Seeking wastewater ammonia treatment technologies
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Environmental regulations are becoming increasingly strict these days. The waste ammonia water in our factory is a real problem – is there any good technology available for dealing with it? Currently, the ammonia content in the wastewater coming from one of the towers is 500PPM. Is it possible to reduce this to below 100PPM? 50 is best. I would be grateful if all experts could share their insights. Thank you!
Through alkaline evaporation, it is theoretically possible to achieve an ammonia nitrogen level of 0 ppm in the water coming out of the atmospheric-pressure ammonia distillation tower; generally, a level of 10–30 ppm is not a problem； In a pressurized tower, it is entirely possible to achieve 0 ppm of ammonia nitrogen.
This post was last edited by zhaolijun on 2015-6-29 08:26. Blow-off tower? Order of influence factors on stripping efficiency: pH > gas-to-water ratio > residence time > temperature. Keep the pH around 11, and the MAP method can be used thereafter! I hope this helps you.
Ammonia can be recovered, and ammonia water can be sold for money
If it is only ammonia, it can be recovered through methods such as ammonia distillation and stripping to produce concentrated ammonia solution
Ammonia is vaporized in the tower, and then collected, cooled, and reused in the desulfurization system
This post was last edited by CoCo070563 on 2015-7-10 at 10:37. Our analysis suggests that the low efficiency of the ammonia evaporation towers is to blame; if needed, we have over 10 sets of such towers, which can keep the ammonia content in wastewater below 50 ppm. Contact me via in-site message, Wang Minghao.
There are two approaches: one is to improve existing equipment and processes. But it’s difficult to say, mainly due to the increased steam consumption. Second, further post-treatment is carried out on the treated wastewater. Given the ammonia concentration in the wastewater, it is somewhat difficult to meet the biochemical standards, unless the wastewater has a favorable carbon-to-nitrogen ratio and BOD value. For wastewater in this concentration range, it is economically unviable to remove ammonia using oxidation or adsorption methods. Distillation stripping is still left; it’s estimated that distillation will be used up first and then stripping, which manufacturers are not happy about. Gaseous membrane ammonia removal technology is suitable for this concentration range. Logically, this wastewater should still be alkaline (pH≥10.5); in that case, it can simply pass through a microporous hydrophobic membrane contactor, with an absorbent medium flowing on the other side of the membrane. The choice of absorbent medium depends on whether you need ammonia water or ammonium salts as the by-product. The energy consumption of this process is very low; to remove ammonia nitrogen from 500 ppm to 100 ppm in wastewater, approximately 0.7–0.9 kWh per ton of wastewater is required. Because the ammonia nitrogen removal rate is not high, and the investment is also low. The ammonia removal process using a gas-phase membrane has been industrialized. I have carried out a few such projects this year.
There are other components in the wastewater as well; it’s not difficult to reduce the ammonia level from 500 to 50 through simple denitrification