Risk mitigation in production facilities has been an issue of great interest for decades, especially in activities which represent a serious hazard to human health, environment and industrial plants. Dust explosions are a major hazard in many industrial processes: only in the first part of 2019 (January–June) 34 dust explosions, mainly due to organic powders, occurred worldwide. An explosion may take place whenever there is the presence of combustible dusts, which are frequently generated by activities such as grinding, crushing, conveying and storage. Currently, a relatively expensive experimental test, carried out into a 20-L Siwek apparatus, is used to address the order of magnitude (class) of explosive dust: this piece of information is referred to as the deflagration index, K_st. At the current state, only a few pioneering models have been developed in order to predict the value of the K_st as a function of some relevant properties of the dust: e.g. particle size distribution (PSD), humidity, thermal conductivity, etc‥ Most of these models condense the information about the PSD of a given dust into an average value, referred to as D₅₀. In this work, a kinetic free mathematical model aimed at predicting the deflagration index for organic dusts is presented. This model, unlike the older ones, considers the whole particle size distribution for the computation of the deflagration index. In order to be implemented, only a single experimental K_st value (which works as a reference) and a particle size analysis on the dust are required. The model was validated using the whole granulometric distribution of three different organic powders (fosfomycin, sugar and niacin). In addition, the same estimations were done by considering only the D₅₀ data. It was noticed that, for highly polydispersed dusts, results were less accurate with respect to those obtained using the complete PSD, highlighting the importance of considering a complete granulometric distribution for process safety purposes.

几十年来，降低生产设施中的风险一直是人们非常关注的问题，特别是在那些对人类健康，环境和工业工厂构成严重危害的活动中。粉尘爆炸是许多工业过程中的主要危害：仅在2019年上半年（1月至6月），全球发生了34次粉尘爆炸，主要是由于有机粉末。每当存在可燃粉尘时，都可能发生爆炸，这些粉尘通常是由诸如磨碎，压碎，运输和存储等活动产生的。当前，在20升Siwek设备中进行的相对昂贵的实验测试用于解决爆炸性粉尘的数量级（类）：这条信息称为爆燃指数K _st。在当前状态下，只有很少的开拓性模型已经以预测所述K的值开发_ST例如粒度分布（PSD），湿度，热导率等‥最：作为灰尘一些相关特性的函数这些模型中的一个将有关给定粉尘PSD的信息压缩为平均值，称为D ₅₀。在这项工作中，提出了一个旨在预测有机粉尘爆燃指数的无动力学数学模型。与较旧的模型不同，该模型考虑了整个粒度分布以计算爆燃指数。为了得以实施，只有一个实验_Kst值（作为参考）和灰尘的粒度分析是必需的。使用三种不同有机粉末（磷霉素，糖和烟酸）的整个粒度分布验证了该模型。此外，仅考虑D ₅₀数据即可进行相同的估算。值得注意的是，对于高度多分散的粉尘，其结果相对于使用完整PSD所获得的结果而言较不准确，突出了出于过程安全目的考虑完整粒度分布的重要性。