【摘要】 目前对危险气体泄漏防护区域的划分方法主要为定性方法,难以对具体场景定量表征,进而无法用于风险防控系统的设计规划。本文在等价气云理论的基础上,基于爆炸事故后果风险评估,提出一种定量划分气体防护区域的方法。综合考虑气体泄漏概率、风速风向联合分布概率等现场特征要素,运用高斯扩散模型,得到气体泄漏扩散的等价气云体积以及气体泄漏扩散风险集合,并进行泄漏场景筛选。针对扩散风险较大的场景进行点火概率分析,利用多能法计算气云爆炸影响范围,对气云爆炸事故进行风险评估得到爆炸事故后果风险集合。在ALARP标准与火气系统探测器场景覆盖率的指导下,依据不同装置区域的风险值确定气体防护区域等级定量划分标准。通过某LNG接收站案例分析,可定量得到不同装置的防护区域等级,实现针对具体泄漏场景的气体防护区域等级定量划分。数值计算表明,气体防护区域定量划分可为火气系统探测器布设提供理论支持。更多还原

【Abstract】 To divide the prevention area of hazardous gas leakage, qualitative method is mainly used. But it is difficult to characterize specific scenes by qualitative method. It cannot be used to design and plan the risk prevention and control system. A method of dividing gas protection area quantitatively is proposed based on equivalent gas cloud theory and risk assessment of explosion accident. The equivalent gas cloud size and risk set of gas leakage dispersion can be obtained by Gaussian model and considering the on-site features such as gas leakage probability, wind speed and direction joint distribution probability and so on.Then the gas leakage scenes can be selected by according to risk grade. Aiming at the scenes with higher grade of dispersion risk, the ignition probability analysis is carried out. The multiplication method is used to calculate the influence range of gas cloud explosion. The risk set of the explosive consequences can be analyzed by using risk assessment of accidents. The quantitative division standards of gas protection area are determined by risk values for different device areas under the guidance of ALARP standard and scene coverage of fire & gas system(FGS) detector. Through one LNG receiving station case analysis, the protection area grade of different devices can be quantitatively obtained. Aiming at specific leak scenarios, the quantitative classification of gas protection zones can be achieved. The numerical calculation shows that the quantitative division of the gas protection area can provide theoretical support for the detector deployment of FGS.更多还原