How significant is the impact of CO when using the German Testo 350 flue gas analyzer to measure SO2?

This post was last edited by qqgd on 2024-7-11 08:53. For online flue gas analysis, non-dispersive infrared detection or laser tuning is generally used. Carbon monoxide has little impact on sulfur dioxide; however, the sampling system for catalytically regenerated flue gas and the methods used to process the samples have a significant influence on the measurement results. I don’t think there is any issue with the detection data from online analyzers, as NDIR analysis technology is mature and reliable. It is necessary to consider the properties of sulfur dioxide. In the flue gas from catalytic cracking regeneration, water is generated as a result of the combustion of hydrocarbons remaining on the catalyst during the regeneration process. At the same time, a certain proportion of oxidizing agents is added to the catalyst, so that carbon monoxide can be converted into carbon dioxide in the presence of residual oxygen during catalyst regeneration, thereby reducing the amount of residual carbon monoxide and recovering the heat released from its combustion. Sulfur dioxide present in the flue gas is also converted into sulfur trioxide in the presence of excess oxygen, and this reacts with water vapor to form sulfuric acid mist. As the gas passes through the sample treatment system, this acid mist is removed, and what the online flue gas analyzer actually measures is the residual sulfur dioxide. In fact, some of the nitrogen oxides in the flue gas come from this as well. The specific interaction between carbon monoxide and sulfur dioxide during analysis can only be determined by using your specific analytical instruments and methods to examine known simulated samples, as such interactions may be closely related to the analysis conditions and sample processing methods.