The online monitoring of the coke oven flue gas emission chimney showed that sulfur dioxide levels were above the permissible limit; spraying ammonia water at a concentration of 10% directly into the chimney had no effect
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Online monitoring of the coke oven flue gas emission chimney showed excessive sulfur dioxide levels; spraying ammonia water at a 10% concentration directly into the chimney had no effect, and instead the sulfur dioxide levels rose rapidly. Later, it was changed to 20% ammonia solution, and the same thing happened; I don’t know why Is there anyone who understands chemistry? Visually, the ammonia solution appears to contain a higher proportion of yellow and green components; there may be an excess of trivalent iron. It’s not known whether sulfide compounds are present, as conducting tests is complicated due to the lack of a laboratory of one’s own. If sulfides are indeed present, they might react with oxygen to produce sulfur dioxide Does anyone understand this, or is there any way to avoid exceeding the limit?
Ammonia injection into flue gas is used to remove nitrogen oxides, not sulfur oxides.
Ammonia is sprayed in the denitration tower to remove nitrogen oxides; ammonia water is directly sprayed into the chimney for wet flue gas desulfurization. However, as the sulfur content increases, this becomes difficult to understand
Your testing device has phosphoric acid titration, right? Ammonia water is sprayed to form ammonium salts, which accumulate inside the testing tube; the more ammonia is sprayed, the higher the readings become
The first floor is correct; when the sulfur dioxide level is too high, spraying ammonia cannot reduce it. Sprinkling water can reduce the sulfur dioxide level slightly, but it is ineffective when the concentration is high. Check the desulfurization equipment; if it’s not available, it needs to be upgraded, otherwise it won’t pass the online detector tests.
The excessive sulfur impurities in ammonia water and the resulting effects； Furthermore, the production of ammonium salts from ammonia and sulfur oxides also decomposes at temperatures above 100 degrees Celsius; if the flue gas temperature is too high, it is difficult to achieve a high level of desulfurization ； Previously, ammonia was sprayed because the sulfur oxide analyzer in CEMS was affected by ammonia; however, modern CEMS systems have been improved.
Temperature relationship. Ammonium bisulfite, a salt of a weak acid and a weak base, finds it difficult to form a stable salt at the temperatures present in flue gas, and thus is not effective in removing sulfur dioxide.
Although the spraying of ammonia water leads to the formation of ammonium sulfite, ammonia water evaporates, resulting in high levels of ammonia gas. The wavelength range used for online detection of sulfur dioxide overlaps with that of ammonia gas; it is possible that ammonia gas interferes with the detection of sulfur dioxide