Why is the oxygen content in the furnace lower than that at the flue gas outlet? Zirconia is used for measuring the oxygen level in the furnace, while CEMS is used to measure the oxygen content at the flue gas outlet
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Why is the oxygen content in the furnace lower than that at the flue gas outlet? Zirconia is used for measuring the oxygen level in the furnace, while CEMS is used to measure the oxygen content at the flue gas outlet
With high flue gas temperatures, using zirconia eliminates the need for temperature reduction, saving money. Is CEMS required by the environmental protection agency in Shanghai? It involves using chromatography, and it’s also necessary to monitor temperature, pressure, and flow rate; it’s a very expensive setup
Zirconia can be used for flue ducts; it’s cheap and practical
The flue gas from furnace combustion needs to undergo denitration and desulfurization treatments, and dilution air is introduced, so the oxygen content at the outlet is higher than that in the furnace, where oxygen levels are low.
How are CEMS and zirconia compared together?
Is the furnace chamber under negative pressure? If so, there must be air leakage in the system； If denitration is involved, there must be dilution air ； So the oxygen content at the outlet will be higher than that in the furnace. The oxygen content measurement on CEMS should also be a zirconia sensor, right?
As mentioned by several fellow sailors above, since the smoke is monitored by CEMS only after desulfurization and denitrification, a certain amount of air is added as dilution air during operation, which results in a slight increase in oxygen content. Additionally, the zirconia method for measuring oxygen content inside the furnace has a relatively larger margin of error, as detection at high temperatures is affected by the sample temperature, furnace pressure, and the composition of the atmosphere within the furnace. For the samples measured by the CEMS system, the temperature drops, and the levels of certain sulfur oxides and nitrogen oxides also decrease. The measurement methods may be magnetooxidation or laser infrared, which result in better measurement stability.