What is the principle of a smoke analyzer? The principle of smoke analyzer-Chemical Instrument Network

flue gas analyzerIt is a commonly used analytical instrument that uses electrochemical sensors to continuously analyze and measure the content of CO2, CO, NOx, SO2 and other flue gasesequipmentIt is mainly used for handheld environmental monitoring of pollution emissions from small fuel and gas boilers or near pollution sources. What is the principle of a smoke analyzer? Below, the editor will provide a specific introduction, hoping to help everyone.
flue gas analyzerThere are two commonly used working principles, one is the electrochemical working principle, and the other is the infrared working principle. At present, portable flue gas analyzers on the market usually combine these two principles. The following is an introduction to the working principles of these two flue gas analyzers:
Working principle of electrochemical gas sensor: After dust removal and dehumidification, the gas to be measured enters the sensor chamber, passes through the permeable membrane into the electrolytic cell, and the gas diffused and absorbed in the electrolyte undergoes potential electrolysis at a specified oxidation potential. The concentration of the gas is calculated based on the consumed electrolysis current.
Install the working electrode, counter electrode, and reference electrode in a cylindrical tank made of plastic, fill the electrolyte between the electrodes, and seal the top with a membrane made of porous tetrafluoroethylene. The connection between the preamplifier and the sensor electrode applies a certain potential between the electrodes to keep the sensor in working condition. The working electrode of gas in the electrolyte undergoes oxidation or reduction reactions, and when the electrode undergoes reduction or oxidation reactions, the equilibrium potential of the electrode changes, and the change value is proportional to the gas concentration. It can measure gases such as SO2, NO, NO2, CO, H2S, etc., but the sensitivity of these gas sensors varies. The order of sensitivity from high to low is H2S, NO, NO2, SO2, CO, and the response time is generally a few seconds to tens of seconds, usually less than 1 minute; Their lifespan ranges from as short as six months to as long as 2 or 3 years, while some CO sensors can last for several years.
infrared sensorWorking principle: Using the principle that different gases have special absorption characteristics for electromagnetic wave energy at infrared wavelengths to analyze gas composition and content.
Infrared radiation generally refers to electromagnetic radiation with wavelengths ranging from 0.76 μ m to 1000 μ m. The actual infrared wavelength used in infrared gas analysis instruments is approximately 1-50 μ m.