■石油和天然气处理设施中的储罐含有大量易燃化合物。一旦燃料-空气混合物被点燃,它可能会爆发大火或爆炸。对监测空气质量和评估健康风险的兴趣日益浓厚,这使得评估火灾后果成为一个重要问题。大气扩散模型,可以模拟污染物的空间分布,代表了这种评估越来越广泛的工具。
■本研究讨论了与炼油厂中假设的火灾相关的建模研究的设置和结果。
■选择最合适的色散模型后,即拉格朗日模型SPRAY和抽吸模型CALPUFF,讨论了所需输入数据的估计,专注于源变量,代表最不确定的输入数据。将模拟结果与监管限制进行比较,以有效评估环境后果。最后,我们采用敏感性分析来确定影响最大的变量.
■模拟结果表明,地面浓度值远低于所引用的长期限值。然而,最有趣的结果是,根据色散模型和建模的源类型,可以得到不同的结果。此外,敏感性研究表明,源区是最关键的变量,因为它根据建模的源类型确定了明显不同的行为,生产,在某些情况下,选定受体上污染物地面浓度的变异性高达+/-60%。
■根据所选模型和可用于描述发射物理的算法,结果显示对输入变量的敏感性不同。虽然这可以从数学的角度来解释,问题仍然存在,即逐案选择最接近被调查的附带源的真实行为的选项。
■作者声明没有竞争的金融利益。
UNASSIGNED: Storage tanks in oil and gas processing facilities contain large volumes of flammable compounds. Once the fuel-air mixture is ignited, it may break out into a large fire or explosion. The growing interest in monitoring air quality and assessing health risks makes the evaluation of the consequences of a fire an important issue. Atmospheric dispersion models, which allow for simulation of the spatial distribution of pollutants, represent an increasingly widespread tool for this type of evaluations.
UNASSIGNED: The present study discusses the set up and results of a modeling study relevant to a hypothesized fire in an oil refinery.
UNASSIGNED: After choosing the most suitable dispersion models, i.e. the Lagrangian model SPRAY and the puff model CALPUFF, estimation of the required input data is discussed, focusing on the source variables, which represent the most uncertain input data. The results of the simulations were compared to regulatory limits to effectively evaluate the environmental consequences. Finally, a sensitivity analysis was employed to identify the most influential variables.
UNASSIGNED: The simulation results revealed that ground concentration values were far below the cited long-term limits. However, the most interesting outcome is that depending on the dispersion model and the source type modeled, different results may be obtained. In addition, the sensitivity study indicates that the source area is the most critical variable, since it determines a significantly different behavior depending on the modeled source types, producing, in some cases, variability in the pollutant ground concentrations on selected receptors up to +/- 60%.
UNASSIGNED: Depending on the selected model and the algorithms available to describe the physics of emission, the results showed a different sensitivity to the input variables. Although this can be explained from a mathematical point of view, the problem remains of choosing case by case the option that best approximates the real behavior of the incidental source under investigation.
UNASSIGNED: The authors declare no competing financial interests.