 30 minutes to 2 hours under light conditions during the day. Therefore, it is advisable to avoid installing the instrument in areas with direct sunlight to prevent rapid decomposition of HONO due to light exposure, which may affect the accuracy of the measurement.
Vibration and airflow interference: The instrument should be installed in a well ventilated area away from strong vibrations or airflow interference to avoid mechanical vibrations or airflow disturbances affecting sampling stability.
2、 The criticality of instrument design and maintenance
Absorption liquid characteristics: Traditional LOPAP instruments use strongly acidic absorption liquids (such as a mixture of sulfonamide and hydrochloric acid, pH ≈ 0), which can effectively convert HONO to NO ₂⁻, but are highly corrosive, easily damaging the vacuum pump, and difficult to treat waste liquids. The new instrument has been improved to use neutral non corrosive solutions to reduce equipment losses.
Calibration and stability: Regular calibration is the foundation for ensuring accuracy. Offline calibration uses nitrous acid standards, while online calibration automatically generates HONO standard gas. Lack of calibration can lead to data drift; In addition, timed zero calibration can effectively check the stability of the instrument and whether the real-time concentration obtained is accurate.
Maintenance work: Regularly clean sensors and internal components to prevent the accumulation of pollutants from affecting sensitivity.
3、 Optimization of configuration of operational parameters
Sampling mode and frequency: Continuous mode is suitable for real-time monitoring, while intermittent mode samples at set intervals. Insufficient time resolution may miss short-term peak concentrations.
Flow control: The flow rate of environmental atmospheric samples entering the vacuum reaction chamber needs to be precisely controlled to ensure sufficient reaction with iodine ions.
To ensure accurate monitoring of gaseous nitrous acid (HONO) analyzer, it is necessary to comprehensively control all influencing factors to support the analysis of atmospheric pollution causes and governance decisions.