In the acidic water stripping tower, which one is removed first: H2S, CO2, or NH3?
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In a sewage air lift system, acidic water is fed into the air lift tower. Which of the gases – H2S, CO2, and NH3 – is removed first, and in what order? Why? Please explain, experts. Thank you; points will be given
Theoretically, it is carbon dioxide, followed by ammonia and hydrogen sulfide; ammonia and hydrogen sulfide react to form ammonium sulfide or ammonium hydrosulfide, and more heat is required for their decomposition
Could you explain why CO2 first, followed by ammonia and hydrogen sulfide?
At the same temperature, the medium with a lower solubility in water is vaporized first.
Acidic water contains a certain amount of CO2, which can also dissolve in water; however, its solubility is lower than that of H2S. At the same temperature, its vapor pressure is higher than that of H2S, so it evaporates more easily than NH3 and H2S
This post was last edited by Green Lotus on 2017-11-25 at 15:23. I’m sorry; I haven’t been online for a long time. Let me explain now: Acidic water is generally separated using a double-column stripping process. In the first column, hydrogen sulfide and carbon dioxide are separated from the vapor at the top of the column. Since hydrogen sulfide and carbon dioxide have a much higher relative volatility in water compared to ammonia, their concentrations in the vapor increase gradually during distillation, while the concentration of ammonia decreases. Eventually, ammonia remains trapped in the water. In the second column, ammonia is separated out
First carbon dioxide, then hydrogen sulfide, and finally ammonia