Real-time detection of atmospheric fine particle mass concentration based on laser forward small angle scattering

Abstract

The level of fine particulate air pollution exposure is positively correlated with the death rate of individuals infected with COVID-19. Monitoring is the first step to prevent fine particulate pollution. The instrument based on light scattering method to detect particle concentration has unparalleled advantages over other instruments due to its rapidity, real-time and low cost. Traditional light scattering instruments are limited by the light absorption and particle properties of particles, and their ability to monitor some particles with strong light absorption is greatly reduced. Moreover, when the measured environment is greatly different from the calibration environment, the measurement results often have large errors. In this research, an instrument is designed to detect the forward scattering of light from small angles of particles. It can monitor the number concentration of particles in the environment in real time in four particle size ranges (PM1, PM2.5, PM4 and PM10) and convert it into the mass concentration of particles. By using the simulated atmospheric smoke box and the standard instrument to conduct a field comparison experiment, the reliability and stability of the measurement results are verified.