Do you have any questions regarding the treatment of ammonia nitrogen wastewater? ?
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There is ammonia-nitrogen wastewater with an ammonia-nitrogen concentration of 1000–1500 mg/L. After stripping using a stripping tower (under normal operating conditions), water is used to absorb the ammonia to form dilute ammonia water. My questions are: 1. What will be the concentration of this dilute ammonia water? 2. How to concentrate dilute ammonia water? 3. If acid is used for absorption, is sulfuric acid or hydrochloric acid better? 4. Can the resulting sulfuric acid an or ammonium chloride be concentrated by ammonia distillation after being adjusted with a base? Is steam used in ammonia evaporation? What conditions must be met for ammonia evaporation, and what concentration can the condensed ammonia nitrogen solution reach?
I’ve seen ammonia absorption processes in which sulfuric acid is used, as it is then sold as a fertilizer called diammonium sulfate; I’ve never heard of hydrochloric acid being used for this purpose. Water absorption could be tried, after all, ammonia is volatile. If the amount of ammonia present is low, equilibrium will surely be reached at a certain point, and no further absorption will occur. . . Can’t it be fed directly into the compression system? The critical point of liquid ammonia is quite high
If absorption by water is involved, the original poster can refer to the absorption chapter in Principles of Chemical Engineering. One balance line and one operating line are used to determine the minimum liquid-gas ratio; after that, a coefficient is applied to this ratio to obtain the actual liquid-gas ratio, and from this the amount of absorbent required can be determined. If acid is used for absorption, I support what was said on the 3rd floor – after all, it can be used as fertilizer. Moreover, both hydrochloric acid and ammonia are relatively volatile. So it’s better to use sulfuric acid for absorption. Regarding the issue of using the resulting sulfuric acid an or ammonium chloride and then adjusting with a base to increase concentration. I don’t think adding alkali makes any sense; the sulfuric acid AN solution after absorption already has an excess of acid. By adding alkali, sulfuric acid AN will decompose and release ammonia, meaning all the work done earlier would be in vain “I’ve had little exposure to the term “ammonia vaporization,” and I’ve never heard of it. If concentration is needed, it is recommended to try a multi-effect evaporator.
Using water for absorption doesn’t work; I’ve tried it before, and the pH of the water rises rapidly from 7 to over 9, after which absorption basically stops, with the concentration reaching over 70