The purpose of adding alkali to the wastewater stripping tower
Thread Content
This post was last edited by adsl121 on 2010-4-24 09:43. What is the purpose of adding alkali to the wastewater stripping tower? What is the principle of chemical reactions? What is the impact of the location where alkali is added on the quality of the purified water?
This post was last edited by adsl121 on 2010-4-24 09:43. Organic amines cannot be decomposed during the stripping process; adding alkali can decompose organic amines, and without alkali, it is easy for the ammonia nitrogen level in the purified water to exceed the standard
This post was last edited by adsl121 on 2010-4-24 09:44. The increased content of fixed ammonia present in acidic water in the form of sulfuric acid and ammonium chloride (accounting for 30%-90% of the total ammonia content) affects the depth of ammonia stripping. When alkali is added to the stripping tower, the ammonia ions in the acidic water are subject to the following equilibria: (NH4)2SO4 + NaOH = NH4OH + Na2SO4 (1) and NH4OH = NH3 + H2O (2). When alkali is added to the stripping tower, the concentration of OH- increases, causing equilibrium (1) to shift to the right. As ammonia is continuously stripped away, equilibrium (2) also shifts to the right, thereby enabling the removal of fixed ammonia.
The last edit to this post was made by adsl121 on 2010-4-24 at 09:43. It depends on the equipment; in our case, ammonium salts account for 10%-20% of the total ammonia nitrogen. Relying solely on stripping, the concentration can only be reduced to 100-180 mg/l, and it’s difficult to lower it further. This must be achieved gradually, though the location where alkali is added varies depending on the capabilities of the equipment.
What exactly does it mean upstairs that “the location for adding alkali varies depending on the capacity of the device”? Could you explain? . .