Design Of Benzene Gas Early Warning System Based On Wireless Sensor Network

With the rapid development of China’s economy and the continuedstrengthening of safety awareness, the monitoring system of poisonous gas usedin chemical industry will become informatization and networking. Benzene is animportant chemical raw material, but it also is a serious threat to the lives andproperty of the people because it’s carcinogenic and explosive. This paperanalyzes the development of benzene detection technology and wireless sensornetworks at home and abroad. Combined with actual production needs andnational requirements, this paper designed the system based on wireless sensornetwork.This paper adopted the Wi-Fi self-organized network as wirelesscommunications core architecture to build the star network topology. Thecommunication protocol was optimized by using the synchronous dormancymechanism and network coverage was optimized by using AFSA optimizes. Thissystem adopted high-power wireless bridge as a data relay, and it broughtreceived data to machine interface. A friendly upper monitor can know real-timechanges in the concentration of the field. It also has an alarm event query history,concentration curve plotted within a certain time, set the alarm value for eachmonitoring point and other functions.The system’s hardware is based on MSP430F149processor. This paperdesigned transmitter circuit of electrochemical sensor, power module, processormodule, and display and alarm module. The modular design enhances theflexibility and scalability of the system. This paper also developed the underlyingdrivers and completed temperature compensation and concentration fitting bysoftware. Software compensate makes the detection data more reliable.This system was carried out the performance test, such as systematic error,repeatability, response time, communication distance, packet loss rate and other performance tests, and environmental experiments for the system. Finally, thispaper analyses the leakage early warning model and simulates the effect ofdifferent environmental factors on leakage on MATLAB.Experimental results show：System covers a radius of up to500meters,measurement error does not exceed5%, its resolution is1ppm, its response timeis less than23s, and its relative standard deviation of reproducibility is less than2%. After optimizing of communication protocols, work time extension of thesystem was nearly100hours. The system meets the design requirements and hasgood market prospects.