Design And Research Of Outdoor Multi-parameter Ambient Air Quality Monitoring System

With the gradual advancement of industrialization,China's atmospheric pollution problem has become more and more serious,and the country's requirements for the prevention and control of atmospheric pollution are becoming higher and higher.Particulate matter and toxic gases are harmful to the environment and human body.If the concentration of particulate matter is too large,it will cause smog and have a great impact on human health.Among the gaseous pollutants,the emitted sulfur dioxide will stimulate the human respiratory tract,induce various respiratory diseases,and at the same time it will cause damage to vegetation,etc.The emitted nitrogen oxides will combine with other pollutants to produce photochemical smog pollution.In order to deal with the prevention and control of atmospheric pollution,the State Council and local governments have issued corresponding policies.At present,local environmental monitoring mainly relies on the air quality data released by the national environmental air quality automatic monitoring station.The number of national environmental air quality automatic monitoring stations is small,and the distance between different stations is long.It can only respond to major environmental pollution problems,and it cannot meet the management of secret discharge of pollutants by factories at this stage.At the same time,the cost of the national environmental air quality automatic monitoring station is relatively high,covering a large area,and it is troublesome to select monitoring points.In this situation,a new type of multi-parameter,miniaturized,high-resolution,and easy-to-install ambient air quality monitoring equipment is urgently needed.The outdoor multi-parameter ambient air quality monitoring system designed and studied in this paper can provide real-time,accurate and intuitive data information.It is suitable for large-area grid dense distribution and can be widely used for long-term continuous monitoring of ambient atmospheric particulate matter concentration.It can be also used for typical ambient air quality monitoring,such as industrial and mining areas,indoor air quality monitoring,etc.The ambient air quality system uses STM32F103VET6 as the main control chip to realize the control and data interaction of various sensors and modules.The sensor used for particle measurement is OPC-N2from British Alphasense,and the gas sensor is electrochemical sensor also from British Alphasense.Compared with the measurement of gas and particulate matter in the national ambient air quality automatic monitoring station,the sensor we choose is small in size and low in cost,and is suitable for large-area layout.The measurement system is also equipped with temperature,humidity,wind speed and direction sensors,which can be used for outdoor data storage through SD card or real-time data transmission through wireless communication module.The whole monitoring system is built on the designed instrument.The shell design of the instrument is easy to fix on the column pole,which can guarantee the waterproof,and is suitable for long-term outdoor measurement.The designed outdoor multi-parameter ambient air monitoring system has a good correlation with the data released by the national ambient air quality automatic monitoring station after long-term outdoor operation.Among them,the long-term monitoring data of ozone,sulfur dioxide,PM_2.5,PM₁₀is compared with the data of the national ambient air quality automatic monitoring station.The correlation coefficients are all above 0.8,which has a strong correlation.The correlation coefficient of the carbon monoxide monitoring data comparison is also above 0.7.