Given nitrogen oxides, how to calculate NO and NO2 in flue gas
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Given that the concentration of nitrogen oxides in the flue gas is 400 mg/m3, how can the concentration of nitric oxide and nitrogen dioxide in the flue gas be calculated? Seeking advice from experts
Why is there no one? Did I post in the wrong place?
It seems pretty complicated; I’m just throwing this out for everyone to discuss. 1. Some articles state that nitrogen oxides in flue gas consist of 90% NO and 10% NO2, with the rest being negligible. 2. Therefore, the concentration of NO in the flue gas is 360 mg/m3, and that of NO2 is 40 mg/m3. 3. The molecular weight of NO is 30, while that of NO2 is 46; hence, in the flue gas, there are 0.012 moles of NO and 0.00087 moles of NO2. 4. At standard atmospheric pressure, the volume of 1 mole of an ideal gas is 22.4 liters; of course, this value changes with temperature, and it should be possible to calculate it by making the necessary conversions.
What is used to determine the ratio of nitric oxide to nitrogen dioxide? The ratio given above is also based on certain conditions; it’s not clear how to determine this ratio given your specific operating conditions
Nitrogen oxides in flue gas are actually a mixture of nitric oxide and nitrogen dioxide. Under normal conditions, there is a conversion equilibrium between nitric oxide and nitrogen dioxide, with oxygen playing a role in this process; thus, the following kinetic equilibrium holds: NO + 1/2 O2 ↔ NO2. Generally, the oxygen content in flue gas is not very high, so nitric oxide predominates in this equilibrium. This equilibrium is affected by temperature – when the temperature is high, the equilibrium shifts to the left. The specific balance also depends on pressure. The original poster can consult the thermodynamic constants for nitrogen oxides to carry out approximate equilibrium calculations. At the same time, the influence of other coexisting components, as well as the effects of temperature and pressure, needs to be taken into account.
I feel that what the original poster is talking about is more academic in nature. What I actually want to ask is about the approximate range of nitrogen oxide levels in flue gas during engineering design; I’m not sure either about the actual temperature range of the flue gas
Thank you very much for your guidance. I happen to have another question: I need to design a fiberglass desulfurization tower. The inner diameter of this tower is supposed to be 7.5 meters, its height is 32 meters, the volume of flue gas flowing through it is 280,000 standard cubic meters, and the flue gas temperature is 50°C. Could you please advise me on how to calculate the thickness of this fiberglass tower?