Chemical Pipeline Leakage Detection And System Integration Based On Double-layer Model

As a bridge of various unit equipment in industrial production,pipelines play a vital role in ensuring the stable operation of production.However,because of factors such as materials and human factors,once the pipeline leaks,it will cause huge economic losses and seriously affect chemical production safety.At present,most of the research work is mainly on long-distance transportation pipelines.However,due to the widespread characteristics of chemical pipelines,such as short straight sections,many branches,and complex shaped components,there are few methods to study the leak of the chemical pipeline.Therefore,in order to effectively realize the leak detection and accurate positioning for chemical pipelines,based on the existing methods,this paper studies a chemical pipeline leakage detection and positioning method,simulates and analyzes it by Flowmaster software,and designs a set of experimental devices to achieve system integration,using the designed devices to carry out detection method verification and system performance test analysis.The main research contents of this article include:(1)Based on the pipeline transient flow theory,the modeling method of the chemical pipeline transient model is proposed.To establish a model for chemical pipelines,this paper firstly introduces the pipe elbow resistance equation into the real-time transient model(RTTM),and at the same time establishes a real-time transient model for chemical pipelines in conjunction with the Brunone model,and then uses particle swarm optimization to real-time transient model for chemical pipelines parameters optimized in real time.The parameter optimization process mainly collects real-time data of the flow and pressure at the first end of the pipeline,calculates the first-end flow and pressure through the model to obtain the parameter distribution along the pipeline,and then calculates the relative error between the pressure and flow collected at the end of the pipeline and the calculated value in real time as the fitness for the particle swarm optimization algorithm,the parameters are optimized by reducing the fitness to a prescribed threshold.Finally,Flowmaster simulation software is used to verify the applicability of the model;(2)In order to realize the leak detection and location of chemical pipelines and improve the accuracy of detection,this paper proposes a double-layer model leak detection and location method based on the real-time transient model of chemical pipelines.The two-layer model is a two-layer structure that integrates multiple sequential probability ratio test(M-SPRT)negative pressure wave positioning,mass flow balance,and anti-transient analysis.First,the one-layer model detects the pressure signals collected at the head and end through multiple sequential probability ratio test(M-SPRT)combined with the negative pressure wave positioning method,and initially locates,and at the same time passes the flow signals collected at the head and end The mass flow balance method preliminarily judges the amount of leakage;then the second layer model uses the initial location and leakage amount determined by the first layer model to perform an anti-transient analysis(ITA)on the real-time transient model of the chemical pipeline established in this paper,and finally obtains the specific Information leakage and location.Among them,the anti-transient analysis is mainly implemented by the chaotic particle swarm optimization algorithm.This algorithm can ensure that the chemical pipeline model does not fall into the local optimum during the anti-transient analysis and has a high rate of false negatives and false alarms.The layer model preliminarily determines the amount of leakage and the location of the leakage,which reduces the search space of the second layer for anti-transient analysis to a certain extent.Compared with a single anti-transient analysis method,it has the advantages of fast convergence speed and high positioning accuracy.Efficient judgment and accurate positioning of leaked information can be achieved;(3)In order to verify the effectiveness of the detection method and the collection and processing of the detection information,a set of experimental equipment was designed and system integration was carried out.The entire experimental device system is divided into hardware and software parts.The hardware part includes pipelines,pumps,valves,and data acquisition system modules.The software part includes on-site monitoring,signal processing,and leak detection and positioning modules.The experiment of the experimental device shows that the real-time transient model of the chemical pipeline has higher accuracy in simulating the on-site pipeline,and the double-layer model has better real-time performance and accuracy in the detection and location of chemical pipeline leakage.Through the establishment of the chemical pipeline model,integration of the double-layer model in the leak detection with location method,and the application of the experimental device system,it is conducive to further in-depth study of the related methods of chemical pipeline leak detection and location.The practical application development has provided better engineering reference value and provided the necessary technical means for the safety production of chemical enterprises.