Development Of SO₂ Analysis Module For Ultraviolet Fluorescence Atmospheric Micro Station

SO₂ is one of the main pollutants in the atmosphere,and monitoring its concentration is the key work to judge the degree of atmospheric pollution and carry out effective pollution control.At present,most of China's SO₂ detection equipment is imported,and it is expensive and has high maintenance costs.The monitoring of domestic atmospheric grid mini-air stations is mainly based on electrochemical sensor detection,which has electrolyte attenuation,low detection accuracy,and poor repeatability.Short life,etc.In order to improve the monitoring accuracy of the grid-based micro-air station,based on the high-precision,chemical-free ultraviolet fluorescence method,the research and development of the SO₂ analysis module of the micro-air station is carried out.First,this article analyzes the theory of SO₂ advanced optical ultraviolet fluorescence detection method.Based on the Lambert-Beer theorem and multi-wavelength analysis theory,and combined with the classic vertical fluorescence detection model,a SO₂detection unit model is established.The solution of the SO₂ concentration detection model fully explained the proportional relationship between the fluorescence intensity and the SO₂ concentration,which laid the foundation for the rationality of the subsequent research results.Based on previous research,this paper proposes the key issues affecting the miniaturization of SO₂ concentration analysis equipment by ultraviolet fluorescence method,which is described as the optimization study of the miniaturized gas chamber structure of the SO₂ analysis module.This article adopts the method of"decomposition of key issues and targeted optimization",and uses the advantages of multiple optical systems to complement the optical path part of the air chamber.The structural analysis and comparison of the air path part of the air chamber are combined with simulation evaluation and verification to achieve the overall air chamber Miniaturized design of the structure.Based on the theoretical analysis of SO₂ detection and the design of the miniaturized gas chamber,the purpose is to improve the accuracy of SO₂ concentration signal acquisition and reduce system power consumption.Aiming at the low-frequency pulse characteristics of the fluorescent signal generated by the xenon light source when the SO₂molecule is excited,High-input impedance dual-wave linear detection circuit is used as a fluorescence signal acquisition circuit.At the same time,it uses the filtering advantage of the median average filtering algorithm to complete the hardware and software design of the SO₂ analysis module system by using AltimuDesiger13 and Keil uVision5 software.In summary,through theoretical research and simulation analysis,a miniaturized SO₂ analysis module using ultraviolet fluorescence detection is designed.Then,for the system's hardware and software,the method of sub-module debugging and system experimental research is adopted.From the perspective of experimental analysis,the feasibility and applicability of this study are verified.