A flue gas analyzer is an instrument used to measure the composition of pollutants in the flue gas generated by fuel combustion industrial boilers. It generally consists of various sensors such as infrared, chemiluminescence, and electrochemistry. The main measurement objects include oxygen (O2), carbon monoxide (CO), carbon dioxide (CO2), sulfur dioxide (SO2), nitrogen oxides (NOx), etc. The use of flue gas analyzer can analyze the combustion process of fuel, calculate the combustion efficiency of fuel, and achieve energy-saving production; Continuous monitoring and calculation of gaseous pollutants (SO2, NOx, etc.) and greenhouse gases (CO2, etc.) generated during combustion can also be carried out. Smoke analyzers can be divided into two types based on their usage: portable smoke analyzers and online continuous smoke monitoring analyzers. The so-called "online monitoring" refers to the continuous or timed monitoring of the condition of equipment without affecting its operation, usually automatically. Relatively speaking, offline monitoring is irregular and requires manual operation, usually using portable flue gas analyzers.