气体易燃特性受限空间实验测定方法的研究

Research on Detection Method of Gas Flammability in Confined Space

气体易燃特性是化学危险品分类及标记全球协调制度(GHS)中安全数据表制定以及GB 20577-2006中气体危险性分类的重要依据,由易燃气体爆燃浓度上、下极限值描述。目前在化学品性质数据库中仅有部分单元气体的易燃特性信息,对于多元混合气尚无有关易燃性极限的描述,传统多元气体易燃性极限的经验公式估算法存在误差大的特点。本文研制了基于燃爆状态特征信息提取与分析的受限空间内气体易燃性极限自动检测系统。在引入流量修正项的气体浓度增量调节技术的基础上,提出了一种气体易燃性极限的离散逼近搜寻法,运用多传感器联合燃爆状态辨识技术实现火焰精确捕捉。多种典型试样测定结果表明:本系统气体易燃极限的测量不确定度优于2%。

Gas flammability is an important basis for establishment of the Safty Data Sheet in the Globally Harmonized System of Classification and Labelling of Chemicals （GHS） and classification of gas hazardous-characteristic according to GB 20577-2006, which is normally described by gas flammability-limits. At present, only the flammability-limits of a few typical gases can be retrieved in chemical nature databases. There is no information about flammability of gas mixtures with traditional method based on empirical formulas inducting biggish error. This paper design and develop a novel automatic system for gas flammability-limits detection, which is based on characteristic-parameters extraction and analysis through deflagration in confined space. The concentration increment regulation introducing flow correction and the discrete approximation method for searching gas flammability-limits is presented. With technique of multi-sensor characteristic-parameters recognition, flame is captured accurately. Experiments on typical gases and gas mixtures show that the measure uncertainty is within 2%.