PM2.5 monitoring method based on particle size

Abstract

The invention discloses a PM2.5 monitoring method based on the particle size. A certain amount of dried air to be tested is introduced into a closed container, the closed container is provided with two or more filter nets of different through hole diameters from top to bottom; then, the closed container is closed, standing is performed for 10-30 min, and fine particles in the air to be tested are filtered sufficiently through the filter nets; all the filter nets are taken from the closed container a few days later, the fine particles of the corresponding particle size are extracted from the filter nets of different through hole diameters, and detection analysis is performed. The method is achieved through uniformly-distributed arrayed through holes of different sizes formed in the filter nets by adopting the fine manufacturing technology, the shape precision of the through holes is controllable, and therefore the monitoring result is accurate and reliable.

Description

technical field [0001] The invention relates to the field of chemical analysis, in particular to a particle size-based PM2.5 monitoring method. Background technique [0002] PM2.5 is fine particulate matter, which refers to particulate matter with an aerodynamic diameter less than or equal to 2.5 μm in the atmospheric environment. Although PM2.5 is a very small part of the earth's atmospheric air, it has a great impact on the environment and human health. Inhalable particles of different particle sizes staying in different parts of the respiratory tract will cause different respiratory diseases, and PM2.5 Seriously affect air quality and visibility. Therefore, monitoring PM2.5 based on particle size can be used to specifically analyze the impact of PM2.5 on human health and the environment. [0003] At present, the main methods for monitoring particulate matter in the air based on particle size are: (1) filter membrane weighing method, which is to extract a certain volume ...

AI Technical Summary

Problems solved by technology

[0003] At present, the main methods for monitoring particulate matter in the air based on particle size are: (1) filter membrane weighing method, which is to extract a certain volume of air at a constant rate through a sampler, and the particulate matter in the air is trapped on the filter membrane. The change of weight before and after sampling and the volume of sampled air are used to calculate the concentration; however, some extremely fine particles can still pass through the filter membrane and cause the result to be low, and other substances may also be absorbed by the filter membrane to cause the result to be high

(2) The β-ray method, whose basic principle is to measure the change in the amount of atmospheric particulate matter by using the change in the attenuation of the β-ray emitted by the particulate matter accumulated on the adaptive filter membrane to carbon-14, but the measurement data generally has deviations, and in humid High failure rate in high temperature areas

(3) The micro-oscillating balance method mainly uses the principle of the micro-oscillating balance of the conical element, but the current technology cannot solve the loss of volatile and semi-volatile substances after the sample is heated, resulting in low measurement results

Moreover, the above are all particle size monitoring methods at the level of particle size range, and the monitoring results are relatively rough, and PM2.5 cannot be accurately monitored according to its particle size, which will affect the detection and subsequent analysis of PM2.5

Images