Research On The Key Technology Of Sensor Array For Odor Gases Detection

With the degree of concern for environmental quality improving, odor gas monitoring is becoming an important part of environmental monitoring. The waste water and gas from the industry, odor gases from garbage accumulation seriously irritate people’s olfactory organ, and impact people’s physical and mental health. Therefore, to reduce the emission of odor gases in the air and control the content of odors gases is imperative to reduce air pollution. The primary task to solve the odor pollution is to achieve real-time monitoring and analysis of the content of odor gases.This thesis summarized the methods of odor gas detection and the research progress and direction of development of sensor array at home and abroad. Then, based on the principle of the sensor array, this paper developed a odor gas detection system consisting of different types of gas sensors. Based on the key monitoring gas species of national standards, and comparing the characteristics of different gas sensors, we ultimately selected MOS, electrochemical and PID sensors as an array.The odor gases detection system includes the sensor array, the gas chamber, the lower machine and PC. The lower machine to the MCU of C8051F020 the core completes the gas sampling, processing timing controlling, the acquisition and processing sensors signal,and data communication with the PC. PC system, based on LabVIEW, is used for data acquisition and data analysis, receiving the signal from the lower machine displaying real-time dynamic curve and human-computer interaction. Based on the analysis of the output characteristics of different sensors, the paper uses the difference method and curve fitting method for data processing and quantitative analysis. And the thesis states in detail,hardware development, software programming of the lower machine and software programming of PC.Experimental part of this thesis tested the stability and repeatability of sensor detection system; and analyze the effect of the flow properties on the system performance.At last the issue studied the response relationship between the single component gas and sensor array system, and completed the response curve fitting. The results shows that the system has good repeatability and good detection accuracy, the detection accuracy of a single gas within 7%. The system can meet the basic requirements of odor gas detection.Finally, the paper described the present deficiencies and improvements in the research work, and discussed the future development direction of the research.