Which is the main reaction in the ammonia combustion reaction?
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I read in the materials that there are three ways ammonia can decompose: 1. Reaction of ammonia with oxygen, 2. Decomposition reaction of ammonia, 3. Reaction of ammonia with SO2. Which reaction determines that ammonia combustion requires 1250 degrees? At what temperature conditions do all three reactions take place? Thank you!
All I know is that NH3 + O2 = N2 + H2O is the main reaction in sulfur production furnaces; this reaction must take place at temperatures above 1250°C, otherwise some of the ammonia will not burn or nitrogen oxides will be formed.
The main reaction in the ammonia burning process is the reaction between NH3 and SO2. Since the sulfur recovery unit involves an anaerobic reaction, oxygen first reacts with H2S to form SO2.
There are mainly 3 ammonia combustion reactions in sulfur recovery units: 1. 2NH3 + 3/2O2 = N2 + 3H2O. The rate of this reaction is **lower than that of the reaction between H2S and O2; in conditions of low oxygen availability, H2S consumes most of the oxygen in the reactor. At temperatures of around 1200°C and with sufficient oxygen, approximately 65% of the NH3 is decomposed. 2. 2NH3 = N2 + 3H2: In the absence of H2S and water, almost 100% of NH3 is decomposed at 1200°C; however, H2S and water strongly inhibit this reaction, resulting in a decomposition rate of less than 20% in most cases. 3. 2NH3 + SO2 = 2H2O + H2S + N2. This reaction occurs throughout the entire ammonia burning process, starting at 700°C, whereas the reaction between NH3 and O2 begins to take place only at 1200°C.
I strongly agree with the view from floor 5; indeed, ammonia reacts mainly with sulfur dioxide, and this is the main reaction that occurs during ammonia combustion.
I don’t have much knowledge about the desulfurization process; I’ve only learned about it through introductory materials. LZ can refer to the article in \"Petroleum and Natural Gas Chemistry\", issue 03 of 2008, which discusses the technical characteristics and existing problems of ammonia burning in sulfur recovery units
Ammonia and oxygen begin to react at 700 degrees; 4.9% decomposition occurs at 1000 degrees, while 90% decomposition is achieved at 1300 degrees. Due to the presence of hydrogen sulfide and water, only about 50% can be decomposed; the reaction between ammonia and SO2 is the main reaction. That is why the main reason for ammonia’s self-decomposition is 1250 degrees.
It’s the third one; it’s explained in detail in the book \"Sulfur Recovery Technology and Engineering\" written by Li Jingjing.
Sulfuric acid formed by the reaction of NH3 and SO2 can corrode and clog pipes
Under the conditions of the reactor, the reaction you are worried about will not occur.