Ammonia-vaporized wastewater
Thread Content
I would like to ask fellow users: what causes the excessive ammonia nitrogen levels in ammonia-vaporized wastewater?
First, the amount of alkali added is insufficient to fully decompose the fixed ammonia in the ammonia solution; second, the temperature at the top of the ammonia distillation tower is low; third, the amount of alkali added is uneven
The process was not carried out strictly; there may be issues with the equipment, and the amount of alkali added was insufficient
By how much? How much steam is needed for one T of ammonia solution? What is the influent concentration?
Steam in the ammonia vaporization tower. The temperatures at the top and bottom of the tower are normal. When the alkali pump is functioning properly. That means the ammonia water heat exchanger is leaking!
Take a look at the structure of your ammonia vaporization towers. I was at a factory where the towers still used the oldest type of tray plates; as a result, even by using high pressure steam, it didn’t work properly. To ensure that the ammonia content in the wastewater is within acceptable levels, it’s necessary to modify the internal components of such towers. Replace it with the currently more advanced radial side-guided spray tray in China.
It might be due to insufficient alkaline addition, or uneven distribution of the alkaline substance. It is also possible that the temperature at the top of the tower is not high enough; both of these factors can result in insufficient distillation of the remaining ammonia water
1 gram of the fixed ammonium salt requires 2.3 to 2.5 grams of base; please calculate by yourself whether the amount of base added is sufficient. There is also a possibility of leakage from the excess ammonia water heat exchanger; in the case of a spiral plate heat exchanger, leakage at the inlet of the excess ammonia water can easily lead to it leaking into the wastewater. In the case of a tube heat exchanger, wastewater generally leaks into the residual ammonia solution. Generally, 200 kilograms of steam are required for 1 ton of residual ammonia water; of course, this depends on the structure of your tower, and I am referring here to a bubble column tower.
Ensure that the ammonia vaporization tower operates stably at a certain temperature and pressure; avoid frequent changes to the various parameters within the tower, as this can disrupt the equilibrium on the tray levels and reduce the efficiency of the tower. Furthermore, it is necessary to control the amount of alkali added in order to keep the pH value of the wastewater at the bottom of the tower between 8 and 9. Control the temperature of the ammonia solution entering the tower to ensure that the temperature at the bottom of the tower meets the specified standards. The steam pressure meets the requirements. Then there will be no problem