Aerosols refer to multiphase systems composed of the atmosphere and suspended solid and liquid particles. Although aerosols are only a small component of the Earth's atmosphere, their impact and role on the geosphere and biosphere cannot be underestimated. The chemical composition of aerosols is complex, and their particles can serve as reaction surfaces or catalysts in the atmosphere, as well as receivers for many gas-phase substances. The chemical substances carried by atmospheric aerosols, especially industrial pollutants, can be transported over long distances of hundreds to thousands of kilometers under the influence of wind systems. The impact of atmospheric pollution knows no borders or regions and is a global problem. Its serious harm to the human living environment has become increasingly severe. When evaluating the impact of aerosols on human health and the environment, it is necessary to understand how aerosols are formed and how their concentration and composition vary with day, night, and season.

Analysis principle:

The ambient air is filtered by a vacuum pump at a constant flow rate through a particle size filtration sampling port (such as PM 1.0, PM 2.5, or PM 10) to screen for the largest particle size (PM). Soluble gases are absorbed by a rotating liquid film cavitation device (WRD), and water-soluble ions in aerosols are captured by a steam jet aerosol collector (SJAC). The absorbed soluble gas solution and the captured water-soluble ion solution are then separately introduced into two sets of ion chromatography (IC), and the anions and cations are quantitatively analyzed to monitor the ambient air quality. This system has high accuracy and can achieve a detection limit of 6 to 0.1 μ g/m3 without the need for pre concentration.

Can be used for both online monitoring and laboratory instruments

During online monitoring, an analysis and detection data can be generated every 60 minutes, including the diurnal variation and trajectory model of pollution events

Monitoring results, trend charts, etc. can be controlled and accessed locally or remotely.

Can remotely view system status and performance, and adjust instruments if necessary.

Monitoring gases: hydrochloric acid (HCl), nitric acid (HNO3), nitrous acid (HONO), sulfur dioxide (SO2), ammonia (NH3)

Monitored aerosol ions: chloride (Cl -), nitrate ion (NO3-), sulfate ion (SO42-), ammonium ion (NH4+), potassium ion (K+), calcium ion (Ca2+), magnesium ion (Mg2+)




Wet Rotating Denuder (WRD)

The rotating liquid film cavitation device (WRD) consists of two coaxial glass tubes, and diluted H2O2 solution is continuously added to the annular space between the two glass tubes. When the coaxial glass tube rotates, a continuous and uniform liquid surface will be formed on the outer wall of the inner glass tube and the inner wall of the outer glass tube. The ambient air passes directly between the glass tubes, and due to its much higher diffusion coefficient than aerosols, nearly 100% of acidic gases and NH3 gases are absorbed from the gas mass. The absorbed gas solution is sampled and analyzed.

Due to the air flow velocity, the design of WRD enables the formation of advection in WRD, and aerosols and other particulate matter enter the steam jet aerosol collector (SJAC) through WRD.






Steam Jet Aerosol Collector (SJAC)

After WRD, the ambient air is removed of water-soluble components from the gas and enters the steam jet aerosol collector. The introduction of supersaturated vapor causes aerosols to become larger and heavier droplets. Afterwards, the airflow enters a cyclone separator, which absorbs aerosols into the aqueous solution through inertial separation. After the aerosol solution containing dissolved inorganic ions continuously flows out from the bottom of SJAC and is collected, it enters ion chromatography for quantitative detection along with the previous gas sample.