Treatment of high-concentration ammonia nitrogen wastewater
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The designed influent water quality for our company’s wastewater treatment plant is COD at 1000 mg/l and ammonia nitrogen at 500 mg/l. However, in actual operation, the ammonia nitrogen level in the influent water reaches 1500 mg/l, resulting in poor performance of the treatment plant; sludge bulking occurs, the activity of the sludge is low, and the ammonia nitrogen level in the effluent water exceeds 20 mg/l. I hope fellow sailors can help offer suggestions to solve this problem.
Suggestion: 1. If possible, the original wastewater should be diluted before being fed into the biochemical system; however, this will increase the water load on the system ； 2. What manufacturing process does the original poster use? Is it an A/O process? If it is necessary to increase the internal reflux rate without modifying the process system, that is, to raise the reflux ratio ； 3. If that still doesn’t work, the process will have to be modified; it is recommended to adopt an advanced A/O process.
An ammonia nitrogen level of 1500 is three times the designed value, which definitely indicates a problem in operation. I think the issue shouldn’t be sought in the water treatment process itself, but rather in the upstream stages – finding out what is causing the ammonia nitrogen level to be higher than the designed value. If it’s not possible to reduce the ammonia nitrogen level in the incoming water, pre-treatment should be added before the water enters the treatment system, so that the ammonia nitrogen level is brought down to the designed value before further treatment takes place. There are many methods for removing ammonia nitrogen, and you can choose one that suits your situation.
LZ’s operating system is really excellent – with an ammonia nitrogen concentration of 1500 in the inlet water, it drops to 200 in the outlet water, achieving a removal rate of 86%. When the ammonia nitrogen level exceeds 200, it becomes difficult to operate the aerobic biological treatment system; once it exceeds 400, microorganisms are suppressed or damaged. The reason why wastewater with high ammonia nitrogen levels is difficult to treat is that the pretreatment process is complicated – it’s as if a chemical plant has to be built. Whether using stripping, venting, or ammonia evaporation, an absorbent is required; otherwise, secondary air pollution will occur. LZ, you really need to think about how to implement proper pretreatment – that’s the only solution.
Control ammonia nitrogen in the incoming water by ensuring strict quality control at the source. It is recommended to add pretreatment to reduce ammonia nitrogen to the designed value before it enters the water treatment system.
By employing the low-temperature catalytic oxidation-desorption technique, ammonium salts in wastewater can be converted to free ammonia to the greatest extent possible under catalytic action; subsequent desorption at low air pressure enables the ammonia nitrogen content in the wastewater to meet **first-class discharge standards.
The system of the poster is working well – with an ammonia nitrogen level of 1500, the effluent can reach 20. What type of process is being used? Could you reveal it?
What is the source of the raw water? Is ammonia nitrogen organic or inorganic? The poster should provide an introduction to the water quality components to facilitate discussion among everyone–the administration should remind people about such issues.
That’s amazing – reducing such high levels of ammonia nitrogen to 20 is impossible for a biochemical system! ! ! If you want to ask about preprocessing, you need to know the water quality.
If the ammonia nitrogen level in the inlet water is 1500, can it be reduced to 20 in the outlet water? How is that possible? When the ammonia nitrogen concentration is high, the concentration of free ammonia becomes very high, and free ammonia has an inhibitory effect on microorganisms. Is there something wrong with the water quality analysis done by the owner? Moreover, few people would dare to adopt a design value of 500 for such a design.
May I ask the original poster, what is the source of your ammonia nitrogen? Is it synthetic ammonia? Urea?
It’s working well – the elevated ammonia nitrogen level can be reduced to 20; isn’t that already within the specified range?
If you still want to further reduce it, add another activated carbon filter
Our situation is similar to the original poster’s; I’m asking everyone the same question Also, what system is the original poster using? Can ammonia nitrogen levels of 1500 be reduced to the low tens?