Intelligent PM2.5 Sensors

Nov 30, 2022

With the progress of industrialization, the scale of heavily polluting industries such as petroleum, chemical industry, electric power, and metallurgy continues to expand, and the related sewage treatment doesn’t meet the standard, resulting in an intensified trend of overall air pollution. Heating in winter in northern regions and the rapidly increasing number of motor vehicles has caused an increase in the concentration of particulate matter in the atmosphere. PM2.5 is fine particulate matter in the atmosphere, and the diameter of the particles is small, less than or equal to 2.5um. Affected by pressure, temperature, geographical environment and other conditions, PM2.5 particles can be suspended in the atmosphere for a long time. The higher the concentration is, the more serious the air pollution becomes at this time. PM2.5 fine particulate matter can be converted from sulfur and ammonia oxides. This particulate matter seriously affects people's health due to its good activity, large area of ​​existence, and easy attachment to other types of toxic and harmful substances.
 
The current detection methods for PM2.5 mainly include vibration balance, electrochemical detection and weighing, but most of the PM2.5 particle detectors manufactured based on the above methods have bad detection sensitivity, single function, and low degree of intelligence. Large-scale detection instruments with multiple particle and gas detection functions are relatively expensive, bulky, and not portable, which are not suitable for using in public places, offices, and homes.
 
Laser technology is an important invention in the 20th century. Since the beginning of the new century, laser technology has not only developed rapidly in the field of network transmission and communication, but there have also been breakthroughs in the field of measurement and sensing based on its good directivity and coherence. The laser sensor is a sensing device that uses laser technology for measurement. The laser sensor can achieve the purpose of non-contact measurement, with great measuring range, high precision, good anti-interference ability and fast speed.
 
The laser dust sensor uses the principle of laser scattering to photoelectrically convert the signal scattered by PM2.5 particles and amplifies the electrical signal to display the collected concentration of dust. A portable intelligent PM2.5 sensor is proposed. Simulation experiments show that the proposed detector can detect PM2.5 in real-time. It has high precision, wide applicability, small sizes and is easy to carry.
 
 

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