The quantitative detection of pollutants in industrial emissions, in particular the emissions of biomass burners, requires different types of analyzers. Optical devices are usually sensitive to the transparency and dirtiness of the exhaust gases, so optical measurements are normally carried out by extracting the samples from the stacks. This paper has a twofold aim. First, we will prove that the molecular composition of the exhaust mixture (in particular the concentration of water and carbon dioxide) can deeply affect the outcome of optical analyzers, depending on the adopted detection technique. This is a critical issue, in particular with a view to the necessity of providing suitable reference methods for monitoring biomass burners emissions. Second, we will show how it is possible to measure inside an artificial stack by using an optical multipass cell located across the gas flow, even at 140 °C, or in presence of soot.

定量检测工业排放中的污染物，特别是生物质燃烧器的排放，需要使用不同类型的分析仪。光学设备通常对废气的透明度和脏度敏感，因此光学测量通常是通过从烟囱中提取样品来进行的。本文具有双重目的。首先，我们将证明废气混合物的分子组成（特别是水和二氧化碳的浓度）会严重影响光学分析仪的结果，具体取决于所采用的检测技术。这是一个关键问题，特别是考虑到必须提供适当的参考方法来监测生物质燃烧器排放的问题。第二，