Study On The Wireless Monitoring System For Gas Leaks In Industrial Environment

Globally,the petrochemical industry generates huge profits each year,while producing a large amount of dangerous gases(flammable,explosive,toxic,etc.)in its production process.Due to improper man-made operation or equipment aging,a large number of gas leaks have occurred,causing huge casualties,economic losses and serious environmental pollution.In order to detect the leakage of hazardous gas in industrial environment,researchers at home and abroad have done a lot of work and achieved some results.However,due to the complexity of the industrial environment,many problems remain to be solved.After investigating the current research status of gas leak monitoring at home and abroad,this article focuses on the detection of gas leak when the gas concentration is below the normal leak alarm threshold(25% Lower Explosive Limited,25%LEL).Two common high concentration thresholds are set at concentrations above 25% LEL while a non-concentration threshold is set at gas concentrations below 25% LEL.In this paper,the existing algorithms are improved.The adaptive multi-sensor data fusion based on support and low concentration anomaly detection based on similarity are completed.The detection algorithm extracted the autocorrelation sequences of the concentration segments and calculates the cosine distance between the features of segments as the as the features.The threshold value is determined by counting the proximity when no leakage occurs,and the status of the current concentration segment is determined.To verify the feasibility of the method,a monitoring system for the detection of gas leaks based on wireless sensor networks is designed.The system consists of Zig Bee wireless sensor terminal,monitoring center and cloud database.This paper completed the simulation analysis of gas diffusion,the collection of data(include concentration,temperature,humidity and pressure)in the node,the data fusion and classification in the coordinator,the implementation of software and hardware in the monitoring center,and the build of remote database.The monitoring center includes the detection function of gas leak,the program of User Interface,the detection of node working status,the transmission of the history data and the warning message.Under the experimental conditions,in this paper,we design a complete experiment for each module and the whole system respectively to conduct the performance test,and analyze the experimental results.The experimental results show that the functions of each module of the system are realized.Under the premise of ensuring a lower false alarm rate,the detection rate of gas leakage is 96.7% and the average detection delay is within 30 s.The design of this article provides a reference solution for the practical application of the environment.The system also needs to further complete the test in the actual industrial environment.