Integrated leakage detection and localization model for gas pipelines based on the acoustic wave method

With the development of natural gas transportation systems, major accidents can result from internal gas leaks in pipelines that transport high-pressure gases. Leaks in pipelines that carry natural gas result in enormous financial loss to the industry and affect public health. Hence, leak detection and localization is a major concern for researchers studying pipeline systems. To ensure the safety and improve the efficiency of pipeline emergency repair, a high-pressure and long-distance circular pipe leakage simulation platform is designed and established by similarity analysis with a field transmission pipeline, and an integrated leakage detection and localization model for gas pipelines is proposed. Given that the spread velocity of acoustic waves in pipelines is related to the properties of the medium, such as pressure, density, specific heat, and so on, this paper proposes a modified acoustic velocity and location formula. An improved wavelet double-threshold de-noising optimization method is also proposed to address the original acoustic wave signal collected by the test platform. Finally, the least squares support vector machine (LS-SVM) method is applied to determine the leakage degree and operation condition. Experimental results show that the integrated model can enhance the accuracy and precision of pipeline leakage detection and localization.     

CIMAH — where are we now

This paper, presented at Guildford in April 1988, outlines the UK control strategy for Major Chemical Hazards, in a European context. The current legislative background is described, followed by an indication of potential changes to reflect international initiatives. The paper is a presentation of current CIMAH issues.     

Modelling Complex Pipeline Network Leak Detection Systems

A novel model for detecting leaks in complex pipeline network systems has been developed. The model derives from the theory of Liapunov stability criteria. A leak is detected if the resulting eigenvalues from the deviation flow matrix have values less than a predetermined value. An advanced mesh network algorithm was used to decompose the complex pipeline network system into sub-networks. The flow model (equations of motion and continuity) which incorporates a leaking factor, k_L, is solved by a numerical technique that uses the method of characteristics and an implicit finite function. The unsteady state flow matrix of the complex pipeline network system was analysed using a modified Hardy Cross algorithm, where the velocity and pressure were computed for each node and pipeline loop in the complex network. The plots for the characteristic pressure and velocity eigenvalues show that pressure measurements are faster parameters for leak detection than volume measurements. Volume measurements appear to be suitable for larger leak systems and longer response time.     

模糊综合评价法在液氯运输过程安全性评估的应用

将模糊综合评价方法和层次分析法用于危险化学品运输过程安全性评估,综合考虑在过程中危化品、人、车、路、环境等五个方面因素对整个过程安全性的影响,得到运输过程安全性等级。运用现有的泄漏模拟公式定量计算发生泄漏事故后所产生的危险区域,为人员疏散提供了决策帮助。最后以液氯运输过程为例进行安全评估,并计算泄漏后危险区域的范围。     

液化石油气球罐泄漏危险的预防和控制探讨

阐述了液化石油气球罐的特点。对液化石油气球罐的泄漏危险性进行了分析,主要存在的泄漏危险有泄漏物质易燃易爆、易发生泄漏、受热易膨胀导致泄漏、泄漏气体易积聚、泄漏事故具有隐蔽性、泄漏物质具有毒害性。根据液化气泄漏危险性分析,提出了预防和控制液化石油气球罐泄漏危害的安全措施:加强设备质量管理,杜绝泄漏现象;合理设置球罐,降低泄漏风险;规范安全操作,减少泄漏量;防止泄漏气体积聚;设置防泄漏安全装置;及时发现泄漏;设置消防给水及灭火设施;妥善处理泄漏事故。     

危险品的GPS运输监控技术现状分析

频发的危化品运输事故说明,危化品运输环节的技术化监管仍存在重大的漏洞和不足.从分析导致运输事故的原因出发,提出通过建立以GPS定位技术为基础的智能化全程监控危化品的运输系统,并在城市化进程中不断推广,才能降低事故率,营造出持久、稳定、安全的运输环境.     

运用先进监控技术确保油气管道安全

介绍了我国油气管道安全现状,提出了解决油气管道事故频发应采取立法保护、监控保护和人防保护等3种主要措施,着重介绍国内石油石化行业应用的4种油气管道泄漏自动检测技术。     

一起发油管线泄漏事故原因及应急处置分析

分析了一起埋地发油管线泄漏事故的成因,根据国家安全生产监督管理总局和中国石化对突发事件的应急管理要求,指出本起突发事件应急处置中存在着风险识别不充分、处置不当、应急力量缺乏等问题,并进一步提出对策与建议。     

10kt/a甲醇合成精制装置安全性评估与消防设计

甲醇合成精制装置一旦发生泄漏事故,将会对厂内甚至相邻地区的人员生命、机械设备及环境造成严重威胁。为了有效预防事故的发生,通过ALOHA化学品泄漏扩散模拟软件对甲醇合成精制装置进行危险性辨识和评价。结果表明,热辐射危害是池火灾、BLEVE火球的主要危害;BLEVE火球和中毒事故危害范围较广:在BLEVE火球的热辐射中暴露60 s造成死亡的距离均超过100 m,泄漏孔径达5cm时毒气的体积分数达ERPG-3值的距离达326 m。因此,消防设计是甲醇精制装置安全系统设计的重要组成部分。根据《石油化工企业设计防火规范》及相关消防标准规范对该甲醇合成精制车间进行相应的消防系统设计,并用Auto CAD专业绘图软件绘制消防设施的布置图,为施工单位提供依据,从而提高甲醇合成精制装置的安全性,减少人员伤亡事故的发生。